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Mark Butala
You will implement a fourth-order, elliptical, low-pass infinite impulse-response (IIR) filter as a cascade of two second-order sections.
Cleuziou Christophe - - 2004
Inconsistencies about dynamic asymmetry between the on- and off-transient responses in VO2 are found in the literature. Therefore the purpose of this study was to examine VO2 on- and off-transients during moderate- and heavy-intensity cycling exercise in trained subjects. Ten men underwent an initial incremental test for the estimation of ...
Wysocki Marc - - 2004
OBJECTIVES: Proportional-assist ventilation (PAV) is able to unload respiratory muscles in proportion to the subject's inspiratory effort. However, leak-related alterations in the flow signal, effort-induced modifications in respiratory mechanics, or approximate adjustment of PAV could jeopardize such a theory. The aim of this study was to compare noninvasive PAV and ...
Romagnoli I - - 2004
The present study was designed to verify whether during hypercapnic stimulation, as we had previously found during exercise or walking, the partitioning of the respiratory motor output is equally distributed to the muscles of chest wall compartments to assist diaphragm function. We studied chest wall kinematics and respiratory muscle recruitment ...
Nof Eyal - - 2004
We evaluated a family with 30 members, 3 of whom had incessant polymorphous and bidirectional ventricular tachycardia (VT) that was electrocardiographically similar to that described in other familial polymorphic VT series; the VT was unrelated to exercise and asymptomatic. More subtle, but morphologically similar, ventricular arrhythmias were detected in 3 ...
Zafiropoulos Bill - - 2004
The aim of this study was to investigate the effects of mobilisation on respiratory and haemodynamic variables in the intubated, ventilated abdominal surgical patient. Mobilisation was defined as the progression of activity from supine, to sitting over the edge of the bed, standing, walking on the spot for one minute, ...
Ogata Hisayoshi - - 2004
This study was carried out to determine whether hemodynamics in inactive forearm muscle during ramp leg cycling is affected from the ventilatory threshold (VT) and respiratory compensation point (RCP), at which the rate of increase in ventilation (VE) against power output begins to increase abruptly. Change in hemodynamics was evaluated ...
van der Esch Martin - - 2004
Reduction of exercise capacity in patients with ankylosing spondylitis is associated with skeletal muscle performance. The contribution of respiratory muscle performance is questionable. This pilot study was designed to investigate the relationship between respiratory muscle performance and exercise capacity in ankylosing spondylitis. Subjects were 12 patients with ankylosing spondylitis. Measurements ...
van 't Hul A - - 2004
The aim of the present study was to evaluate the acute effects of inspiratory pressure support (IPS) of 5 cmH2O (IPS5) and 10 cmH2O (IPS10) on exercise endurance. Forty-five patients with COPD (mean forced expiratory volume in one second (FEV1) = 39 +/- 14% pred) performed three constant-load endurance tests ...
Hadjikoumi Irene - - 2003
The interrupter technique (Rint) is a noninvasive method for assessing respiratory resistance. The aims of this study were to assess whether upper airway support affects the measurement of Rint, if inspiratory or expiratory Rint were most reproducible, and which method of assessing Rint correlated best with spirometry results and was ...
Laplaud D - - 2003
AIM: The goal of this work was to highlight the effectiveness of a new submaximal exercise index of aerobic endurance using a single incremental test: the time at which oxygen uptake and carbon dioxide output are equal, i.e., when the respiratory exchange ratio (RER)=1.00. We studied 2 experimental sets, the ...
Cooper C E - - 2004
This study examines the ventilatory physiology of the numbat (Myrmecobius fasciatus), a small to medium-sized (550 g) termitivorous marsupial. Ventilatory parameters at thermoneutrality reflect the slightly low (83% of predicted) basal metabolic rate of the numbat, with ventilation frequency (fR; 30.6+/-3.65 breaths min(-1)), tidal volume [VT; 6.0+/-0.66 ml at body ...
Omiya Kazuto - - 2004
A double product break point (DPBP) occurs simultaneously with both ventilatory threshold (VT) and lactate threshold (LT) in normal subjects. We sought to determine whether a DPBP also occurs in cardiac patients and to investigate correlations between DPBP, VT and LT (study 1). We also evaluated a non-invasive DPBP measurement ...
