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  • 1
    Electronic Resource
    Electronic Resource
    Tetrachlorosilane Consumption in Radio Frequency Glow Discharge (1998)
    Springer
    Plasma chemistry and plasma processing 18 (1998), S. 509-533 
    Details
    ISSN: 1572-8986
    Keywords: RF SiCl4 discharge ; mass spectrometry ; kinetics ; decomposition ; oxidation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Technology
    Notes: Abstract Time-resolved mass spectrometry was used for analysis of the plasma reactions in radio frequency (RF) SiCl 4 and SiCl 4 −O 2 discharges as functions of starting partial pressure and electrical power. Molecular concentrations of the reactants and products from SiCl 4 alone and with O 2 were obtained from the mass spectra and used for plotting the kinetic curves. The SiCl 4 and O 2 consumption rates were calculated from the kinetic curves and compared with results of theoretical simulation of the reaction. Direct electron impact decomposition was found to be the main pathway for pure SiCl 4 conversion. On the contrary, the consumption of SiCl 4 in the SiCl 4 +O 2 mixtures was largely chemical. The experimental macrokinetics are in agreement with a model in which oxidation is caused by the atomic oxygen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1021811316740
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  • 2
    Electronic Resource
    Electronic Resource
    Oxidation of Styrene in a Silent Discharge Plasma (1999)
    Springer
    Plasma chemistry and plasma processing 19 (1999), S. 131-151 
    Details
    ISSN: 1572-8986
    Keywords: Styrene ; oxidation ; silent discharge ; plasma ; dielectric barrier
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Technology
    Notes: Abstract A silent discharge plasma reactor has been developed to study the oxidation of styrene vapor in argon/oxygen mixtures. A number of analytical techniques were employed to determine the destruction efficiency and to characterize the intermediate products. The destruction efficiency was measured as a function of initial styrene concentration, temperature, and energy density of the plasma. The formation of solid products was observed in most experiments. At low temperature (100°C), the solid deposit was polymeric in nature, while at high temperature (300°C) the solid appeared to be amorphous carbon. A combination of high temperature and high energy density resulted in high destruction efficiency and minimal production of solid films. The destruction efficiency vs. energy density is shown to be more complex than a simple model predicting exponential behavior. Several reasons for the discrepancy are suggested. The “e-folding” energy density for the destruction of styrene is compared to literature values for other organic compounds, measured using similar types of plasma reactors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1021812201545
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  • 3
    Electronic Resource
    Electronic Resource
    Oxidation of Dilute Benzene in an Alumina Hybrid Plasma Reactor at Atmospheric Pressure (1999)
    Springer
    Plasma chemistry and plasma processing 19 (1999), S. 383-394 
    Details
    ISSN: 1572-8986
    Keywords: Nonthermal plasma ; benzene ; Al2O3 ; BaTiO3 ; oxidation ; absorption ; atmospheric pressure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Technology
    Notes: Abstract The combination of plasma discharge and adsorption was examined for oxidation of dilute benzene in air in a plasma reactor packed with a mixture of BaTiO 3 pellets and porous Al 2 O 3 pellets (i.e., an alumina hybrid reactor). The oxidative decomposition of benzene was enhanced by the benzene concentrating on the Al 2 O 3 pellets. Furthermore, there was a higher selectivity to CO 2 in the products from the hybrid than from a plasma reactor packed with BaTiO 3 pellets alone. The presence of the Al 2 O 3 pellets suppressed the formation of N 2 O.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1021820403362
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  • 4
    Electronic Resource
    Electronic Resource
    Oxidation and Reduction Processes During NO x Removal with Corona-Induced Nonthermal Plasma (1999)
    Springer
    Plasma chemistry and plasma processing 19 (1999), S. 421-443 
    Details
    ISSN: 1572-8986
    Keywords: Streamer corona ; NO x removal ; nonthermal plasma ; oxidation ; reduction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Technology
    Notes: Abstract In this paper, the NO-to-NO 2 conversion in various gaseous mixtures is experimentally investigated. Streamer coronas are produced with a dc-superimposed high-frequency ac power supply (10–60 kHz). According to NO x removal experiments in N 2 +NO x and N 2 +O 2 +NO x gaseous mixtures, it is supposed that the reverse reaction NO 2 +O→NO+O 2 may not only limit NO 2 production in N 2 +NO x mixtures, but also increase the energy cost for NO removal. Oxygen could significantly suppress reduction reactions and enhance oxidation processes. The reduction reactions, such as N+NO→N 2 +O, induce negligible NO removal provided the O 2 concentration is larger than 3.6%. With adding H 2 O into the reactor, the produced NO 2 per unit removed NO can be significantly reduced due to NO 2 oxidation. NH 3 injection could also significantly decrease the produced NO 2 via NH and NH 2 - related reduction reactions. Almost 100% of NO 2 can be removed in gaseous mixtures of N 2 +O 2 +H 2 O+NO 2 with negligible NO production.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1021824504271
