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Sample records for sharp phase myocardial

  1. Is there a sharp phase transition for deterministic cellular automata?

    Wootters, W.K.

    1990-01-01

    Previous work has suggested that there is a kind of phase transition between deterministic automata exhibiting periodic behavior and those exhibiting chaotic behavior. However, unlike the usual phase transitions of physics, this transition takes place over a range of values of the parameter rather than at a specific value. The present paper asks whether the transition can be made sharp, either by taking the limit of an infinitely large rule table, or by changing the parameter in terms of which the space of automata is explored. We find strong evidence that, for the class of automata we consider, the transition does become sharp in the limit of an infinite number of symbols, the size of the neighborhood being held fixed. Our work also suggests an alternative parameter in terms of which it is likely that the transition will become fairly sharp even if one does not increase the number of symbols. In the course of our analysis, we find that mean field theory, which is our main tool, gives surprisingly good predictions of the statistical properties of the class of automata we consider. 18 refs., 6 figs

  2. A sharp interface method for compressible liquid–vapor flow with phase transition and surface tension

    Fechter, Stefan, E-mail: stefan.fechter@iag.uni-stuttgart.de [Institut für Aerodynamik und Gasdynamik, Universität Stuttgart, Pfaffenwaldring 21, 70569 Stuttgart (Germany); Munz, Claus-Dieter, E-mail: munz@iag.uni-stuttgart.de [Institut für Aerodynamik und Gasdynamik, Universität Stuttgart, Pfaffenwaldring 21, 70569 Stuttgart (Germany); Rohde, Christian, E-mail: Christian.Rohde@mathematik.uni-stuttgart.de [Institut für Angewandte Analysis und Numerische Simulation, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart (Germany); Zeiler, Christoph, E-mail: Christoph.Zeiler@mathematik.uni-stuttgart.de [Institut für Angewandte Analysis und Numerische Simulation, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart (Germany)

    2017-05-01

    The numerical approximation of non-isothermal liquid–vapor flow within the compressible regime is a difficult task because complex physical effects at the phase interfaces can govern the global flow behavior. We present a sharp interface approach which treats the interface as a shock-wave like discontinuity. Any mixing of fluid phases is avoided by using the flow solver in the bulk regions only, and a ghost-fluid approach close to the interface. The coupling states for the numerical solution in the bulk regions are determined by the solution of local two-phase Riemann problems across the interface. The Riemann solution accounts for the relevant physics by enforcing appropriate jump conditions at the phase boundary. A wide variety of interface effects can be handled in a thermodynamically consistent way. This includes surface tension or mass/energy transfer by phase transition. Moreover, the local normal speed of the interface, which is needed to calculate the time evolution of the interface, is given by the Riemann solution. The interface tracking itself is based on a level-set method. The focus in this paper is the description of the two-phase Riemann solver and its usage within the sharp interface approach. One-dimensional problems are selected to validate the approach. Finally, the three-dimensional simulation of a wobbling droplet and a shock droplet interaction in two dimensions are shown. In both problems phase transition and surface tension determine the global bulk behavior.

  3. Sharps injury reduction: a six-year, three-phase study comparing use of a small patient-room sharps disposal container with a larger engineered container.

    Grimmond, T; Naisoro, W

    2014-09-01

    A 350-bed Sydney hospital noted excessive container-associated sharps injuries (CASI) using small sharps containers and compared the effect from 2004 to 2010 of using a larger container engineered to reduce CASI. In Phase 1 (Ph1), disposable 1.4L containers (BD Australia) were carried to/from patients' rooms. In Phase 2 (Ph2), this stopped and a safety-engineered 32L reusable container (the Device; Sharpsmart, SteriHealth) was mounted in medication stations only and sharps were carried to and from patient rooms using kidney dishes. In Phase 3 (Ph3), the Device was wall-mounted in patient rooms. Sharps injuries were categorised as 'during-procedure', 'after-procedure but before disposal', 'CASI', and 'improper disposal SI'. Disposal-related SI comprised CASI plus improper-disposal SI. Injuries per 100 full-time-equivalent staff were analysed using Chi 2 ; p ≤ 0.05; and relative risk and 95% confidence limits were calculated. In Ph1 (small containers) 19.4% of SI were CASI and transport injuries were zero. In Ph2 (Device in medication station) CASI fell 94.9% ( p <0.001); Disposal-related SI fell 71.1% ( p =0.002) but transport injuries rose significantly. In Ph3 (Device in patient room) zero CASI occurred ( p <0.001); Disposal-related SI fell 83.1% ( p =0.001). Recapping SI fell 85.1% ( p =0.01) with the Device. The Device's volume, large aperture, passive overfill-protection and close-at-hand siting are postulated as SI reduction factors.

  4. Finite element approximation of a sharp interface approach for gradient flow dynamics of two-phase biomembranes

    Barrett, John W.; Garcke, Harald; Nürnberg, Robert

    2017-01-01

    A finite element method for the evolution of a two-phase membrane in a sharp interface formulation is introduced. The evolution equations are given as an $L^2$--gradient flow of an energy involving an elastic bending energy and a line energy. In the two phases Helfrich-type evolution equations are prescribed, and on the interface, an evolving curve on an evolving surface, highly nonlinear boundary conditions have to hold. Here we consider both $C^0$-- and $C^1$--matching conditions for the su...

  5. Effects of Phytoplankton Growth Phase on Delayed Settling Behavior of Marine Snow Aggregates at Sharp Density Transitions

    Proctor, K. W.; Montgomery, Q. W.; Prairie, J. C.

    2016-02-01

    Marine snow aggregates play a fundamental role in the marine carbon cycle. Since marine snow aggregates are larger and thus sink faster than individual phytoplankton, aggregates often dominate carbon flux. Previous studies have shown that marine snow aggregates will significantly decrease their settling velocity when passing through sharp density transitions within the ocean, a phenomenon defined as delayed settling. Given the importance of aggregate settling to carbon export, these small-scale changes in aggregate settling dynamics may have significant impacts on the efficiency of the biological pump. However, there is still a lack of knowledge about how different physical properties of aggregates can affect this delayed settling. In this study, we investigated the effect of phytoplankton growth phase on delayed settling behavior. Using phytoplankton cultures stopped at four different growth phases, we formed marine snow aggregates in the laboratory in rotating cylindrical tanks. We then observed individual aggregates as they settled through a stratified tank. We will present data which illustrates that aggregates experience greatly reduced settling rates when passing through sharp density gradients and that the growth phase of the phytoplankton used to form these aggregates has a significant effect on this delayed settling behavior. A thorough understanding of the impact of phytoplankton growth phase on the delayed settling behavior of marine snow will offer insight into the way phytoplankton growth phase may influence the efficiency of the biological pump, carbon flux, and the carbon cycle as a whole.

  6. Influence of phase transformations on the asymptotic residual stress distribution arising near a sharp V-notch tip

    Ferro, P

    2012-01-01

    In this work, the residual stress distribution induced by the solidification and cooling of a fusion zone in the vicinity of a sharp V-notch tip is investigated. The intensity of the residual asymptotic stress fields, quantified by the notch stress intensity factors, was studied for two different V-notch specimen geometries under generalized plane-strain conditions. In order to analyze the influence of phase transformations on the obtained results, simulations with and without the effects of phase transformation were carried out on ASTM SA 516 steel plates. Thanks to the possibilities of numerical modelling, additional analyses were performed without taking into account the transformation plasticity phenomenon. It was found that phase transformation effects (both volume change and transformation plasticity) have a great influence on the intensity and sign of the asymptotic stress fields at the sharp V-notch tips. This result is believed to be very important for the correct numerical determination (and future applications) of notch stress intensity factors resulting from asymptotic residual stress distributions induced by transient thermal loads. The analyses were performed with the finite element code SYSWELD. (paper)

  7. Relationship between myocardial flow reserve by oxygen-15 water positron emission tomography in the subacute phase of myocardial infarction and left ventricular remodeling in the chronic phase

    Ohara, Minako; Yukiiri, Kazushi; Masugata, Hisashi

    2008-01-01

    The purposes of this study were to examine the effects of angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB) on myocardial flow reserve in patients with acute myocardial infarction (AMI) in the subacute phase using oxygen-15 positron emission tomography (PET) and to elucidate the relationship between the myocardial flow reserve and remodeling in the chronic phase. Sixty patients who had been treated with coronary angioplasty within 12 h after the onset of AMI were enrolled. Patients were divided into an enalapril (ACEI) group and a candesartan (ARB) group. The myocardial flow reserve was measured by oxygen-15 water PET in the subacute phase from the 20th to the 30th day after the onset of AMI. Left ventriculography was performed to measure the left ventricular ejection fraction in the chronic phase about 6 months after the onset. Ten patients (33%) in the enalapril group and 4 patients (13%) in the candesartan group stopped taking their respective medications within a few days of starting, because of side effects such as cough or hypotension. Thus, the prevalence of medication intolerance was higher in the enalapril group. The myocardial flow reserve in the subacute phase and the left ventricular ejection fraction in the chronic phase were lower in the enalapril group (2.08±0.30 and 42±6%) than in the candesartan group (2.25±0.20 and 49±5%) (p<0.05). The myocardial flow reserve significantly correlated with the left ventricular ejection fraction in all patients (r=0.45, p<0.01). The myocardial flow reserve assessed by PET in the subacute phase after AMI was found to be related to left ventricular remodeling in the chronic phase. (author)

  8. Value of the Doppler index of myocardial performance in the early phase of acute myocardial infarction

    Poulsen, S H; Jensen, S E; Tei, C

    2000-01-01

    Prospective assessment of a nongeometric Doppler-derived index of combined systolic and diastolic myocardial performance was performed in 64 patients with acute myocardial infarction (MI) within 1 hour after their arrival to the hospital and in 39 age-matched healthy subjects. The index is defined...

  9. Profile of MIBI liquid phase radiopharmaceutical for myocardial imaging

    I Daruwati; ME Sriyani; NK Oekar; N Zainuddin; KA Hanafiah

    2016-01-01

    The 99m Tc-MIBI radiopharmaceutical has been used in nuclear medicine in Indonesia for myocardial imaging. BATAN researchers have mastered the technology to manufacture MIBI as a lyophilized kit. A reformulation of MIBI radiopharmaceutical has been conducted to improve the stability of the kit especially in the liquid-phase kit. Basically, radiopharmaceuticals in liquid form are not different from the dry kit. However in the manufacturing of liquid-phase kit, lyophilization process was not done. To improve the stability of liquid kit, a reformulation of the components was conducted by using two separate vials (Formulation 2) and the characteristics were compared with the one-vial formulation (Formulation 1). The MIBI Formulation 2 consists of two vials, vial A containing 0.06 mg of SnCl 2 2H 2 O and 2.6 mg Sodium Citrate 2H 2 O and vial B containing 0.5 mg of [Cu(MIBI) 4 ]BF 4 , 1 mg of cysteine hydrochloride, and 20 mg of mannitol. The purposes of this study were to determine the stability of two different formulations of MIBI as a liquid-phase kit, to compare their stability in different storage condition such as in refrigerator and freezer, and to compare the ratio of activities attained between target and nontarget organs after injection to animal model. As a diagnostic agent, MIBI was reconstituted with Technetium-99m as radionuclide tracer to 99m Tc-MIBI labeled compound. The radiochemical purity of 99m Tc-MIBI was determined by chromatography method using alumina thin-layer chromatography paper as the stationary phase and ethanol 95% as the mobile phase. The results showed MIBI Formulation 2 has a higher stability than Formulation 1. Formulation 2 also maintained a 96.68% radiochemical purity under 52-day storage and attained a target-to-nontarget activity ratio of 8.22. (author)

  10. Sharps container

    Lee, Angelene M. (Inventor)

    1992-01-01

    This invention relates to a system for use in disposing of potentially hazardous items and more particularly a Sharps receptacle for used hypodermic needles and the like. A Sharps container is constructed from lightweight alodined nonmagnetic metal material with a cup member having an elongated tapered shape and length greater than its transverse dimensions. A magnet in the cup member provides for metal retention in the container. A nonmagnetic lid member has an opening and spring biased closure flap member. The flap member is constructed from stainless steel. A Velcro patch on the container permits selective attachment at desired locations.