Arena Ross - - 2003
BACKGROUND: The minute ventilation (VE)-carbon dioxide output (VCO(2)) relationship has recently been demonstrated to have prognostic significance in the heart failure (HF) population. However, the method by which the VE/VCO(2) slope is expressed has been inconsistent. METHODS: One hundred eighty-eight subjects, who had received diagnoses of HF, underwent exercise testing. ...
Larsen P D - - 2003
BACKGROUND: Cardioventilatory coupling is the triggering of inspiratory onset by preceding cardiac activity. We have observed two forms of coupling with a bimodal ('quantal') variation of respiratory period. METHODS: We investigated the variables of inspiratory duration (TI), expiratory duration (TE), and tidal volume (VT) where respiratory period variation was bimodal. ...
Cleuziou Christophe - - 2003
Inconsistencies about dynamic asymmetry between the on- and off-transient responses in .VO2 are found in the literature. Therefore the purpose of this study was to examine .VO2on- and off-transients during moderate- and heavy-intensity cycling exercise in trained subjects. Ten men underwent an initial incremental test for the estimation of ventilatory ...
Zhang Yi - - 2003
All respiratory long-term facilitation (LTF) is induced by inspiratory-excitatory stimulation, suggesting that LTF needs inspiratory augmentation and is the result of a Hebbian mechanism (coincident pre- and post-synaptic activity strengthens synapses). The present study examined the long-term effects of episodic inspiratory-inhibitory vagus nerve stimulation (VNS) on phrenic nerve activity. We ...
Kaygisiz Ziya - - 2003
The purpose of the study was to investigate the effects of one night's sleep deprivation on the cardiorespiratory responses to exercise during the follicular and luteal phases of the menstrual cycle. We have studied nine, healthy females aged 24-35 years with regular menstrual cycles. Each subject performed spirometric tests at ...
Eikermann Matthias - - 2003
BACKGROUND: Residual paralysis increases the risk of pulmonary complications but is difficult to detect. To test the hypothesis that accelerometry predicts effects of residual paralysis on pulmonary and upper airway function, the authors related tests of pulmonary and pharyngeal function to accelerometry of adductor pollicis muscle in 12 partially paralyzed ...
Gigliotti Francesco - - 2003
BACKGROUND: To our knowledge, no data have been reported on the effects of exercise training (EXT) on central respiratory motor output or neuromuscular coupling (NMC) of the ventilatory pump, and their potential association with exertional dyspnea. Accurate assessment of these important clinical outcomes is integral to effective management of breathlessness ...
Witte K K A - - 2003
To determine the pattern of the abnormal ventilatory response in heart failure and how it relates to symptoms by looking at tidal volume (VT) and frequency (f) during exercise. 45 patients with heart failure and 21 controls underwent maximal treadmill based exercise testing with metabolic gas exchange analysis. The relation ...
Connolly Declan Aj DA Human Performance Laboratory, Room 212, Patrick Gymnasium University of Vermont Burlington , - - 2003
ATP repletion following exhaustive exercise is approximated to be 90-95% complete in 3 minutes, and is crucial in the performance of short duration, high intensity work. Few studies appear to have used this 3-minute interval in the investigation of recovery modes, blood lactate accumulation and power output. Thus, our aim ...
Shibuya Ken-ichi - - 2003
It has been hypothesized that the signals of near infrared spectroscopy (NIRS) would reflect muscle O(2) uptake (mVO(2)). Although it is not definite that NIRS signals accurately reflect mVO(2), there is every possibility that NIRS signals at least reflect regional O(2) uptake (rVO(2)). The phase II kinetics of pulmonary oxygen ...
Lucia Alejandro - - 2003
PURPOSE: To compare the total exercise loads (intensity x volume) of the Vuelta a España and Tour de France during the last year. METHODS: Seven professional road cyclists (28 +/- 1 yr; [OV0312]O(2max): 74.6 +/- 2.2 mL.kg-1.min-1) who participated in both Tour and Vuelta during the years 1997, 1999, 2000, ...
Ikarugi Hideo - - 2003
Platelets play a crucial role in the pathogenesis of acute cardiac events, such as angina, myocardial infarction and sudden death. It is believed that regular low-intensity exercise can reduce, while high-intensity exercise may provoke acute cardiac events. The aim of the present study was to investigate the effect of acute ...