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  • 5
    Electronic Resource
    Electronic Resource
    Universal Correlation of Nitrogen 1s and Oxygen 1s Photoelectron Binding Energies with Chemical Composition in Nitrogen-Containing Plasma Polymers (1999)
    Springer
    Plasmas and polymers 4 (1999), S. 283-307 
    Details
    ISSN: 1572-8978
    Keywords: Plasma polymers ; oxidation ; XPS ; photoelectron binding energy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Technology
    Notes: Abstract The incorporation of oxygen into nitrogen-containing plasma deposited polymers was studied by X-ray Photoelectron Spectroscopy (XPS). As the oxygen content of the plasma polymer increased, the binding energy of the N 1s photoelectrons increased. Conversely, the binding energy of the O 1s photoelectrons was inversely proportional to the nitrogen content of the plasma polymer. The data from a large number of samples all obeyed the same “universal” correlations of photoelectron binding energy versus chemical composition. The data were described by the same curve regardless of whether the oxygen was incorporated rapidly into the thin film during plasma deposition or whether the oxygen was added slowly during spontaneous oxidation of the film in air. This implies that the same thermodynamic principles of radical reactions governed the addition of oxygen to the plasma polymer. The shift in the O 1s and N 1s photoelectron binding energies as a function of chemical composition was used to monitor the proximity of nitrogen and oxygen. By contrasting the experimental data with a simple binomial model which described the random addition of oxygen to a lattice containing carbon and nitrogen, we were able to show that oxygen was preferentially added near nitrogen-containing groups in plasma polymers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1021831527895
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  • 6
    Electronic Resource
    Electronic Resource
    Looking around: 35 years of oculomotor modeling (1995)
    Springer
    Annals of biomedical engineering 23 (1995), S. 456-466 
    Details
    ISSN: 1573-9686
    Keywords: Eye movement ; Oculomotor ; Model ; Space
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Eye movements have attracted an unusually large number of researchers from many disparate fields, especially over the past 35 years. The lure of this system stemmed from its apparent simplicity of description, measurement, and analysis, as well as the promise of providing a “window in the mind.” Investigators in areas ranging from biological control systems and neurological diagnosis to applications in advertising and flight simulation expected eye movements to provide clear indicators of what the sensory-motor system was accomplishing and what the brain found to be of interest. The parallels between compensatory eye movements and perception of spatial orientation have been a subject for active study in visual-vestibular interaction, where substantial knowledge has accumulated through experiments largely guided by the challenge of proving or disproving model predictions. Even though oculomotor control has arguably benefited more from systems theory than any other branch of motor control, many of the original goals remain largely unfulfilled. This paper considers some of the promising potential benefits of eye movement research and compares accomplishments with anticipated results. Four topics are considered in greater detail: (i) the definition of oculomotor system input and output, (ii) optimization of the eye movement system, (iii) the relationship between compensatory eye movements and spatial orientation through the “internal model,” and (iv) the significance of eye movements as measured in (outer) space.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00000012
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  • 7
    Electronic Resource
    Electronic Resource
    1997 Whitaker Distinguished Lecture: Models to Solve Mysteries in Biomechanics at the Cellular Level; A New View of Fiber Matrix Layers (1998)
    Springer
    Annals of biomedical engineering 26 (1998), S. 627-643 
    Details
    ISSN: 1573-9686
    Keywords: Starling's hypothesis ; Surface glycocalyx ; Lacunar–canalicular porosity ; Fluid flow in bone ; Fluid shear hypothesis in bone ; Intimal transport ; Leaky-junction–cell-turnover hypothesis ; Whitaker ; Model ; Cell biomechanics ; Fiber matrix
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Three different fundamental cellular level transport models are presented to explore current or recently solved mysteries in what appear to be three unrelated problem areas: (i) Starling's hypothesis for lymph formation in the microcirculation; (ii) the cellular level transduction and transmission mechanisms for sensing and communicating mechanical strain in bone; and (iii) the growth of cellular level macromolecular leakage spots in the arterial intima and their relation to the formation of subendothelial liposomes. This trilogy of what appear to be unrelated problems is shown to have a common link, the thin layer of specialized matrix that cells produce at the surface of their plasmalemma membranes in part to regulate the water and solute transport that surrounds them. In each case unexpected model predictions have led to new hypotheses and the design of new experiments which have helped explain long-standing fundamental questions in biomechanics. © 1998 Biomedical Engineering Society. PAC98: 0130Bb, 8710+e, 8745-k, 8722-q