  11. Domain patterns and hysteresis in phase-transforming solids: analysis and numerical simulations of a sharp interface dissipative model via phase-field approximation

    DeSimone, A.; Kružík, Martin

    2013-01-01

    Roč. 8, č. 2 (2013), s. 481-499 ISSN 1556-1801 R&D Projects: GA ČR(CZ) GAP201/12/0671 Institutional support: RVO:67985556 Keywords : hysteresis * shape memory Subject RIV: BA - General Mathematics Impact factor: 0.952, year: 2013 http://library.utia.cas.cz/separaty/2013/MTR/kruzik-domain patterns and hysteresis in phase-transforming solids analysis and numerical simulations of a sharp interface dissipative model via phase-field approximation.pdf

  12. Phase analysis of gated blood pool scintigraphy in traumatic myocardial contusion

    Nishimaki, Hiroshi; Kobayashi, Akiyoshi

    1994-01-01

    It is not easy to make a diagnosis of myocardial contusion following blunt chest trauma, because most patients have many other concurrent injuries with diverse symptoms. The usefulness of phase analysis of gated blood pool scintigraphy (GBPS) for myocardial contusion following blunt chest trauma was evaluated. Thirty-eight patients who had been strongly suspected of having myocardial contusion from clinical symptoms and electrocardiograms underwent phase analysis of GBPS. The results of phase analysis were compared with those of two-dimensional echocardiography (2-D Echo) and CPK-MB fraction measurement in all patients, with those of 201 TlCl myocardial scintigraphy in 35 patients and with those of 99m Tc-pyrophosphate scintigraphy in 10 patients. In 29 patients (76.3%), the results of phase analysis matched those of 2-D Echo. Two patients (5.3%) who were judged as positive by 2-D Echo and as negative by phase analysis had only rupture of the chordae. Only one of two other patients who were judged as negative by 2-D Echo and as positive by phase analysis was judged as positive by 201 TlCl myocardial scintigraphy. The results of both 2-D Echo and phase analysis were not well correlated with those of CPK-MB fraction measurement and 99m Tc pyrophosphate scintigraphy. It is concluded that phase analysis of GBPS, as well as 2-D Echo, is useful for diagnosing myocardial contusion, and that phase analysis is most useful for diagnosing myocardial contusion in patients who cannot be examined by 2-D Echo because of the presence of pneumothorax and/or subcutaneous emphysema in the anterior chest wall. (author)

  13. Phase analysis of gated blood pool scintigraphy in traumatic myocardial contusion

    Nishimaki, Hiroshi; Kobayashi, Akiyoshi (Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Medicine)

    1994-01-01

    It is not easy to make a diagnosis of myocardial contusion following blunt chest trauma, because most patients have many other concurrent injuries with diverse symptoms. The usefulness of phase analysis of gated blood pool scintigraphy (GBPS) for myocardial contusion following blunt chest trauma was evaluated. Thirty-eight patients who had been strongly suspected of having myocardial contusion from clinical symptoms and electrocardiograms underwent phase analysis of GBPS. The results of phase analysis were compared with those of two-dimensional echocardiography (2-D Echo) and CPK-MB fraction measurement in all patients, with those of [sup 201]TlCl myocardial scintigraphy in 35 patients and with those of [sup 99m]Tc-pyrophosphate scintigraphy in 10 patients. In 29 patients (76.3%), the results of phase analysis matched those of 2-D Echo. Two patients (5.3%) who were judged as positive by 2-D Echo and as negative by phase analysis had only rupture of the chordae. Only one of two other patients who were judged as negative by 2-D Echo and as positive by phase analysis was judged as positive by [sup 201]TlCl myocardial scintigraphy. The results of both 2-D Echo and phase analysis were not well correlated with those of CPK-MB fraction measurement and [sup 99m]Tc pyrophosphate scintigraphy. It is concluded that phase analysis of GBPS, as well as 2-D Echo, is useful for diagnosing myocardial contusion, and that phase analysis is most useful for diagnosing myocardial contusion in patients who cannot be examined by 2-D Echo because of the presence of pneumothorax and/or subcutaneous emphysema in the anterior chest wall. (author).

  14. Seismic observation of a sharp post-garnet phase transition within the Farallon crust: Evidence for oceanic plateau subduction

    Maguire, R.; Ritsema, J.

    2017-12-01

    The tectonic evolution of North America over the past 150 million years was heavily influenced by the complex subduction history of the Farallon plate. In particular, Laramide mountain building may have been triggered by the initiation of flat slab subduction in the late Cretaceous. While it has been proposed that the cause of slab flattening is related to the subduction of an oceanic plateau[1], direct geophysical evidence of a subducted oceanic plateau is lacking. Here, using P-to-S receiver functions, we detect a sharp seismic discontinuity at 720-km depth beneath the southeastern United States and Gulf of Mexico. We interpret this discontinuity as a garnet-to-bridgmanite phase transition occurring within a thickened Farallon crust. Our results are consistent with a subducted oceanic plateau (likely the conjugate half of the Hess rise) which is foundering below the base of the mantle transition zone. Additionally, we find a strong 520-km discontinuity beneath the southeastern United States which may indicate a hydrous transition zone due to the release of H2O from the Farallon slab. These results provide insight into the dynamics of flat slab subduction as well as the tectonic history of North America. [1] Livaccari, R. F., Burke, K., & Şengör, A. M. C. (1981). Was the Laramide orogeny related to subduction of an oceanic plateau? Nature, v. 289, p. 276-278, doi: 10.1038/289276a0

  15. Myocardial enhancement pattern in patients with acute myocardial infarction on two-phase contrast-enhanced Ecg-gated multidetector-row computed tomography

    Ko, S.M.; Seo, J.B.; Hong, M.K.; Do, K.H.; Lee, S.H.; Lee, J.S.; Song, J.W.; Park, S.J.; Park, S.W.; Lim, T.H.

    2006-01-01

    Aim: To evaluate the myocardial enhancement pattern of the left ventricle on two-phase contrast-enhanced electrocardiogram (ECG)-gated multidetector computed tomography (MDCT) images in patients with acute myocardial infarction (AMI). METHODS: Two-phase contrast-enhanced ECG-gated MDCT examinations were performed in 16 patients with AMI. The presence, location and pattern of myocardial enhancement were evaluated. MDCT findings were compared with the catheter angiographic results. RESULTS: Subendocardial (n=9) or transmural (n=6) area of early perfusion defects of the myocardium was detected in 15 of 16 patients (94%) on early-phase CT images. Variable delayed myocardial enhancement patterns on late-phase CT images were observed in 12 patients (75%): (1) subendocardial residual perfusion defect and subepicardial late enhancement (n=6); (2) transmural late enhancement (n=1); (3) isolated subendocardial late enhancement (n=1); and (4) isolated subendocardial residual perfusion defect (n=2). On catheter angiography, 14 of 15 corresponding coronary arteries showed significant stenosis. CONCLUSION: Variable abnormal myocardial enhancement pattern was seen on two-phase, contrast-enhanced ECG-gated MDCT in patients with AMI. Assessment of myocardial attenuation on CT angiography gives additional information of the location and extent of infarction

  16. Changes in the phase and amplitude images in the rehabilitation phase after myocardial infarction

    Csernay, L.; Mester, J.; Vidakovich, T.; Rajtar, M.; Pavics, L.; Szasz, K.

    1984-01-01

    A studing involving patients with completed myocardial infarction, who underwent a 3-week exercise program at a cardiocirculatory rehabilitation center in Southern Hungary, is described. Infarctions were confirmed by the typical clinical and ECG signs and symptoms as well as by 201-T1 imaging at rest. Patients with normal 201-T1 activity distribution were excluded. Three ECG-gated equilibrium radionuclide studies were performed in each case: The first was done on the first day of rehabilitation (at a mean post-infarction interval of 1.5 months); the second study was scheduled 3 weeks after the first on completion of the exercise program and the last 9 weeks after the first (on an outpatient basis). From April 25, 1983 to September 9, 1983 a total of 25 patients were investigated. Of these, 9 had normal 201-T1 images. Of the remaining 16, 9 showed no significant changes of the phase and amplitude images. In 2 cases dyskinesia was found to have been replaced by akinesia, and in another 3 akinesia was replaced by hypokinesia. By contrast, 2 previously akinetic patients became dyskinetic. We expect to increase our patient material to at least 50 cases by the end of 1983 and would like to present our results, illustrating them by some typical examples. (Author)

  17. Improved detection of chronic myocardial infarction with Fourier amplitude and phase imaging in two projections

    Akins, E.W.; Scott, E.A.; Williams, C.M.

    1987-01-01

    Twenty-seven patients with 33 chronic myocaridal infarctions underwent MR imaging and radionuclide ventriculography at rest. The radionuclide ventriculographs, in left anterior oblique (LAO) and left posterior oblique (LPO) projections, were analyzed by two independent observers by visual inspection and combined Fourier-transformed amplitude and phase imaging. Only 15 (45%) of the 33 infarctions were detected by visual inspection, but 21 (64%) were detected on the LAO Fourier-transformed images along. Thirty (91%) were detected by using both LAO and LPO Fourier-transformed images. On MR imaging, 28 (85%) of the myocardial infarctions appeared as areas of focal wall thinning. Combined Fourier-transformed amplitude and phase imaging in both LAO and LPO views discloses more myocardial infarctions than visual inspection or LAO Fourier-transformed images alone because inferior infarctions, which are frequently missed in the LAO view, are easily seen in the LPO view

  18. The association between reconstructed phase space and Artificial Neural Networks for vectorcardiographic recognition of myocardial infarction.

    Costa, Cecília M; Silva, Ittalo S; de Sousa, Rafael D; Hortegal, Renato A; Regis, Carlos Danilo M

    Myocardial infarction is one of the leading causes of death worldwide. As it is life threatening, it requires an immediate and precise treatment. Due to this, a growing number of research and innovations in the field of biomedical signal processing is in high demand. This paper proposes the association of Reconstructed Phase Space and Artificial Neural Networks for Vectorcardiography Myocardial Infarction Recognition. The algorithm promotes better results for the box size 10 × 10 and the combination of four parameters: box counting (Vx), box counting (Vz), self-similarity method (Vx) and self-similarity method (Vy) with sensitivity = 92%, specificity = 96% and accuracy = 94%. The topographic diagnosis presented different performances for different types of infarctions with better results for anterior wall infarctions and less accurate results for inferior infarctions. Copyright © 2018 Elsevier Inc. All rights reserved.

  19. Mutual information and phase dependencies: measures of reduced nonlinear cardiorespiratory interactions after myocardial infarction.

    Hoyer, Dirk; Leder, Uwe; Hoyer, Heike; Pompe, Bernd; Sommer, Michael; Zwiener, Ulrich

    2002-01-01

    The heart rate variability (HRV) is related to several mechanisms of the complex autonomic functioning such as respiratory heart rate modulation and phase dependencies between heart beat cycles and breathing cycles. The underlying processes are basically nonlinear. In order to understand and quantitatively assess those physiological interactions an adequate coupling analysis is necessary. We hypothesized that nonlinear measures of HRV and cardiorespiratory interdependencies are superior to the standard HRV measures in classifying patients after acute myocardial infarction. We introduced mutual information measures which provide access to nonlinear interdependencies as counterpart to the classically linear correlation analysis. The nonlinear statistical autodependencies of HRV were quantified by auto mutual information, the respiratory heart rate modulation by cardiorespiratory cross mutual information, respectively. The phase interdependencies between heart beat cycles and breathing cycles were assessed basing on the histograms of the frequency ratios of the instantaneous heart beat and respiratory cycles. Furthermore, the relative duration of phase synchronized intervals was acquired. We investigated 39 patients after acute myocardial infarction versus 24 controls. The discrimination of these groups was improved by cardiorespiratory cross mutual information measures and phase interdependencies measures in comparison to the linear standard HRV measures. This result was statistically confirmed by means of logistic regression models of particular variable subsets and their receiver operating characteristics.

  20. Late-phase MSCT in the different stages of myocardial infarction: animal experiments

    Mahnken, Andreas H.; Bruners, Philipp; Kinzel, Sylvia; Katoh, Marcus; Muehlenbruch, Georg; Guenther, Rolf W.; Wildberger, Joachim E.