Neder J A - - 2003
Clinical evaluation of the pattern and timing of breathing during submaximal exercise can be valuable for the identification of the mechanical ventilatory consequences of different disease processes and for assessing the efficacy of certain interventions. Sedentary individuals (60 male/60 female, aged 20-80 yrs) were randomly selected from >8,000 subjects and ...
Grassi Bruno - - 2003
Near-infrared spectroscopy (NIRS) was utilized to gain insights into the kinetics of oxidative metabolism during exercise transitions. Ten untrained young men were tested on a cycle ergometer during transitions from unloaded pedaling to 5 min of constant-load exercise below (<VT) or above (>VT) the ventilatory threshold. Vastus lateralis oxygenation was ...
Mahon Anthony D - - 2003
This study examined ratings of perceived exertion (RPE) using Borg's 6-20 scale at 50 W, 80 W, and ventilatory threshold (VT) in 10-year-old children (n = 15) during two different graded exercise tests. Power output was increased by 10 W.min(-1) in one protocol and by 30 W.3 min(-1) in the ...
Lucia A - - 2003
The exercise volume and intensity are reported of a male professional cyclist (age 30; VO2max 75.0 ml/kg/min) who successfully completed the 2001 Giro d'Italia (May), Tour de France (July), and Vuelta a España (September). The total exercise time during the Giro, Tour, and Vuelta was 90 hours 44 minutes (5444 ...
Dixit Sanjay - - 2002
Mapping strategies for ventricular tachycardia (VT) have evolved significantly in the past 2 decades. This review discusses mapping techniques that can help in successful VT ablation. The electrocardiogram (ECG) remains a vital component of VT mapping and can help to identify the chamber of origin of VT. The ECG morphology ...
Qin Chao - - 2002
The aim of this study was to determine if thoracic respiratory interneurons (TRINs) might receive peripheral noxious somatic and visceral inputs. Extracellular potentials of 78 respiration-related T(3) neurons, whose activity was driven by central respiratory output, were recorded from the intermediate zone in pentobarbital anesthetized, paralyzed, and ventilated male rats. ...
Babb T G - - 2002
The purpose of this study was to determine the effect of imposed external resistance on the ventilatory response to He-O(2) breathing during peak exercise. To accomplish this purpose, separate inspiratory and expiratory external resistances were applied to offset for the decrease in intrapulmonary airway resistance with He-O(2) breathing. Seven men ...
Paton Julian F R - - 2002
This article reviews recent studies on the importance of glycine receptors for both the spontaneous and the reflex respiratory modulation of the laryngeal abductors and adductors. Our findings show that strychnine blockade of glycine receptors within the brainstem changes the eupneic three-phase respiratory pattern into two phases. This has major ...
Huang Chien Hui - - 2003
This study investigated the effect of inspiratory muscle strength training (IMST) on inspiratory motor drive [mouth occlusion pressure at 0.1 s (P(0.1))] and respiratory-related evoked potentials (RREP). It was hypothesized that, if IMST increased inspiratory muscle strength, inspiratory motor drive would decrease. If motor drive were related to the RREP, ...
Martinez José Antônio Baddini - - 2002
CONTEXT: Dyspnea remains a therapeutic challenge, especially in chronic respiratory conditions. Recent studies have shown that the induction of unpleasant dyspnea sensations activates areas in the insular cortex. OBJECTIVE: This study was designed to investigate the potential effects of ondansetron, a potent anti-serotonin agent, on induced dyspnea sensation. TYPE OF ...
Franklin S H - - 2002
Dorsal displacement of the soft palate (DDSP) is one of the most common obstructive conditions of the upper respiratory tract in the racehorse. The present study was conducted to determine the effects of intermittent dorsal displacement of the soft palate (DDSP) on ventilation and respiratory airflow during high intensity exercise. ...
McCool F Dennis - - 2002
STUDY OBJECTIVES: To determine the accuracy of a portable magnetometer designed to measure tidal volume (VT), inspiratory time (TI), and expiratory time (TE). PARTICIPANTS: Fourteen healthy subjects. DESIGN: Subjects breathed over a sixfold range of VTs while at rest (sitting and standing) and during treadmill exercise. We then compared VT, ...
Bogun Frank - - 2002
BACKGROUND: Critical sites within reentry circuits of postinfarction ventricular tachycardia (VT) were identified during sinus rhythm (SR) and VT to determine whether electrogram characteristics during SR may be helpful in identifying successful ablation sites. METHODS: In 33 patients (mean age 67 +/- 11 yrs) with prior infarction, mapping and radiofrequency ...