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1114/1.134
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  • 8
    Electronic Resource
    Electronic Resource
    A Mathematical Model of Gas Exchange in an Intravenous Membrane Oxygenator (1998)
    Springer
    Annals of biomedical engineering 26 (1998), S. 166-178 
    Details
    ISSN: 1573-9686
    Keywords: ARDS ; Intravenous oxygenation ; Artificial lung ; Mathematical model ; Model ; Gas exchange ; Oxygenator
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Acute respiratory distress syndrome (ARDS) is a pulmonary edemic condition which reduces respiratory exchange in 150,000 people per year in the United States. The currently available therapies of mechanical ventilation and extracorporeal membrane oxygenation are associated with high mortality rates, so intravenous oxygenation represents an attractive, alternative support modality. We are developing an intravenous membrane oxygenator (IMO) device intended to provide 50% of basal oxygen and carbon dioxide exchange requirements for ARDS patients. A unique aspect of the IMO is its use of an integral balloon to provide active mixing. This paper describes a mathematical model which was developed to quantify and optimize the gas exchange performance of the IMO. The model focuses on balloon activated mixing, uses a lumped compartment approach, and approximates the blood-side mass transfer coefficients with cross-flow correlations. IMO gas exchange was simulated in water and blood, for a variety of device geometries and balloon pulsation rates. The modeling predicts the following: (1) gas exchange efficiency is reduced by a buildup of oxygen in the fluid near the fibers; (2) the IMO gas exchange rate in blood is normally about twice that in water under comparable conditions; (3) a balloon diameter of about 1.5 cm leads to optimal gas exchange performance; and (4) in vivo positioning can affect gas exchange rates. The numerically predicted gas transfer rates correlate closely with those experimentally measured in vitro for current IMO prototypes. © 1998 Biomedical Engineering Society. PAC98: 8710+e, 8790+y, 8265Fr
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1114/1.53
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  • 9
    Electronic Resource
    Electronic Resource
    Mechanism of Ca++ Release from the Sarcoplasmic Reticulum: A Computer Model (1998)
    Springer
    Annals of biomedical engineering 26 (1998), S. 213-229 
    Details
    ISSN: 1573-9686
    Keywords: Ca++ myocyte cycling ; Ca++ channels ; Ca++ transient ; Mechanical restitution ; Ca++ release ; Sarcoplasmic reticulum ; Model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract The proposed model describes myocyte calcium (Ca++) cycling, emphasizing the kinetics of sarcoplasmic reticulum (SR) Ca++ release channels. The suggested SR channel regulating mechanism includes two types of Ca++ binding sites: (1) low affinity sites with high binding rates, regulating the opening of Ca++ channels and (2) high affinity sites with low binding rates, which regulate their closing. The amount of Ca++ released from the SR and the peak value of Ca++ ion concentration [Ca++] in the cytoplasm were found to depend on the rate of the increase of [Ca++], similar to Ca++ induced Ca++ release experiments. The model describes spontaneous release of Ca++ from overloaded SR. The dependence of the control mechanism on the activating and inactivating sites is substantiated by simulations of ryanodine intervention, providing results similar to experimental results. Simulations under conditions of isolated SR vesicles produced Ca++ release results similar to measured data. Consequently, it is suggested that the recovery of Ca++ release channels represents the rate limiting factor in the process of mechanical restitution. © 1998 Biomedical Engineering Society. PAC98: 8722Fy, 8710+e
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1114/1.54
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  • 10
    Electronic Resource
    Electronic Resource
    Particle Motion Within In Vitro Models of Stenosed Internal Carotid and Left Anterior Descending Coronary Arteries (1998)
    Springer
    Annals of biomedical engineering 26 (1998), S. 190-199 
    Details
    ISSN: 1573-9686
    Keywords: Particle residence time ; In vitro model ; Artery: carotid ; Artery: coronary ; Stenosis ; Particle motion ; Model ; Artery: stenosed