    2007-01-01

    The purpose of this study was to intraindividually evaluate myocardial late enhancement on multislice spiral computed tomography (MSCT) for the assessment of the different stages of myocardial infarction (MI) in comparison with magnetic resonance (MR) imaging. Reperfused MI was successfully induced in seven pigs. Delayed enhancement MR imaging and late-phase MSCT were performed on day 0 as well as 7, 28 and 90 days after the procedure. The pigs were sacrificed, and 2,3,5-triphenyltetrazolin-chloride (TTC) staining was acquired. MI size was compared between the different imaging techniques and over time applying Bland-Altman plots and multivariate analysis with repeated measures. On day 0 the mean MI size was 23.7 ± 11.8% of the left ventricular area on MSCT and 24.5 ± 10.6% on MR imaging. On day 90 infarct sizes decreased significantly to 16.9 ± 8.4% and 18.9 ± 8.0%, respectively (P 0.0019). On TTC staining the size of MI was 16.8 ± 8.2%. Bland-Altman plots showed a good agreement between MSCT and MR imaging with mean deviations ranging from -3.4% to -1.9%. No significant difference between MSCT and MR imaging was found. Myocardial late enhancement on MSCT correlates well with delayed enhancement MR imaging during the different stages of MI and allows for reliable assessment of reperfused MI during acute, subacute and chronic stages. (orig.)

  1. A volume-preserving sharpening approach for the propagation of sharp phase boundaries in multiphase lattice Boltzmann simulations

    Reis, T.; Dellar, P.J.

    2011-01-01

    Lattice Boltzmann models that recover a macroscopic description of multiphase flow of immiscible liquids typically represent the boundaries between phases using a scalar function, the phase field, that varies smoothly over several grid points. Attempts to tune the model parameters to minimise the widths of these interfaces typically lead to the interfaces becoming fixed to the underlying grid instead of advecting with the fluid velocity. This phenomenon, known as lattice pinning, is strikingly similar to that associated with the numerical simulation of conservation laws coupled to stiff algebraic source terms. We present a lattice Boltzmann formulation of the model problem proposed by LeVeque and Yee (1990) [3] to study the latter phenomenon in the context of computational combustion, and offer a volume-conserving extension in multiple space dimensions. Inspired by the random projection method of Bao and Jin (2000) [1] we further generalise this formulation by introducing a uniformly distributed quasi-random variable into the term responsible for the sharpening of phase boundaries. This method is mass conserving, gives correct average propagation speeds over many timesteps, and is shown to significantly delay the onset of pinning as the interface width is reduced. © 2010 Elsevier Ltd.

  2. A volume-preserving sharpening approach for the propagation of sharp phase boundaries in multiphase lattice Boltzmann simulations

    Reis, T.

    2011-07-01

    Lattice Boltzmann models that recover a macroscopic description of multiphase flow of immiscible liquids typically represent the boundaries between phases using a scalar function, the phase field, that varies smoothly over several grid points. Attempts to tune the model parameters to minimise the widths of these interfaces typically lead to the interfaces becoming fixed to the underlying grid instead of advecting with the fluid velocity. This phenomenon, known as lattice pinning, is strikingly similar to that associated with the numerical simulation of conservation laws coupled to stiff algebraic source terms. We present a lattice Boltzmann formulation of the model problem proposed by LeVeque and Yee (1990) [3] to study the latter phenomenon in the context of computational combustion, and offer a volume-conserving extension in multiple space dimensions. Inspired by the random projection method of Bao and Jin (2000) [1] we further generalise this formulation by introducing a uniformly distributed quasi-random variable into the term responsible for the sharpening of phase boundaries. This method is mass conserving, gives correct average propagation speeds over many timesteps, and is shown to significantly delay the onset of pinning as the interface width is reduced. © 2010 Elsevier Ltd.

  3. Nuclear medicine methods in the field of studying the mechanisms of delayed phase of myocardial preconditioning

    Wang Shuxia

    2001-01-01

    Ischemic preconditioning is the intrinsic and most potently myocardial protection. Its mechanism is the foundation of rational therapeutic application. Nowadays there are some theories about delayed phase of preconditioning such as nitric oxide hypothesis, free radical mechanisms, protective protein synthesis and opening of ATP-sensitive potassium channels. By incorporation 3 H-leucine, using liquid scintillation counter, the authors know there was protective protein synthesis during preconditioning. SPECT could study the characteristics of preconditioned myocardium in vivo, and PET might further show the metabolism, energy consumption and its relationship to myocardium dysfunction

  4. Sharpening Sharpe Ratios

    William N. Goetzmann; Jonathan E. Ingersoll Jr.; Matthew I. Spiegel; Ivo Welch

    2002-01-01

    It is now well known that the Sharpe ratio and other related reward-to-risk measures may be manipulated with option-like strategies. In this paper we derive the general conditions for achieving the maximum expected Sharpe ratio. We derive static rules for achieving the maximum Sharpe ratio with two or more options, as well as a continuum of derivative contracts. The optimal strategy has a truncated right tail and a fat left tail. We also derive dynamic rules for increasing the Sharpe ratio. O...

  5. The application of phase analysis of gated myocardial perfusion imaging to assess left ventricular mechanical dyssynchrony in cardiovascular disease

    Wang Jianfeng; Wang Yuetao

    2013-01-01

    Left ventricular mechanical dyssynchrony is closely related to the severity of cardiovascular disease, it is essential to assess left ventricular mechanical dyssynchrony accurately for early prediction of adverse cardiac events and prognosis assessment of the cardiac resynchronization therapy. As a new technology to assess left ventricular mechanical dyssynchrony, the phase analysis of gated myocardial perfusion imaging (GMPI) can get both quantitative indicators of regional myocardial perfusion, evaluation of regional myocardial viability and scar tissue, as well as quantitative analysis of left ventricular function and left ventricular mechanical synchrony, it has broad application prospects in cardiovascular disease to assess left ventricular mechanical dyssynchrony and prognosis assessment. This review mainly described the applications of GMPI phase analysis in the cardiovascular disease. (authors)

  6. Increased platelet aggregation and turnover in the acute phase of ST-elevation myocardial infarction

    Jensen, Kristian Løkke Funck; Dalsgaard, Jens; Grove, Erik Lerkevang

    2013-01-01

    Newly produced platelets are present in the acute phase of ST-elevation myocardial infarction (STEMI). This may influence the antiplatelet effect of aspirin and clopidogrel administered prior to primary percutaneous coronary intervention (PPCI). The aims of this study were to investigate the anti...... turnover may partly explain the reduced efficacy of antiplatelet drugs in the acute phase of STEMI....... the antiplatelet effect of aspirin and clopidogrel and evaluate platelet turnover in the acute phase of STEMI compared to a stable phase 3 months later. In this observational follow-up study on 48 STEMI patients transferred for PPCI, loading doses of aspirin (300 mg) and clopidogrel (600 mg) were given orally...... in the ambulance. Blood samples were obtained immediately prior to PPCI, at 4 and 12 hours after administration of bolus doses and at follow-up after 3 months. Residual platelet aggregation was evaluated by Multiplate® and VerifyNow® aggregometry. Platelet turnover was evaluated by automated flow cytometry...

  7. SHARP User Manual

    Yu, Y. Q. [Argonne National Lab. (ANL), Argonne, IL (United States); Shemon, E. R. [Argonne National Lab. (ANL), Argonne, IL (United States); Thomas, J. W. [Argonne National Lab. (ANL), Argonne, IL (United States); Mahadevan, Vijay S. [Argonne National Lab. (ANL), Argonne, IL (United States); Rahaman, Ronald O. [Argonne National Lab. (ANL), Argonne, IL (United States); Solberg, Jerome [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-03-31

    SHARP is an advanced modeling and simulation toolkit for the analysis of nuclear reactors. It is comprised of several components including physical modeling tools, tools to integrate the physics codes for multi-physics analyses, and a set of tools to couple the codes within the MOAB framework. Physics modules currently include the neutronics code PROTEUS, the thermal-hydraulics code Nek5000, and the structural mechanics code Diablo. This manual focuses on performing multi-physics calculations with the SHARP ToolKit. Manuals for the three individual physics modules are available with the SHARP distribution to help the user to either carry out the primary multi-physics calculation with basic knowledge or perform further advanced development with in-depth knowledge of these codes. This manual provides step-by-step instructions on employing SHARP, including how to download and install the code, how to build the drivers for a test case, how to perform a calculation and how to visualize the results. Since SHARP has some specific library and environment dependencies, it is highly recommended that the user read this manual prior to installing SHARP. Verification tests cases are included to check proper installation of each module. It is suggested that the new user should first follow the step-by-step instructions provided for a test problem in this manual to understand the basic procedure of using SHARP before using SHARP for his/her own analysis. Both reference output and scripts are provided along with the test cases in order to verify correct installation and execution of the SHARP package. At the end of this manual, detailed instructions are provided on how to create a new test case so that user can perform novel multi-physics calculations with SHARP. Frequently asked questions are listed at the end of this manual to help the user to troubleshoot issues.

  8. SHARP User Manual

    Yu, Y. Q.; Shemon, E. R.; Thomas, J. W.; Mahadevan, Vijay S.; Rahaman, Ronald O.; Solberg, Jerome

    2016-01-01

    SHARP is an advanced modeling and simulation toolkit for the analysis of nuclear reactors. It is comprised of several components including physical modeling tools, tools to integrate the physics codes for multi-physics analyses, and a set of tools to couple the codes within the MOAB framework. Physics modules currently include the neutronics code PROTEUS, the thermal-hydraulics code Nek5000, and the structural mechanics code Diablo. This manual focuses on performing multi-physics calculations with the SHARP ToolKit. Manuals for the three individual physics modules are available with the SHARP distribution to help the user to either carry out the primary multi-physics calculation with basic knowledge or perform further advanced development with in-depth knowledge of these codes. This manual provides step-by-step instructions on employing SHARP, including how to download and install the code, how to build the drivers for a test case, how to perform a calculation and how to visualize the results. Since SHARP has some specific library and environment dependencies, it is highly recommended that the user read this manual prior to installing SHARP. Verification tests cases are included to check proper installation of each module. It is suggested that the new user should first follow the step-by-step instructions provided for a test problem in this manual to understand the basic procedure of using SHARP before using SHARP for his/her own analysis. Both reference output and scripts are provided along with the test cases in order to verify correct installation and execution of the SHARP package. At the end of this manual, detailed instructions are provided on how to create a new test case so that user can perform novel multi-physics calculations with SHARP. Frequently asked questions are listed at the end of this manual to help the user to troubleshoot issues.

  9. Selective coronarography and ventriculography with Iopamidol in the acute phase of myocardial infarction

    Ricci Maccarini, P; Benenati, P M; Bellanti, G; Piscitelli, G

    1988-01-01

    The new techniques for an early treatement of acute myocardial infarction (AMI), such as thrombolysis and percutaneous transluminal angioplasty, often necessitate rapid and accurate radiological evaluation of coronaric lesions and left ventricular function. The aim of the present study was to evaluate both safety and tolerability of selective coronarography (SC) and left ventriculography (LVG), with iopamidol 370 mg I/ml as a contrast medium, in the acute phase of AMI. Thirty-nine patients aged 26-29 years, were examined: 18 group A, within 4 days (mean 2.6+-0.8 SD) and 21, group B, within 5-15 days after AMI (mean 8.8+-3 SD). Contrast media (cm) dosage varied from 150 to 300 ml (2.43-5.5 ml/bw). During the procedure, ECG was continuosly recorded; left ventricular pressure was registered immediately and 30 minutes after cm administration. During the following 9 days ECG tracings and plasmatic cytolysisenzymes were monitored. During the examination no patient complained of any symptoms. After LVG slight elevations in end diastolic pressure were detected in all patients (mean increase 4.7 mmHg), which were not relevant from a clinical point of view. In 11/39 cases ventricular tachycardia was observed, which spontaneously ceased. During SC no change in ECG tracings was registered except in one patient, group A, in whom complete transitory heart block was detected. After SC no alteration in instrumental and biochemical parameters was registered except in one patient, group B, in whom a reinfarction due to right coronaric artery occlusion was observed. In conclusion, these results suggest that both SC and LVG with iopamidol are safe techniques also in the early phase of myocardial infarction. 24 refs.

  10. Diagnostic value of amplitude-phase analysis in myocardial infarct. Comparison with thallium perfusion scintigraphy and contrast ventrilography

    Garcheva, M.; Trindev, P.; Shejretova, E.; Stoyanova, N.; Kaloyanova, P.; Khadzhikostova, Kh.