Mutolo Donatella - - 2002
The role played by the Bötzinger complex (BötC), the pre-Bötzinger complex (pre-BötC), and the more rostral extent of the inspiratory portion of the ventral respiratory group (iVRG) in the genesis of the eupneic pattern of breathing was investigated in anesthetized, vagotomized, paralyzed, and artificially ventilated rabbits by means of kainic ...
Boersma Lucas - - 2002
BACKGROUND: The role of dispersion of refractoriness and reentry for the genesis of polymorphic ventricular tachycardia (VT) has recently become emphasized. We investigated the mechanisms of polymorphic arrhythmias in a 2D preparation confining an area of prolonged refractoriness. METHODS AND RESULTS: In 16 Langendorff-perfused rabbit hearts, a sheet of left ...
Hart Nicholas - - 2002
Patients with isolated diaphragm paralysis depend on recruitment of extradiaphragmatic respiratory muscles to increase ventilation, but little is known about exercise performance or the response of the inspiratory muscles to loaded breathing. By convention, unilateral diaphragm paralysis is regarded as a trivial condition whereas bilateral paralysis is considered to be ...
de Durante Gabriella - - 2002
The ARDSNet trial revealed that the use of a smaller tidal volume (VT) reduced mortality by 22%. However, three earlier studies that lowered VT did not find a decrease in mortality. We tested the hypothesis that the increased respiratory rate used in the ARDSNet lower VT strategy might have led ...
Swissa Moshe - - 2002
We tested the hypothesis that sildenafil, singly or in combination with nitric oxide (NO) donors, promotes ventricular tachycardia (VT) and ventricular fibrillation (VF). Vulnerability to VT/VF was tested by rapid pacing in eight isolated normal swine right ventricles (RV). The endocardial activation was optically mapped, and the dynamic action potential ...
Iandelli Iacopo - - 2002
To understand how externally applied expiratory flow limitation (EFL) leads to impaired exercise performance and dyspnea, we studied six healthy males during control incremental exercise to exhaustion (C) and with EFL at approximately 1. We measured volume at the mouth (Vm), esophageal, gastric and transdiaphragmatic (Pdi) pressures, maximal exercise power ...
Aliverti Andrea - - 2002
To determine how decreasing velocity of shortening (U) of expiratory muscles affects breathing during exercise, six normal men performed incremental exercise with externally imposed expiratory flow limitation (EFLe) at approximately 1 l/s. We measured volumes of chest wall, lung- and diaphragm-apposed rib cage (Vrc,p and Vrc,a, respectively), and abdomen (Vab) ...
Dolmage Thomas E - - 2002
STUDY OBJECTIVE: Estimating lung volume using inspiratory capacity (IC) maneuvers is a useful way of tracking dynamic hyperinflation. An understanding of the repeatability of the IC in a clinical setting is important when evaluating an individual's response to a therapeutic intervention that might influence lung volume. This is the first ...
Bogun Frank - - 2002
INTRODUCTION: Multiple forms of ventricular tachycardia (VT) after myocardial infarction may result from multiple reentrant circuits that share an isthmus or from separate reentrant circuits. The prevalence of a shared isthmus in patients with multiple hemodynamically tolerated VTs has not been determined. METHODS AND RESULTS: Criteria for a shared isthmus ...
Maury Philippe - - 2002
Although the value of T wave alternans as an index of electrical instability has been extensively investigated, little is known about QRS alternans during VT. Intracardiac electrograms of 111 episodes of spontaneous monomorphic regular VT retrieved from implantable defibrillators in 25 patients were retrospectively selected. Three beat series, representing the ...
Grönkvist Mikael - - 2002
The influences of body posture and tidal volume (VT) on inter- and intraregional ventilation inhomogeneity were assessed by normalized phase III slope (Sn(III)) analysis of multiple-breath washout recordings of SF(6) and He in 11 healthy men. Washouts with target VT of 750, 1,000, and 1,250 ml were performed standing and ...
Bettinelli D - - 2002
Chest wall mechanics was studied in four subjects on changing gravity in the craniocaudal direction (G(z)) during parabolic flights. The thorax appears very compliant at 0 G(z): its recoil changes only from -2 to 2 cmH(2)O in the volume range of 30-70% vital capacity (VC). Increasing G(z) from 0 to ...
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