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Asymmetric 75% and 95% area reduction, transparent Sylgard stenotic models were operated under internal carotid artery (ICA) (Womersley parameter, α=5.36, Remean=213 and 180, respectively, and Repeak=734 and 410, respectively) and left anterior descending coronary artery (LAD) flow wave forms (α=2.65,Remean=59 and 57, respectively, and Repeak=137 and 94, respectively) to evaluate the effect of these conditions on particle residence times downstream of the stenoses. Amberlite particles (1.05 g/cm3, 400 μm) were added to the fluid to simulate platelets and their motion through the stenotic region and were traced using a laser light sheet flow visualization method with pseudo-color display. Two-dimensional (2D) particle motions were recorded and particle washout in the stenotic throat and downstream section were computed for all cases. All four model cases demonstrated jetting through the stenosis which followed an arching pattern around a large separation zone downstream. Considerable mixing was observed within these vortex regions during high flow phases. Particle washout profiles showed no clear trend between the degrees of stenosis although particles downstream of the stenoses tended to remain longer for LAD conditions. The critical washout cycle (1% of particles remaining downstream of the stenosis), however, was longer for the 95% stenoses cases under each flow condition due to the larger protected region immediately downstream and maximal for the LAD 95% case. Results of this study suggest that particle residence times downstream of 75% and 95% stenoses (~ 3–6 s for ICA and ~ 8–10 s for LAD) exceed the minimum time for platelet adhesion (~ 1 s) for at least 1% of cells and, thus, may be sufficient to initiate thrombus formation under resting conditions. © 1998 Biomedical Engineering Society. PAC98: 8745Hw, 8722-q, 4727Wg, 4732Cc
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1114/1.131
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  • 11
    Electronic Resource
    Electronic Resource
    Iterative Fast Orthogonal Search for Modeling by a Sum of Exponentials or Sinusoids (1998)
    Springer
    Annals of biomedical engineering 26 (1998), S. 315-327 
    Details
    ISSN: 1573-9686
    Keywords: Time-constant estimation ; Exponential series modeling ; Spectral analysis ; Nonlinear least squares ; Fast orthogonal search ; Model ; Exponentials ; Sinusoids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Accurate sinusoidal series models of biological time-series data may be obtained using a modeling algorithm known as fast orthogonal search (FOS). FOS does not require equally spaced data, and can resolve sinusoidal frequencies much more closely spaced than can a discrete Fourier transform. FOS has been less successful at obtaining accurate exponential series models. We here consider a modification of FOS in which iteration of the original procedure is used to further reduce the mean-squared error (m.s.e.) between model and data, approaching a minimum in the m.s.e. Iteration of the FOS procedure greatly improves the accuracy of estimated exponential series models. The application of iterative FOS (IFOS) to exponential and sinusoidal series models is described. Finally, the use of FOS and IFOS procedures for finding a single model from the results of multiple experiments is described. © 1998 Biomedical Engineering Society. PAC98: 8710+e, 0270Hm
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1114/1.90
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  • 12
    Electronic Resource
    Electronic Resource
    In Vivo Kinematics of the Rabbit Knee in Unstable Models of Osteoarthrosis (1998)
    Springer
    Annals of biomedical engineering 26 (1998), S. 353-360 
    Details
    ISSN: 1573-9686
    Keywords: Knee ; Kinematics ; In vivo ; Osteoarthrosis ; Rabbit ; Model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract The effects of osteoarthrosis inducing surgery on the kinematics of the rabbit knee were evaluated in vivo. A video motion analysis system was used to track reflective markers attached to two pins fixed in both femur and tibia, and from these data knee kinematics were computed. The control for all measurements was the gait after pins were implanted, but the knee was unaltered. Both a release of the anterior cruciate ligament and a partial medial meniscectomy were then performed, and the animals' gait was recorded at 4, 8 and 12 weeks after knee surgery. Knee kinematics were described by three translations and three rotations and were analyzed in terms of maximum and minimum values and range of motion. Statistical comparisons of these data between control and operated knees were made using Wilcoxon's signed rank test. Results showed an initial increase in maximum anterior displacement which returned to normal after 12 weeks. In addition there was a persistent increase in knee adduction and an increase in the minimum value of external rotation over the 12 week period. At 12 weeks after surgery there was no change in range of any measurable kinematic parameter. Overall, the changes in joint kinematics following partial medial meniscectomy and release of the anterior cruciate ligament were small, suggesting that altered joint kinematics might not be a critical factor in the development of osteoarthrosis in this animal model.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1114/1.133
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  • 13
    Electronic Resource
    Electronic Resource
    An Engineering Model of Dynamic Cardiomyoplasty. I. (1998)
    Springer
    Annals of biomedical engineering 26 (1998), S. 441-453 
    Details
    ISSN: 1573-9686
    Keywords: Elastance ; Stroke volume ; Model ; Cardiomyoplasty