    1990-01-01

    The evaluation is based on the results of investigation of 34 patients who have had myocardial infarct without rhythm disturbances. Compared to contrast ventrilography, the amplitude-phase analysis (APA) of 'rest' radionuclide ventrilography show 80% sensitivity and 100% specificity, as well as high accuracy in determination of the type and localization of the kinetic disturbances. The comparison with the thallium perfusion scintigraphy demonstrates the possibility of APA to vizualize abnormal kinetic area of the myocardial wall and shows its independent significance in the cases of doubtful findings. APA is a powerful tool for unambigious differentiating of hypokinetic from akinetic and diskinetic areas. 1 tab., 1 fig., 4 refs

  11. Almost sharp quantum effects

    Arias, Alvaro; Gudder, Stan

    2004-01-01

    Quantum effects are represented by operators on a Hilbert space satisfying 0≤A≤I, and sharp quantum effects are represented by projection operators. We say that an effect A is almost sharp if A=PQP for projections P and Q. We give simple characterizations of almost sharp effects. We also characterize effects that can be written as longer products of projections. For generality we first work in the formalism of von Neumann algebras. We then specialize to the full operator algebra B(H) and to finite dimensional Hilbert spaces

  12. Fasa Registry on Acute Myocardial Infarction (FaRMI: Feasibility Study and Pilot Phase Results.

    Ehsan Bahramali

    Full Text Available Myocardial infarction (MI is the leading cause of death in Iran. Every attempt to improve treatment patterns and patient outcomes needs a surveillance system to both consider the efficacy and safety measures. Fasa Registry on Myocardial Infarction (FaRMI is the first population-based registry for acute MI in Iran targeted to provide meticulous description of patients' characteristics, to explore the management patterns of these patients, to discover the degree of adherence to the practice guidelines, and to investigate the determinants of poor in-hospital and later outcomes.A diagnosis of acute MI (type I, II and III was made upon the accepted criteria by the attending cardiologists and types IV and V MI were excluded. Two registrar nurses gathered data on demographics, place of residence and ethnicity, past medical history, risk factors, and the clinical course. Management patterns in the pre-hospital setting, during the hospital stay and at the discharge time were recorded. Routine laboratory results and cardiac biomarkers on three consecutive days were registered.pilot phase included the first 95 patients, 63.5% of whom were men and 31.5% were women. With a mean age of 62.89±13.75 years among participants, the rate of premature MI was 31.8%. ST segment elevation MI accounted for 68.2% cases and inferior wall was the most prevalent region involved followed by anterior and posterior walls.Obtained data on the characteristics of patients suffering an MI event revealed the major determinants of delay in initiation of therapies and contributors of poor outcome. Completeness of data was guaranteed upon involvement of multiple checkpoints and data quality was secured by means of automatic validation processes in addition to weekly physicians' roundups.Execution of FaRMI in the form presented is feasible and it will build up a comprehensive population-based registry for MI in the region.

  13. SHARP Multiphysics Tutorials

    Yu, Y. Q. [Argonne National Lab. (ANL), Argonne, IL (United States); Shemon, E. R. [Argonne National Lab. (ANL), Argonne, IL (United States); Mahadevan, Vijay S. [Argonne National Lab. (ANL), Argonne, IL (United States); Rahaman, Ronald O. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-02-29

    SHARP, developed under the NEAMS Reactor Product Line, is an advanced modeling and simulation toolkit for the analysis of advanced nuclear reactors. SHARP is comprised of three physics modules currently including neutronics, thermal hydraulics, and structural mechanics. SHARP empowers designers to produce accurate results for modeling physical phenomena that have been identified as important for nuclear reactor analysis. SHARP can use existing physics codes and take advantage of existing infrastructure capabilities in the MOAB framework and the coupling driver/solver library, the Coupled Physics Environment (CouPE), which utilizes the widely used, scalable PETSc library. This report aims at identifying the coupled-physics simulation capability of SHARP by introducing the demonstration example called sahex in advance of the SHARP release expected by Mar 2016. sahex consists of 6 fuel pins with cladding, 1 control rod, sodium coolant and an outer duct wall that encloses all the other components. This example is carefully chosen to demonstrate the proof of concept for solving more complex demonstration examples such as EBR II assembly and ABTR full core. The workflow of preparing the input files, running the case and analyzing the results is demonstrated in this report. Moreover, an extension of the sahex model called sahex_core, which adds six homogenized neighboring assemblies to the full heterogeneous sahex model, is presented to test homogenization capabilities in both Nek5000 and PROTEUS. Some primary information on the configuration and build aspects for the SHARP toolkit, which includes capability to auto-download dependencies and configure/install with optimal flags in an architecture-aware fashion, is also covered by this report. A step-by-step instruction is provided to help users to create their cases. Details on these processes will be provided in the SHARP user manual that will accompany the first release.

  14. SHARP Multiphysics Tutorials

    Yu, Y. Q.; Shemon, E. R.; Mahadevan, Vijay S.; Rahaman, Ronald O.

    2016-01-01

    SHARP, developed under the NEAMS Reactor Product Line, is an advanced modeling and simulation toolkit for the analysis of advanced nuclear reactors. SHARP is comprised of three physics modules currently including neutronics, thermal hydraulics, and structural mechanics. SHARP empowers designers to produce accurate results for modeling physical phenomena that have been identified as important for nuclear reactor analysis. SHARP can use existing physics codes and take advantage of existing infrastructure capabilities in the MOAB framework and the coupling driver/solver library, the Coupled Physics Environment (CouPE), which utilizes the widely used, scalable PETSc library. This report aims at identifying the coupled-physics simulation capability of SHARP by introducing the demonstration example called sahex in advance of the SHARP release expected by Mar 2016. sahex consists of 6 fuel pins with cladding, 1 control rod, sodium coolant and an outer duct wall that encloses all the other components. This example is carefully chosen to demonstrate the proof of concept for solving more complex demonstration examples such as EBR II assembly and ABTR full core. The workflow of preparing the input files, running the case and analyzing the results is demonstrated in this report. Moreover, an extension of the sahex model called sahex c ore, which adds six homogenized neighboring assemblies to the full heterogeneous sahex model, is presented to test homogenization capabilities in both Nek5000 and PROTEUS. Some primary information on the configuration and build aspects for the SHARP toolkit, which includes capability to auto-download dependencies and configure/install with optimal flags in an architecture-aware fashion, is also covered by this report. A step-by-step instruction is provided to help users to create their cases. Details on these processes will be provided in the SHARP user manual that will accompany the first release.

  15. The SHARP scramjet launcher

    Cartland, H.; Fiske, P.; Greenwood, R.; Hargiss, D.; Heston, P.; Hinsey, N.; Hunter, J.; Massey, W.

    1995-01-10

    The worlds largest light gas gun at SHARP (Super High Altitude Research Project) is completed and in the past year has launched 9 scramjets. Typical masses and velocities are 5.9 kg at 2.8 km/sec.and 4.4 kg at 3.1 km/sec. In so doing SHARP launched the first fully functioning, hydrogen burning scramjet at mach 8. The SHARP launcher is unique in having a 4 inch diameter and 155 foot-long barrel. This enables lower acceleration launches than any other system. In addition the facility can deliver high energy projectiles to targets in the open air without having to contain the impact fragments. This allows one to track lethality test debris for several thousand feet.

  16. Evaluation of the prevalence of stress and its phases in acute myocardial infarction in patients active in the labor market

    Luciane Boreki Lucinda

    2015-02-01

    Full Text Available Introduction: Acute myocardial infarction is a social health problem of epidemiological relevance, with high levels of morbidity and mortality. Stress is one of the modifiable risk factors that triggers acute myocardial infarction. Stress is a result of a set of physiological reactions, which when exaggerated in intensity or duration can lead to imbalances in one's organism, resulting in vulnerability to diseases. Objective: To identify the presence of stress and its phases in hospitalized and active labor market patients with unstable myocardial infarction and observe its correlation with the life of this population with stress. Methods: The methodology used was a quantitative, descriptive and transversal research approach conducted with a total of 43 patients, who were still active in the labor market, presenting or not morbidities. Data collection occurred on the fourth day of their hospitalization and patients responded to Lipp's Stress Symptom Inventory for adults. Results: Thirty-one patients (72.1% presented stress and twelve (27.8% did not. In patients with stress, the identified phases were: alert - one patient (3.2%; resistance -twenty-two patients (71.0%; quasi-exhaustion - six patients (19.4% and exhaustion - two patients (6.5%. All women researched presented stress. Conclusion: The results suggest a high level of stress, especially in the resistance phase, in the male infarcted population, hospitalized and active in the labor market.

  17. Sharp spatially constrained inversion

    Vignoli, Giulio G.; Fiandaca, Gianluca G.; Christiansen, Anders Vest C A.V.C.

    2013-01-01

    We present sharp reconstruction of multi-layer models using a spatially constrained inversion with minimum gradient support regularization. In particular, its application to airborne electromagnetic data is discussed. Airborne surveys produce extremely large datasets, traditionally inverted...... by using smoothly varying 1D models. Smoothness is a result of the regularization constraints applied to address the inversion ill-posedness. The standard Occam-type regularized multi-layer inversion produces results where boundaries between layers are smeared. The sharp regularization overcomes...... inversions are compared against classical smooth results and available boreholes. With the focusing approach, the obtained blocky results agree with the underlying geology and allow for easier interpretation by the end-user....

  18. Dictionary-driven Ischemia Detection from Cardiac Phase-Resolved Myocardial BOLD MRI at Rest

    Bevilacqua, Marco; Dharmakumar, Rohan; Tsaftaris, Sotirios A.

    2016-01-01

    Cardiac Phase-resolved Blood-Oxygen-Level Dependent (CP–BOLD) MRI provides a unique opportunity to image an ongoing ischemia at rest. However, it requires post-processing to evaluate the extent of ischemia. To address this, here we propose an unsupervised ischemia detection (UID) method which relies on the inherent spatio-temporal correlation between oxygenation and wall motion to formalize a joint learning and detection problem based on dictionary decomposition. Considering input data of a single subject, it treats ischemia as an anomaly and iteratively learns dictionaries to represent only normal observations (corresponding to myocardial territories remote to ischemia). Anomaly detection is based on a modified version of One-class Support Vector Machines (OCSVM) to regulate directly the margins by incorporating the dictionary-based representation errors. A measure of ischemic extent (IE) is estimated, reflecting the relative portion of the myocardium affected by ischemia. For visualization purposes an ischemia likelihood map is created by estimating posterior probabilities from the OCSVM outputs, thus obtaining how likely the classification is correct. UID is evaluated on synthetic data and in a 2D CP–BOLD data set from a canine experimental model emulating acute coronary syndromes. Comparing early ischemic territories identified with UID against infarct territories (after several hours of ischemia), we find that IE, as measured by UID, is highly correlated (Pearson’s r = 0.84) w.r.t. infarct size. When advances in automated registration and segmentation of CP–BOLD images and full coverage 3D acquisitions become available, we hope that this method can enable pixel-level assessment of ischemia with this truly non-invasive imaging technique. PMID:26292338

  19. Optimal left ventricular lead position assessed with phase analysis on gated myocardial perfusion SPECT

    Boogers, Mark J.; Chen, Ji; Garcia, Ernest V.; Bommel, Rutger J. van; Borleffs, C.J.W.; Schalij, Martin J.; Wall, Ernst E. van der; Bax, Jeroen J.; Dibbets-Schneider, Petra; Hiel, Bernies van der; Younis, Imad Al

    2011-01-01

    The aim of the current study was to evaluate the relationship between the site of latest mechanical activation as assessed with gated myocardial perfusion SPECT (GMPS), left ventricular (LV) lead position and response to cardiac resynchronization therapy (CRT). The patient population consisted of consecutive patients with advanced heart failure in whom CRT was currently indicated. Before implantation, 2-D echocardiography and GMPS were performed. The echocardiography was performed to assess LV end-systolic volume (LVESV), LV end-diastolic volume (LVEDV) and LV ejection fraction (LVEF). The site of latest mechanical activation was assessed by phase analysis of GMPS studies and related to LV lead position on fluoroscopy. Echocardiography was repeated after 6 months of CRT. CRT response was defined as a decrease of ≥15% in LVESV. Enrolled in the study were 90 patients (72% men, 67±10 years) with advanced heart failure. In 52 patients (58%), the LV lead was positioned at the site of latest mechanical activation (concordant), and in 38 patients (42%) the LV lead was positioned outside the site of latest mechanical activation (discordant). CRT response was significantly more often documented in patients with a concordant LV lead position than in patients with a discordant LV lead position (79% vs. 26%, p<0.01). After 6 months, patients with a concordant LV lead position showed significant improvement in LVEF, LVESV and LVEDV (p<0.05), whereas patients with a discordant LV lead position showed no significant improvement in these variables. Patients with a concordant LV lead position showed significant improvement in LV volumes and LV systolic function, whereas patients with a discordant LV lead position showed no significant improvements. (orig.)