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Dynamic cardiomyoplasty (DCM) is an emerging surgical procedure for heart failure in which the patient's latissimus dorsi (LD) muscle is wrapped around the heart and stimulated to contract in synchrony with the heartbeat as a cardiac assist measure. A 6 week training protocol of progressive electrical stimulation renders the normally fatigueable skeletal muscle fatigue-resistant and suitable for chronic stimulation. To date, over 500 procedures have been performed in worldwide clinical trials. Investigators typically report symptomatic improvement and modest hemodynamic improvement in patients. Controversy exists regarding the exact mechanism of DCM. To test the hypothesis that DCM augments cardiac stroke volume through improvement in systolic function, we formulated an engineering model of dynamic cardiomyoplasty to predict stroke volume. The heart and the LD were modeled as nested (series) elastance chambers, and the vasculature was represented by a two-element Windkessel model. Using five healthy goats, we verified model predictions of stroke volume for both stimulator ON beats (y=1.00x−0.08, r=0.87, p 〈 0.0001) and OFF beats (y=1.01x+1.06, r=0.91, p 〈 0.0001), where x and y are the measured and predicted stroke volumes, respectively. The model confirms that using untrained latissimus dorsi applied to the normal myocardium produces only moderate increases in stroke volume and suggests that future research should focus on increasing LD strength after training.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1114/1.77
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  • 14
    Electronic Resource
    Electronic Resource
    Regional Myocardial Perfusion and Mechanics: A Model-Based Method of Analysis (1998)
    Springer
    Annals of biomedical engineering 26 (1998), S. 743-755 
    Details
    ISSN: 1573-9686
    Keywords: Strain ; Fiber ; Blood flow ; Flow-function relation ; Acute myocardial ischemia ; Functional border zone ; Heart ; Left ventricle ; Microspheres ; Myocardial perfusion ; Mechanics ; Model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract A new parametric model-based method has been developed that allows epicardial strain distributions to be computed on the left ventricular free wall in normal and ischemic myocardium and integrated with the regional distributions of anatomic and physiological measurements so that underlying relationships can be explored. An array of radiopaque markers was sewn on the anterior wall of the left ventricle (LV) in three anesthetized open-chest canines, and their positions were recorded using biplane video fluoroscopy before and 2 min after occlusion of the left anterior descending coronary artery. The three-dimensional (3D) anatomy of the LV and epicardial fiber angles were measured post-mortem using a 3D probe. A prolate spheroidal finite element model was fitted to the epicardial surface points (with 〈0.2 mm accuracy) and fiber angles (〈5° error). Regional myocardial blood flows (MBFs) were measured using fluorescent microspheres and fitted into the model(〈0.3 ml min−1 g−1 error). Epicardial fiber and cross-fiber strain distributions were computed by allowing the model to deform from end-diastole to end-systole according to the recorded motion of the surface markers. Systolic fiber strain varied from −0.05 to 0.01 within the region of the markers during baseline, and regional MBF varied from 1.5 to 2.0 min−1 g−1. During 2 min ischemia, regional MBF was less than 0.3 min−1 g−1 in the ischemic region and 1.0 ml min−1 g−1 in the nonischemic region, and fiber strain ranged from 0.05 in the central ischemic zone to −0.025 in the remote nonischemic tissue. This analysis revealed a zone of impaired fiber shortening extending into the normally perfused myocardium that was significantly wider at the base than the apex. A validation analysis showed that a regularizing function can be optimized to minimize both fitting errors and numerical oscillations in the computed strain fields. © 1998 Biomedical Engineering Society. PAC98: 8745Hw, 8710+e, 8759Wc, 8745-k
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1114/1.74
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  • 15
    Electronic Resource
    Electronic Resource
    An Engineering Model of Dynamic Cardiomyoplasty. II. Clinical Applications (1998)
    Springer
    Annals of biomedical engineering 26 (1998), S. 454-461 
    Details
    ISSN: 1573-9686
    Keywords: Clinical cardiomyoplasty ; Nomogram ; Muscle transformation ; Model ; Cardiomyoplasty ; Applications
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Previously, a modification to the Sunagawa engineering model for the isolated left ventricle and arterial system was proposed and validated for dynamic cardiomyoplasty in an acute goat preparation. To test the hypothesis that this model may be applied to the clinical scenario in cardiomyoplasty patients, we predicted human stroke volume using the model with human clinical data from the literature. Predicted stroke volume correlated well with published stroke volume in patients who have had the dynamic cardiomyoplasty procedure. These results suggest that the modest hemodynamic improvement commonly reported after the procedure is performed may be due to diminished latissimus dorsi strength after transformation. The validity of both the original Sunagawa model and the previously proposed modification for dynamic cardiomyoplasty is further supported with these results. A nomogram methodology for predicting stroke volume after dynamic cardiomyoplasty for any particular patient is presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1114/1.37
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