  20. Absolute coronary blood flow measurement and microvascular resistance in ST-elevation myocardial infarction in the acute and subacute phase

    Wijnbergen, Inge; Veer, Marcel van ' t [Department of Cardiology, Catharina Hospital, Eindhoven (Netherlands); Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven (Netherlands); Lammers, Jeroen; Ubachs, Joey [Department of Cardiology, Catharina Hospital, Eindhoven (Netherlands); Pijls, Nico H.J., E-mail: nico.pijls@cze.nl [Department of Cardiology, Catharina Hospital, Eindhoven (Netherlands); Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven (Netherlands)

    2016-03-15

    Background/Purpose: In a number of patients with acute myocardial infarction (AMI), myocardial hypoperfusion, known as the no-reflow phenomenon, persists after primary percutaneous intervention (PPCI). The aim of this study was to evaluate the feasibility and safety of a new quantitative method of measuring absolute blood flow and resistance within the perfusion bed of an infarct-related artery. Furthermore, we sought to study no-reflow by correlating these measurements to the index of microvascular resistance (IMR) and the area at risk (AR) as determined by cardiac magnetic resonance imaging (CMR). Methods: Measurements of absolute flow and myocardial resistance were performed in 20 patients with ST-segment elevation myocardial infarction (STEMI), first immediately following PPCI and then again after 3–5 days. These measurements used the technique of thermodilution during a continuous infusion of saline. Flow was expressed in ml/min per gram of tissue within the area at risk. Results: The average time needed for measurement of absolute flow, resistance and IMR was 20 min, and all measurements could be performed without complication. A higher flow supplying the AR correlated with a lower IMR in the acute phase. Absolute flow increased from 3.14 to 3.68 ml/min/g (p = 0.25) and absolute resistance decreased from 1317 to 1099 dyne.sec.cm-5/g (p = 0.40) between the first day and fifth day after STEMI. Conclusions: Measurement of absolute flow and microvascular resistance is safe and feasible in STEMI patients and may allow for a better understanding of microvascular (dys)function in the early phase of AMI. - Highlights: • We measured absolute coronary blood flow and microvascular resistance in STEMI patients in the acute phase and in the subacute phase, using the technique of thermodilution with low grade intracoronary continuous infusion of saline. • These measurements are safe and feasible during PPCI in STEMI patients. • In STEMI patients, absolute flow

  1. Software design of SHARP

    Siegel, A.; Tautges, T.; Caceres, A.; Kaushik, D.; Fischer, P.; Palmiotti, G.; Smith, M.; Ragusa, J.

    2007-01-01

    SHARP (Simulation-based High-efficiency Advanced Reactor Prototyping) is a modern suite of codes to simulate the key components of a fast reactor core. The SHARP tool-kit is organized as a collection of modules, each representing the key components of the physics to be modeled - neutron transport, thermal hydraulics, fuel/structure behavior - together with pre and post-processing for geometry definition, mesh generation, visualization, user interface, etc. The physics models are designed to make minimal possible use of lumped parameter models, homogenization, and empirical correlations in favor of more direct solution of the fundamental governing equations, when sufficient computing resources are available. Thus, one of the key design goals is to effectively leverage leadership class computing resources - viz. BG/P and Cray Supercomputers that are on the current trajectory to delivering sustained peta-flops performance. Further, the nature of the physical problem to be investigated will require either strong or weak coupling between some or all of the existing modules (e.g. operator split vs. fully coupled), while multiple implementations of each physics module, representing different algorithms, will also be required (e.g. deterministic versus Monte Carlo) for verification and to explore different physical regimes. Accomplishing these goals in the context of ultra-scalable architectures and multidisciplinary and possibly distributed development teams is a daunting task. In this paper we explain our initial lightweight and loosely coupled framework, its initial design, and a number of current open research questions in this area. (authors)

  2. A framework to measure myocardial extracellular volume fraction using dual-phase low dose CT images

    Liu, Yixun; Summers, Ronald M.; Yao, Jianhua; Liu, Songtao; Sibley, Christopher T.; Bluemke, David A.; Nacif, Marcelo S.

    2013-01-01

    Purpose: Myocardial extracellular volume fraction (ECVF) is a surrogate imaging biomarker of diffuse myocardial fibrosis, a hallmark of pathologic ventricular remodeling. Low dose cardiac CT is emerging as a promising modality to detect diffuse interstitial myocardial fibrosis due to its fast acquisition and low radiation; however, the insufficient contrast in the low dose CT images poses great challenge to measure ECVF from the image. Methods: To deal with this difficulty, the authors present a complete ECVF measurement framework including a point-guided myocardial modeling, a deformable model-based myocardium segmentation, nonrigid registration of pre- and post-CT, and ECVF calculation. Results: The proposed method was evaluated on 20 patients by two observers. Compared to the manually delineated reference segmentations, the accuracy of our segmentation in terms of true positive volume fraction (TPVF), false positive volume fraction (FPVF), and average surface distance (ASD), were 92.18% ± 3.52%, 0.31% ± 0.10%, 0.69 ± 0.14 mm, respectively. The interobserver variability measured by concordance correlation coefficient regarding TPVF, FPVF, and ASD were 0.95, 0.90, 0.94, respectively, demonstrating excellent agreement. Bland-Altman method showed 95% limits of agreement between ECVF at CT and ECVF at MR. Conclusions: The proposed framework demonstrates its efficiency, accuracy, and noninvasiveness in ECVF measurement and dramatically advances the ECVF at cardiac CT toward its clinical use

  3. A framework to measure myocardial extracellular volume fraction using dual-phase low dose CT images

    Liu, Yixun; Summers, Ronald M.; Yao, Jianhua, E-mail: JYao@cc.nih.gov [Clinical Image Processing Service, Radiology and Imaging Sciences, NIH Clinical Center, Bethesda, Maryland 20892 (United States); Liu, Songtao; Sibley, Christopher T.; Bluemke, David A. [Radiology and Imaging Sciences, NIH Clinical Center, Bethesda, Maryland 20892-1182 and Molecular Biomedical Imaging Laboratory, National Institute of Biomedical Imaging and Bioengineering, NIH Clinical Center, Bethesda, Maryland 20892 (United States); Nacif, Marcelo S. [Radiology and Imaging Sciences, NIH Clinical Center, Bethesda, Maryland 20892-1182 (United States)

    2013-10-15

    Purpose: Myocardial extracellular volume fraction (ECVF) is a surrogate imaging biomarker of diffuse myocardial fibrosis, a hallmark of pathologic ventricular remodeling. Low dose cardiac CT is emerging as a promising modality to detect diffuse interstitial myocardial fibrosis due to its fast acquisition and low radiation; however, the insufficient contrast in the low dose CT images poses great challenge to measure ECVF from the image. Methods: To deal with this difficulty, the authors present a complete ECVF measurement framework including a point-guided myocardial modeling, a deformable model-based myocardium segmentation, nonrigid registration of pre- and post-CT, and ECVF calculation. Results: The proposed method was evaluated on 20 patients by two observers. Compared to the manually delineated reference segmentations, the accuracy of our segmentation in terms of true positive volume fraction (TPVF), false positive volume fraction (FPVF), and average surface distance (ASD), were 92.18% ± 3.52%, 0.31% ± 0.10%, 0.69 ± 0.14 mm, respectively. The interobserver variability measured by concordance correlation coefficient regarding TPVF, FPVF, and ASD were 0.95, 0.90, 0.94, respectively, demonstrating excellent agreement. Bland-Altman method showed 95% limits of agreement between ECVF at CT and ECVF at MR. Conclusions: The proposed framework demonstrates its efficiency, accuracy, and noninvasiveness in ECVF measurement and dramatically advances the ECVF at cardiac CT toward its clinical use.

  4. Myocardial Bridge

    ... Center > Myocardial Bridge Menu Topics Topics FAQs Myocardial Bridge En español Your heart is made of muscle, ... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart ...

  5. Quantitative relationships between thallium-201 estimated myocardial infarct size and left ventricular function in the acute or convalescent phase of the first attack of myocardial infarction

    Kataoka, Hajime (Kagoshima Univ. (Japan). Faculty of Medicine); Ueda, Keiji; Sakai, Makoto (and others)

    1983-07-01

    Correlations between left ventricular (LV) function and infarct size estimated by computer-assisted thallium (Tl)-201 scintigraphy were studied in 16 patients in the acute or convalescent phase of the first attack of transmural myocardial infarction (MI). Tl-201 estimation of the infarct size was done using a ''corrected'' circumferential profile method, by which the total defect score could be obtained. The LV function was evaluated by radionuclide angiography, echocardiography and cardiac catheterization study. The following results were obtained: 1) A close inverse relationship was found between the defect score and the ejection fraction (r = -0.649, p < 0.01). 2) The linear correlation coefficient was 0.540 (p < 0.05) between the defect score and the pulmonary arterial end-diastolic pressure and -0.616 (p < 0.02) between the defect score and the stroke volume index. There was no significant correlation between the defect score and the cardiac index. 3) There was a linear correlation between the defect score and the LV end-diastolic dimension (r = -0.852, p < 0.001). However, there was no relation between the defect score and the left atrial dimension. When the LV indices were compared between the small (S) and the large (L) defect score group, the L defect group had faster heart rate, larger LV chamber size and the smaller stroke volume index than the S defect group. However, there was no significant difference in the cardiac index between these 2 groups. These results suggest that the LV dilatation in acute or convalescent phase of the first attack of transmural MI is an ominous sign because it was usually accompanied by large infarct size. The present study also indicates that LV dilatation accompanying a large infarct does not satisfactorily compensate for LV dysfunction by Frank-Starling mechanism.

  6. The diagnostic value of Tc-99m PYP, Tl-201 dual isotope SPECT to predict the viability of damaged myocardium in the acute phase of myocardial infarction

    Matsuo, Hitoshi; Watanabe, Sachiro; Arai, Masazumi

    1991-01-01

    To assess the diagnostic value of Tc-99m pyrophosphate (PYP), Tl-201 dual isotope SPECT for the evaluation of myocardial viability, segmental comparison between dual isotope SPECT and exercise, delayed, and reinjected Tl study were performed with 18 acute myocardial infarction (AMI) patients. Among 72 damaged myocardial segments, 48 segments (67%) were judged as viable by chronic phase Tl studies. The segments with severely reduced Tl uptake by dual SPECT showed significantly lower prevalence of viable myocardium than the segments with reduced and normal Tl uptake (p<0.001). The segments with PYP accumulation localized to the subendocardium represented the favorable outcome compared with the transmural accumulation (p<0.001). And overlap segments show better prognosis than the segments without overlap (p<0.05). Most importantly, we can get better predictive accuracy of myocardial scar by dual isotope SPECT than the judgement by Tl or PYP SPECT alone (83.3% vs 77.8%, 68.1%). Thus, we conclude that Tc-99m PYP, Tl-201 dual isotope SPECT is useful to assess the severity of myocardial damage in the acute phase of myocardial infarction. (author)

  7. Left ventricular regional myocardial motion and twist function in repaired tetralogy of Fallot evaluated by magnetic resonance tissue phase mapping

    Chang, Meng-Chu; Peng, Hsu-Hsia; Wu, Ming-Ting; Weng, Ken-Pen; Su, Mao-Yuan; Menza, Marius; Huang, Hung-Chieh

    2018-01-01

    We aimed to characterise regional myocardial motion and twist function in the left ventricles (LV) in patients with repaired tetralogy of Fallot (rTOF) and preserved LV global function. We recruited 47 rTOF patients and 38 age-matched normal volunteers. Tissue phase mapping (TPM) was performed for evaluating the LV myocardial velocity in longitudinal, radial, and circumferential (Vz, Vr, and VOe) directions in basal, middle, and apical slices. The VOe peak-to-peak (PTP) during systolic phases, the rotation angle of each slice, and VOe inconsistency were computed for evaluating LV twist function and VOe dyssynchrony. As compared to the controls, the rTOF patients presented decreased RV ejection fraction (RVEF) (p = 0.002) and preserved global LV ejection fraction (LVEF). They also demonstrated decreased systolic and diastolic Vz in several LV segments and higher diastolic Vr in the septum (all p < 0.05). A lower VOe PTP, higher VOe inconsistency, and reduced peak net rotation angle (all p < 0.05) were observed. The aforementioned indices demonstrated an altered LV twist function in rTOF patients in an early disease stage. MR TPM could provide information about early abnormalities of LV regional motion and twist function in rTOF patients with preserved LV global function. (orig.)

  8. Left ventricular regional myocardial motion and twist function in repaired tetralogy of Fallot evaluated by magnetic resonance tissue phase mapping

    Chang, Meng-Chu; Peng, Hsu-Hsia [National Tsing Hua University, Department of Biomedical Engineering and Environmental Sciences, Hsinchu (China); Wu, Ming-Ting [Kaohsiung Veterans General Hospital, Department of Radiology, Kaohsiung (China); National Yang-Ming University, Faculty of Medicine, Taipei (China); Weng, Ken-Pen [National Yang-Ming University, Faculty of Medicine, Taipei (China); Kaohsiung Veterans General Hospital, Department of Pediatrics, Kaohsiung (China); Shu-Zen Junior College of Medicine and Management, Department of Physical Therapy, Kaohsiung (China); Su, Mao-Yuan [National Taiwan University Hospital, Department of Medical Imaging, Taipei (China); Menza, Marius [Medical Center University of Freiburg, Faculty of Medicine, University of Freiburg, Department of Radiology, Medical Physics, Freiburg (Germany); Huang, Hung-Chieh [Kaohsiung Veterans General Hospital, Department of Radiology, Kaohsiung (China)

    2018-01-15

    We aimed to characterise regional myocardial motion and twist function in the left ventricles (LV) in patients with repaired tetralogy of Fallot (rTOF) and preserved LV global function. We recruited 47 rTOF patients and 38 age-matched normal volunteers. Tissue phase mapping (TPM) was performed for evaluating the LV myocardial velocity in longitudinal, radial, and circumferential (Vz, Vr, and VOe) directions in basal, middle, and apical slices. The VOe peak-to-peak (PTP) during systolic phases, the rotation angle of each slice, and VOe inconsistency were computed for evaluating LV twist function and VOe dyssynchrony. As compared to the controls, the rTOF patients presented decreased RV ejection fraction (RVEF) (p = 0.002) and preserved global LV ejection fraction (LVEF). They also demonstrated decreased systolic and diastolic Vz in several LV segments and higher diastolic Vr in the septum (all p < 0.05). A lower VOe PTP, higher VOe inconsistency, and reduced peak net rotation angle (all p < 0.05) were observed. The aforementioned indices demonstrated an altered LV twist function in rTOF patients in an early disease stage. MR TPM could provide information about early abnormalities of LV regional motion and twist function in rTOF patients with preserved LV global function. (orig.)

  9. Clinical aspects of coronary heart diseases without myocardial infarction and in the chronic infarction phase

    Kober, G.

    1984-01-01

    Reductions in coronary vessel diameters of more than 50% are usually caused by atherosclerosis, seldom by predominant spasme. They can lead via an inadequate myocardial perfusion to angina pectoris. Whereas in patients with organic coronary stenoses exertional angina is typical, patients with coronary spasms usually tend to angina at rest. Depending on the symptoms, a stable or unstable angina can be distinguished from the status anginosus and a variant form of angina. During anginal attacks signs of myocardial ischemia can often be seen in the electrocardiogram. This applies to patients with and without earlier myocardial infarctions. When pathologic ECG-changes can already be seen in the ECG at rest, difficulties often arise during evaluation of the exercise-ECG. In those cases, diagnosis can be improved by additional investigations, especially with radionuclear techniques. For a conclusive diagnosis, left heart catheterization and a functional coronary angiography is necessary. Coronary heart disease can be treated either by drug therapy, coronary angioplasty or bypass surgery. The same diagnostic procedures are suitable for the evaluation of a therapeutical success and for primary diagnosis. (orig.) [de

  10. Dexrazoxane Shows No Protective Effect in the Acute Phase of Reperfusion during Myocardial Infarction in Pigs.

    Kamat, Pranitha; Vandenberghe, Stijn; Christen, Stephan; Bongoni, Anjan K; Meier, Bernhard; Rieben, Robert; Khattab, Ahmed A

    2016-01-01

    Calcium and iron overload participate in the mechanisms of ischemia/reperfusion (I/R) injury during myocardial infarction (MI). Calcium overload induces cardiomyocyte death by hypercontraction, while iron catalyses generation of reactive oxygen species (ROS). We therefore hypothesized that dexrazoxane, an intracellular metal chelator, would attenuate I/R injury. MI was induced in pigs by occlusion of the left anterior descending artery for 1 hour followed by 2 hours reperfusion. Thirty minutes before reperfusion either 5 mg/ml dexrazoxane (n = 5) or saline (n = 5) was infused intravenously. Myocardial necrosis as percentage of the area at ischemic risk was found to be similar in both groups (77.2 ± 18% for dexrazoxane and 76.4 ± 14% for saline group) as determined by triphenyl tetrazolium chloride staining of the ischemic myocardium. Also, serum levels of troponin-I were similar in both groups. A conductance catheter was used to measure left ventricular pressure and volume at all times. Markers for tissue damage due to ROS (HNE), endothelial cell activation (CD31) and inflammation (IgG, C3b/c, C5b9, MCP-1) were assessed on tissue and/or in serum. No significant differences were observed between the groups for the parameters analyzed. To conclude, in this clinically relevant model of early reperfusion after acute myocardial ischemia, dexrazoxane lacked attenuating effects on I/R injury as shown by the measured parameters.

  11. Dexrazoxane Shows No Protective Effect in the Acute Phase of Reperfusion during Myocardial Infarction in Pigs.

    Pranitha Kamat

    Full Text Available Calcium and iron overload participate in the mechanisms of ischemia/reperfusion (I/R injury during myocardial infarction (MI. Calcium overload induces cardiomyocyte death by hypercontraction, while iron catalyses generation of reactive oxygen species (ROS. We therefore hypothesized that dexrazoxane, an intracellular metal chelator, would attenuate I/R injury. MI was induced in pigs by occlusion of the left anterior descending artery for 1 hour followed by 2 hours reperfusion. Thirty minutes before reperfusion either 5 mg/ml dexrazoxane (n = 5 or saline (n = 5 was infused intravenously. Myocardial necrosis as percentage of the area at ischemic risk was found to be similar in both groups (77.2 ± 18% for dexrazoxane and 76.4 ± 14% for saline group as determined by triphenyl tetrazolium chloride staining of the ischemic myocardium. Also, serum levels of troponin-I were similar in both groups. A conductance catheter was used to measure left ventricular pressure and volume at all times. Markers for tissue damage due to ROS (HNE, endothelial cell activation (CD31 and inflammation (IgG, C3b/c, C5b9, MCP-1 were assessed on tissue and/or in serum. No significant differences were observed between the groups for the parameters analyzed. To conclude, in this clinically relevant model of early reperfusion after acute myocardial ischemia, dexrazoxane lacked attenuating effects on I/R injury as shown by the measured parameters.

  12. Interface sharpness in the Potts model

    Ruiz, J.

    1989-01-01

    A simple proof is given for the existence of a sharp interface between two ordered phases for the three-dimensional 2 double-prime-state Potts model (n integer). The results show that the roughening temperature of the three-dimensional Potts model is greater than the transition temperature of the two-dimensional Potts model. For a large arbitrary spin integer, it is expected that this roughening temperature is equal to the transition temperature (of the 3D model), i.e., that the interface between two ordered phases is harp up to the transition temperature, at which it is wetted by a film of the disordered phase. It is also expected that for a large arbitrary spin integer, the a-f interface (between an ordered and the disordered phase) is sharp at the transition temperature

  13. Spouses' conceptions of the pre-hospital phase when their partners suffered an acute myocardial infarction--a qualitative analysis.

    Johansson, Ingela; Swahn, Eva; Strömberg, Anna

    2008-09-01

    Delay from onset of acute myocardial infarction symptoms to the delivery of medical care is a major determinant of prognosis. Although studies have explored patient reasons for delay, there are only limited data concerning experiences of the spouse. Was to describe spouses' conceptions of the pre-hospital phase when their partners suffered an acute myocardial infarction. A phenomenographic approach was applied. Fifteen spouses were interviewed rational, and consulting others. The category respecting independence contained: accepting the need for control, marital roles and experiences, restraining emotions, and seeking agreement. Our findings suggest that spouses have a strong influence on the course of events. When accepting the partner's need for control through following earlier marital roles and experiences, restraining own emotions and seeking agreement, this seemed to contribute to delay. However, when the spouse was resourceful by sharing the experience, having knowledge, understanding the severity, being rational and consulting others when needed, this seemed to have a positive influence on the pre-hospital time.

  14. Myocardial perfusion imaging with Technetium-99m Sestamibi and Thallium-201. Results of the phase III clinical trial

    Giering, L.; Haber, S.; Joseph, J.L.; Neacy, W.

    1998-01-01

    Full text: Technetium-99m-Sestamibi (MIBI) has been compared to 201 TI and coronary angiography in a large Phase III clinical trial to assess diagnostic accuracy. Exercise and rest planar (P) and SPECT (S) MIBI, and exercise and redistribution thallium-201 studies were performed in 150 healthy volunteers and 396 patients (379 males; mean age 51.3 years). Prior myocardial infarction was present in 50% of the patients. Sensitivity and specificity for angiographically defined cardiovascular diseases - CAD (>70% stenosis) for planar imaging was 90.3% and 81.3% for MIBI and 91.6% and 50.0% for 201 TI. Agreement was 88.7% MIBI and 84.0% for 201 TI. For SPECT imaging, sensitivity and specificity were 95.1% and 46.0% for MIBI and 92.3% and 39.7% for 201 TI. Agreement was 80.0% for MIBI and 76.1% for 201 TI. Tomographic normality rates were 91.4% and 92.9% for MIBI and 201 TI. Agreement for characterisation of defect type by MIBI and 201 TI SPECT was 82.5%. In females, sensitivity was comparable for both agents. Specificity of MIBI planar and SPECT imaging was higher then for 201 TI (P: 90.9% v. 66.7%; S: 76.2% v. 61.9%). The improved imaging characteristics of MIBI results in better diagnostic confidence when interpreting myocardial perfusion studies especially in women and obese patients

  15. Left ventricular diastolic dyssynchrony assessed with phase analysis of gated myocardial perfusion SPECT: a comparison with tissue Doppler imaging

    Boogers, Mark J.; Veltman, Caroline E.; Chen, Ji; Garcia, Ernest V.; Bommel, Rutger J. van; Mooyaart, Eline A.Q.; Wall, Ernst E. van der; Schalij, Martin J.; Bax, Jeroen J.; Delgado, Victoria; Younis, Imad Al; Hiel, Bernies van der; Dibbets-Schneider, Petra

    2011-01-01

    The aim of the current study was to evaluate the feasibility of phase analysis on gated myocardial perfusion SPECT (GMPS) for the assessment of left ventricular (LV) diastolic dyssynchrony in a head-to-head comparison with tissue Doppler imaging (TDI). The population consisted of patients with end-stage heart failure of New York Heart Association functional class III or IV with a reduced LV ejection fraction of ≤35%. LV diastolic dyssynchrony was calculated using TDI as the maximal time delay between early peak diastolic velocities of two opposing left ventricle walls (diastolic mechanical delay). Significant LV diastolic dyssynchrony was defined as a diastolic mechanical delay of >55 ms on TDI. Furthermore, phase analysis on GMPS was performed to evaluate LV diastolic dyssynchrony; diastolic phase standard deviation (SD) and histogram bandwidth (HBW) were used as markers of LV diastolic dyssynchrony. A total of 150 patients (114 men, mean age 66.0 ± 10.4 years) with end-stage heart failure were enrolled. Both diastolic phase SD (r = 0.81, p 55 ms) showed significantly larger diastolic phase SD (68.1 ± 13.4 vs. 40.7 ± 14.0 , p < 0.01) and diastolic HBW (230.6 ± 54.3 vs. 129.0 ± 55.6 , p < 0.01) as compared to patients without LV diastolic dyssynchrony on TDI (≤55 ms). Finally, phase analysis on GMPS showed a good intra- and interobserver reproducibility for the determination of diastolic phase SD (ICC 0.97 and 0.88) and diastolic HBW (ICC 0.98 and 0.93). Phase analysis on GMPS showed good correlations with TDI for the assessment of LV diastolic dyssynchrony. (orig.)

  16. Sharp and the Jules Verne Launcher

    Hunter, John; Cartland, Harry

    1996-03-01

    Lawrence Livermore National Laboratory (LLNL) has built the worlds largest hydrogen gas gun called SHARP, (Super High Altitude Research Project). Originally designed to launch 5 kg to a 450 km altitude, SHARP is configured horizontally at Site 300 in Tracy, California. SHARP is successfully delivering 5 kg scramjets at Mach 9 in aerophysics tests. Some of the results of the scramjet tests are enlightening and are presented insofar as they are relevant to future launches into space. Using a light gas gun to launch payloads into orbit has been analyzed. We look at LEO (Low Earth Orbit), GEO (Geosynchronous Earth Orbit), and LO (Lunar Orbit). We present a conceptual design for a large light gas gun called the Jules Verne Launcher (JVL). The JVL can deliver 3.3 metric tons to a 500 km low earth orbit. We anticipate one launch per day. We present the history of light gas guns, the SHARP design and performance, and the JVL design. Another section is devoted to the vehicle environment and resultant design. Lastly, we present a cost analysis. Our results indicated that the JVL will be able to deliver 1000 metric tons of payload to LEO yearly. The cost will be 5% of the best US rocket delivery cost. This technology will enable the next phase of man's exploration of space.

  17. [Echocardiographic indices related with acute coronary anatomy in acute phase of myocardial infarction: our experience].

    Belluzzi, Fabio; Ciocca, Anna; Grosso Di Palma, Lucia; Cattaneo, Mattia; Conti, Caterina; Magrini, Fabio

    2011-11-01

    Inferior acute myocardial infarction (IAMI) is often associated with right ventricle involvement (RVAMI). Echocardiogram (Echo) shows the ischemic involvement of the right ventricle with an initial dilatation (RVD) and segmental cinetic abnormalities (RVSCS). During RVAMI the normal convexity of the interatrial septum (IAS) toward right atrium is inverted (IASI). 53 patients with IAMI were studied with ECG, echo and hemodinamic monitoring by a Swan-Ganz catheter. Echo was early performed and patients were subdivided into three groups: 1. IAMI with RVSCS and/or RVD with IASI (12 patients); 2. IAMI with RVSCS and/or RVD without IASI (8 patients); 3. IAMI without VSCS, RVD IASI (33 patients). ECG showed RV involvement only in A and B groups (ST-T segment elevation more than 2 mm in V3 r - V5 r). Echo-Doppler showed no statistically differences between the two groups on RV protodiastolic pression; no hemodinamic differences between the two groups (p = n.s.); no statistically differences in central venous pressure, right ventricular pressure, cardiac output, wedge pressure. Complications (arrhytmias, heart failure, ipotension, pericarditis, 3rd A-V block) were so subdivided: group A: 6 patients (50%); group B: 2 patients (24%); group C: 4 patients (12%) with statistical significance (p41 % in group A (5 patients); 20 % in group B (2 patients); 6 % in group C (2 patients), with p<0.01 between all three groups. Echo after six months showed IASI only in two patients of group A. Patients with IASI revealed complications (residual angina, ventricular ipercinetic arrytmias). IASI in patients with IAMI and RVAMI seems to identify a group with higher risk in developing complications and with a more adverse prognosis.

  18. Left ventricular synchrony assessed by phase analysis of gated myocardial perfusion SPECT imaging in healthy subjects

    Wang Yuetao; Wang Jianfeng; Yang Minfu; Niu Rong

    2013-01-01

    Objective: To investigate the value of Cedars-Sinai quantitative gated SPECT (QGS) phase analysis for left ventricular synchrony assessment in healthy subjects. Methods: Seventy-four healthy subjects (41 males, 33 females,average age: (60±13) years) underwent both rest and exercise 99 Tc m -MIBI G-MPI. QGS software was used to analyze the reconstructed rest gated SPECT images automatically, and then the parameters of left ventricular synchrony including phase bandwidth (BW) and phase standard deviation (SD) were obtained. The influences of gender and age (age<60 years, n=36; age ≥ 60 years, n=38) on left ventricular systolic synchronicity were analyzed. The phase angle for original segmental contraction was measured to determine the onset of the ventricular contraction using 17-segment model. Forty healthy subjects were selected by simple random sampling method to evaluate the intra-observer and interobserver repeatability of QGS phase analysis software. Two-sample t test and linear correlation analysis were used to analyze the data. Results: The BW and SD of left ventricular in healthy subjects were (37.22 ±11.71)°, (11.84±5.39)° respectively. Comparisons between male and female for BW and SD yielded no statistical significance (BW: (36.00±9.70)°, (38.73±13.84)°; SD: (11.88±5.56)°, (11.79±5.26)°; t=0.96 and-0.07, both P>0.05); whereas the older subjects (age≥60 years) had larger BW than the others (age<60 years ; (39.95± 12.65)°, (34.33± 10.00)°; t=-2.11, P<0.05) and no statistical significance was shown for SD between the two age groups ((11.18±4.31)°, (12.54±6.33)°; t=1.08, P>0.05). Of the 74 subjects, the mechanical activation started from the ventricular base to apex in 54 subjects (73%), and from apex to base in only 20 subjects (27%). High repeatability of phase analysis was observed for both intra-observer and inter-observer (r=0.867-0.906, all P<0.001). Conclusions: Good left ventricular segmental synchrony is shown in healthy

  19. Cardiac index after acute ST-segment elevation myocardial infarction measured with phase-contrast cardiac magnetic resonance imaging

    Klug, Gert; Reinstadler, Sebastian Johannes; Feistritzer, Hans-Josef; Schwaiger, Johannes P.; Reindl, Martin; Mair, Johannes; Mueller, Silvana; Franz, Wolfgang-Michael; Metzler, Bernhard; Kremser, Christian; Mayr, Agnes

    2016-01-01

    Phase-contrast CMR (PC-CMR) might provide a fast and robust non-invasive determination of left ventricular function in patients after ST-segment elevation myocardial infarction (STEMI). Cine sequences in the left-ventricular (LV) short-axis and free-breathing, retrospectively gated PC-CMR were performed in 90 patients with first acute STEMI and 15 healthy volunteers. Inter- and intra-observer agreement was determined. The correlations of clinical variables age, gender, ejection fraction, NT pro-brain natriuretic peptide [NT-proBNP] with cardiac index (CI) were calculated. For CI, there was a strong agreement of cine CMR with PC-CMR in healthy volunteers (r: 0.82, mean difference: -0.14 l/min/m 2 , error ± 23 %). Agreement was lower in STEMI patients (r: 0.61, mean difference: -0.17 l/min/m 2 , error ± 32 %). In STEMI patients, CI measured with PC-CMR showed lower intra-observer (1 % vs. 9 %) and similar inter-observer variability (9 % vs. 12 %) compared to cine CMR. CI was significantly correlated with age, ejection fraction and NT-proBNP values in STEMI patients. The agreement of PC-CMR and cine CMR for the determination of CI is lower in STEMI patients than in healthy volunteers. After acute STEMI, CI measured with PC-CMR decreases with age, LV ejection fraction and higher NT-proBNP. (orig.)

  20. Early spontaneous intermittent myocardial reperfusion during acute myocardial infarction is associated with augmented thrombogenic activity and less myocardial damage

    Haider, A.W.; Andreotti, F.; Hackett, D.R.; Tousoulis, D.; Kluft, C.; Maseri, A.; Davies, G.J.

    1995-01-01

    Objectives. This study investigated the influence of early spontaneous intermittent reperfusion on the extent of myocardial damage and its relation to endogenous hemostatic activity, Background. In the early phase of acute myocardial infarction coronary occlusion is often intermittent, even before

  1. Assessment of myocardial bridge by cardiac CT: Intracoronary transluminal attenuation gradient derived from diastolic phase predicts systolic compression

    Yu, Meng Meng; Zhang, Yang; Li, Yue Hua; Li, Wen Bin; Li, Ming Hua; Zhang, Jiayin [Institute of Diagnostic and Interventional Radiology, Shanghai Jiao Tong University Affiliated Sixth People' s Hospital, Shangha (China)

    2017-08-01

    To study the predictive value of transluminal attenuation gradient (TAG) derived from diastolic phase of coronary computed tomography angiography (CCTA) for identifying systolic compression of myocardial bridge (MB). Consecutive patients diagnosed with MB based on CCTA findings and without obstructive coronary artery disease were retrospectively enrolled. In total, 143 patients with 144 MBs were included in the study. Patients were classified into three groups: without systolic compression, with systolic compression < 50%, and with systolic compression ≥ 50%. TAG was defined as the linear regression coefficient between intraluminal attenuation in Hounsfield units (HU) and length from the vessel ostium. Other indices such as the length and depth of the MB were also recorded. TAG was the lowest in MB patients with systolic compression ≥ 50% (-19.9 ± 8.7 HU/10 mm). Receiver operating characteristic curve analysis was performed to determine the optimal cutoff values for identifying systolic compression ≥ 50%. The result indicated an optimal cutoff value of TAG as -18.8 HU/10 mm (area under curve = 0.778, p < 0.001), which yielded higher sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy (54.1, 80.5, 72.8, and 75.0%, respectively). In addition, the TAG of MB with diastolic compression was significantly lower than the TAG of MB without diastolic compression (-21.4 ± 4.8 HU/10 mm vs. -12.7 ± 8 HU/10 mm, p < 0.001). TAG was a better predictor of MB with systolic compression ≥ 50%, compared to the length or depth of the MB. The TAG of MB with persistent diastolic compression was significantly lower than the TAG without diastolic compression.

  2. Stress-induced myocardial ischemia is associated with early post-stress left ventricular mechanical dyssynchrony as assessed by phase analysis of {sup 201}Tl gated SPECT myocardial perfusion imaging

    Chen, Chien-Cheng; Shen, Thau-Yun [Show Chwan Memorial Hospital, Department of Cardiology, Changhua (China); Chang, Ming-Che [Changhua Christian Hospital, Department of Nuclear Medicine, Changhua (China); Hung, Guang-Uei [Chang Bing Show Chwan Memorial Hospital, Department of Nuclear Medicine, Changhua (China); China Medical University, Department of Biomedical Imaging and Radiological Science, Taichung (China); Chen, Wan-Chen [Chang Bing Show Chwan Memorial Hospital, Department of Nuclear Medicine, Changhua (China); Kao, Chia-Hung [China Medical University, Department of Biomedical Imaging and Radiological Science, Taichung (China); Chen, Ji [Emory University School of Medicine, Department of Radiology and Imaging Sciences, Atlanta, GA (United States)

    2012-12-15

    In {sup 201}Tl SPECT myocardial perfusion imaging (MPI) data are acquired shortly after the stress injection to assess early post-stress left ventricle (LV) function. The purpose of this study was to use {sup 201}Tl SPECT MPI to investigate whether stress-induced myocardial ischemia is associated with LV mechanical dyssynchrony. Enrolled in the study were 75 patients who were referred for dipyridamole stress and rest {sup 201}Tl gated SPECT MPI. The early post-stress scan was started 5 min after injection, and followed by the rest scan 4 h later. The patients were divided into three groups: ischemia group (N = 25, summed stress score, SSS, {>=}5, summed rest score, SRS, <5), infarct group (N = 16, SSS {>=}5, SRS {>=}5) and normal group (N = 34, SSS <5, SRS <5). LV dyssynchrony parameters were calculated by phase analysis, and compared between the stress and rest images. In the ischemia group, LV dyssynchrony was significantly larger during stress than during rest. On the contrary, LV dyssynchrony during stress was significantly smaller than during rest in the normal and infarct groups. LV dyssynchrony during rest was significantly larger in the infarct group than in the normal and ischemia groups. There were no significant differences in LV dyssynchrony during rest between the normal and ischemia groups. Stress-induced myocardial ischemia caused dyssynchronous contraction in the ischemic region, leading to a deterioration in LV synchrony. Normal myocardium had more synchronous contraction during stress. The different dyssynchrony pattern between ischemic and normal myocardium early post-stress may aid the diagnosis of coronary artery disease using {sup 201}Tl gated SPECT MPI. (orig.)

  3. Impact of right-ventricular apical pacing on the optimal left-ventricular lead positions measured by phase analysis of SPECT myocardial perfusion imaging

    Hung, Guang-Uei; Huang, Jin-Long; Lin, Wan-Yu; Tsai, Shih-Chung; Wang, Kuo-Yang; Chen, Shih-Ann; Lloyd, Michael S.; Chen, Ji

    2014-01-01

    The use of SPECT phase analysis to optimize left-ventricular (LV) lead positions for cardiac resynchronization therapy (CRT) was performed at baseline, but CRT works as simultaneous right ventricular (RV) and LV pacing. The aim of this study was to assess the impact of RV apical (RVA) pacing on optimal LV lead positions measured by SPECT phase analysis. This study prospectively enrolled 46 patients. Two SPECT myocardial perfusion scans were acquired under sinus rhythm with complete left bundle branch block and RVA pacing, respectively, following a single injection of 99m Tc-sestamibi. LV dyssynchrony parameters and optimal LV lead positions were measured by the phase analysis technique and then compared between the two scans. The LV dyssynchrony parameters were significantly larger with RVA pacing than with sinus rhythm (p ∝0.01). In 39 of the 46 patients, the optimal LV lead positions were the same between RVA pacing and sinus rhythm (kappa = 0.861). In 6 of the remaining 7 patients, the optimal LV lead positions were along the same radial direction, but RVA pacing shifted the optimal LV lead positions toward the base. The optimal LV lead positions measured by SPECT phase analysis were consistent, no matter whether the SPECT images were acquired under sinus rhythm or RVA pacing. In some patients, RVA pacing shifted the optimal LV lead positions toward the base. This study supports the use of baseline SPECT myocardial perfusion imaging to optimize LV lead positions to increase CRT efficacy. (orig.)

  4. Clinical usefulness of T1-201 myocardial scintigraphy and diastolic phase index by gated cardiac blood pool imaging in patients with hypertrophic cardiomyopathy

    Ohmine, Hiromi; Nishimura, Tsunehiko; Hayashida, Kohhei; Uehara, Toshiisa; Kozuka, Takahiro

    1984-01-01

    Tl-201 myocardial scintigraphy and gated cardiac blood pool imaging with Tc-99m were performed at rest in 24 hypertrophic cardiomyopathy (HCM) and 11 normal subjects. Based on visual analysis of Tl-201 myocardial scintigraphies, patients with HCM were subdivided into the following four groups; type I: non-obstructive, type II: obstructive, type III: asymmetric septal hypertrophy, type IV: apical hypertrophy. Characteristic myocardial hypertrophy of each group was also confirmed from the profile curves of circumferential analysis. First third filling fraction (1/3 FF) and mean first third filling rate (1/3 FRm) were obtained from gated cardiac blood pool imaging. As compaired with the normal subjects, 1/3 FF was not so sensitive for the detection of left ventricular hypertrophy. Mean+-S.D. of 1.3 FRm were 1.96+-0.56/sec (normal group), 1.30+-0.44/sec (typ e I), 1.18+-0.63/sec (type II), 1.17+-0.14/sec (type III), and 1.26+-0.03/sec (type IV). We considered that 1/3 FRm was a useful diastolic phase index in the diagnosis of HCM. (author)

  5. Myocardial perfusion SPECT imaging in patients with myocardial bridging

    Fang Wei; Qiu Hong; Yang Weixian; Wang Feng; He Zuoxiang

    2008-01-01

    Objective: Stress myocardial perfusion SPECT imaging was used to assess myocardial ischemia in patients with myocardial bridging. Methods: Ninety-six patients with myocardial bridging of the left anterior descending artery documented by coronary angiography were included in this study. All under- went exercise or pharmacological stress myocardial perfusion SPECT assessing myocardial ischemia. None had prior myocardial infarction. One year follow-up by telephone interview was performed in all patients. Results The mean stenotic severity of systolic phase on angiography was (65 ± 19)%. In the SPECT study, 20 of 96 (20.8%) patients showed abnormal perfusion. This percentage was significantly higher than that of stress electrocardiogram (ECG). The higher positive rate of SPECT perfusion images was showed in the group of patients with severe systolic narrowing (≥75%) than that with mild-to-moderate systolic narrowing (50% vs 6.3%, P<0.001). The prevalence of abnormal image was significantly higher in ELDERLY PEOPLE; patients with STT change on rest ECG than in those with normal rest ECG (54.2% vs 9.7%, P<0.001). During follow-up, one patient with abnormal SPECT perfusion image sustained angina and accepted percutaneous coronary intervention, and no cardiac event occurred in patients with normal images. Conclusions: Stress myocardial perfusion SPECT imaging can be used effectively for assessing myocardial ischemia and has potential prognostic value for patients with myocardial bridging. (authors)

  6. Cardiac functional mapping for thallium-201 myocardial perfusion, washout, wall motion and phase using single-photon emission computed tomography (SPECT)

    Nakajima, Kenichi; Bunko, Hisashi; Taniguchi, Mitsuru; Taki, Junichi; Tonami, Norihisa; Hisada, Kinichi; Hirano, Takako; Wani, Hidenobu.

    1986-01-01

    A method for three-dimensional functional mapping of Tl-201 myocardial uptake, washout, wall motion and phase was developed using SPECT. Each parameter was mapped using polar display in the same format. Normal values were determined in Tl-201 exercise study in 16 patients. Myocardial counts were lower in the septum and inferior wall and the difference of counts between anterior and inferior walls were greater in man compared with the perfusion pattern in woman. Washout was slower at septum and inferior wall in man, and slightly slower at inferior wall in woman. In gated blood-pool tomography, length-based and count-based Fourier analyses were applied to calculate the parameters of contraction and phase. The results of both Fourier analyses generally agreed; however, the area of abnormality was slightly different. Phase maps were useful for the assessment of asynergy as well as in patients with conduction disorders. These cardiac functional maps using SPECT were considered to be effective for the understanding of three-dimensional informations of cardiac function. (author)

  7. Simultaneous quantification of porcine myocardial adenine nucleotides and creatine phosphate by ion-pair reverse-phase high-performance liquid chromatography

    Cordis, G.A.; Das, D.K.

    1987-01-01

    In order to follow the energy metabolism and the levels of high-energy phosphate compounds in porcine myocardium subjected to ischemic insult, it was necessary to develop a high-performance liquid chromatography (HPLC) method where creatine phosphate (CP) and the adenine nucleotides could be measured simultaneously in a single run. Currently available ion-pair reverse-phase HPLC methods require a separate injection with a change in wavelength and mobile phase in order to measure the creatine phosphate, while baseline separation of AMP is lacking. The ion-exchange HPLC method includes a simultaneous determination, but the baseline drifts due to the gradient and baseline separation of AMP is not achieved. In the following ion-pair reverse-phase HPLC method, simultaneous measurements of porcine myocardial adenine nucleotides and creatine phosphate were achieved along with a stable baseline and homogeneous baseline separation of each measured compound, allowing accurate quantification

  8. Intracoronary administration of nicorandil during primary percutaneous coronary intervention: Impact on restoration of regional myocardial perfusion in reperfused myocardium during the subacute phase of myocardial infarction

    Wataru Takabatake

    2015-09-01

    Conclusions: 15O-labeled water PET was feasible for segmental analysis of MBF during the subacute phase of STEMI. It revealed that intracoronary administration of nicorandil to STEMI patients who underwent PCI prevented MVR elevation and thus restored MBF in the reperfused segments to a level similar to that in the normal segments.

  9. Myocardial Bridging

    Shi-Min Yuan

    2016-02-01

    Full Text Available Abstract Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with β-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

  10. Assessment of Sharp Injuries among Cameroonian Dental ...

    2010-07-10

    Jul 10, 2010 ... prophylaxis practice and methods of sharps disposal. Results ... training on guidelines adherence, safe recapping and disposal systems. Abstract ... of sharps in oral healthcare delivery and restricted nar- row field of surgery ...

  11. Analysis of sharpness increase by image noise

    Kurihara, Takehito; Aoki, Naokazu; Kobayashi, Hiroyuki

    2009-02-01

    Motivated by the reported increase in sharpness by image noise, we investigated how noise affects sharpness perception. We first used natural images of tree bark with different amounts of noise to see whether noise enhances sharpness. Although the result showed sharpness decreased as noise amount increased, some observers seemed to perceive more sharpness with increasing noise, while the others did not. We next used 1D and 2D uni-frequency patterns as stimuli in an attempt to reduce such variability in the judgment. The result showed, for higher frequency stimuli, sharpness decreased as the noise amount increased, while sharpness of the lower frequency stimuli increased at a certain noise level. From this result, we thought image noise might reduce sharpness at edges, but be able to improve sharpness of lower frequency component or texture in image. To prove this prediction, we experimented again with the natural image used in the first experiment. Stimuli were made by applying noise separately to edge or to texture part of the image. The result showed noise, when added to edge region, only decreased sharpness, whereas when added to texture, could improve sharpness. We think it is the interaction between noise and texture that sharpens image.

  12. LV dyssynchrony as assessed by phase analysis of gated SPECT myocardial perfusion imaging in patients with Wolff-Parkinson-White syndrome

    Chen, Chun; Li, Dianfu; Miao, Changqing; Zhou, Yanli; Cao, Kejiang; Feng, Jianlin; Lloyd, Michael S.; Chen, Ji

    2012-01-01

    The purpose of this study was to evaluate left ventricular (LV) mechanical dyssynchrony in patients with Wolff-Parkinson-White (WPW) syndrome pre- and post-radiofrequency catheter ablation (RFA) using phase analysis of gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). Forty-five WPW patients were enrolled and had gated SPECT MPI pre- and 2-3 days post-RFA. Electrophysiological study (EPS) was used to locate accessory pathways (APs) and categorize the patients according to the AP locations (septal, left and right free wall). Electrocardiography (ECG) was performed pre- and post-RFA to confirm successful elimination of the APs. Phase analysis of gated SPECT MPI was used to assess LV dyssynchrony pre- and post-RFA. Among the 45 patients, 3 had gating errors, and thus 42 had SPECT phase analysis. Twenty-two patients (52.4 %) had baseline LV dyssynchrony. Baseline LV dyssynchrony was more prominent in the patients with septal APs than in the patients with left or right APs (p < 0.05). RFA improved LV synchrony in the entire cohort and in the patients with septal APs (p < 0.01). Phase analysis of gated SPECT MPI demonstrated that LV mechanical dyssynchrony can be present in patients with WPW syndrome. Septal APs result in the greatest degree of LV mechanical dyssynchrony and afford the most benefit after RFA. This study supports further investigation in the relationship between electrical and mechanical activation using EPS and phase analysis of gated SPECT MPI. (orig.)

  13. LV dyssynchrony as assessed by phase analysis of gated SPECT myocardial perfusion imaging in patients with Wolff-Parkinson-White syndrome

    Chen, Chun; Li, Dianfu; Miao, Changqing; Zhou, Yanli; Cao, Kejiang [First Affiliated Hospital of Nanjing Medical University, Department of Cardiology, Nanjing, Jiangsu (China); Feng, Jianlin [First Affiliated Hospital of Nanjing Medical University, Department of Nuclear Medicine, Nanjing, Jiangsu (China); Lloyd, Michael S. [Emory University School of Medicine, Division of Cardiology, Atlanta, GA (United States); Chen, Ji [Emory University School of Medicine, Department of Radiology and Imaging Sciences, Atlanta, GA (United States)

    2012-07-15

    The purpose of this study was to evaluate left ventricular (LV) mechanical dyssynchrony in patients with Wolff-Parkinson-White (WPW) syndrome pre- and post-radiofrequency catheter ablation (RFA) using phase analysis of gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). Forty-five WPW patients were enrolled and had gated SPECT MPI pre- and 2-3 days post-RFA. Electrophysiological study (EPS) was used to locate accessory pathways (APs) and categorize the patients according to the AP locations (septal, left and right free wall). Electrocardiography (ECG) was performed pre- and post-RFA to confirm successful elimination of the APs. Phase analysis of gated SPECT MPI was used to assess LV dyssynchrony pre- and post-RFA. Among the 45 patients, 3 had gating errors, and thus 42 had SPECT phase analysis. Twenty-two patients (52.4 %) had baseline LV dyssynchrony. Baseline LV dyssynchrony was more prominent in the patients with septal APs than in the patients with left or right APs (p < 0.05). RFA improved LV synchrony in the entire cohort and in the patients with septal APs (p < 0.01). Phase analysis of gated SPECT MPI demonstrated that LV mechanical dyssynchrony can be present in patients with WPW syndrome. Septal APs result in the greatest degree of LV mechanical dyssynchrony and afford the most benefit after RFA. This study supports further investigation in the relationship between electrical and mechanical activation using EPS and phase analysis of gated SPECT MPI. (orig.)

  14. NASA-Ames Summer High School Apprenticeship Research Program (SHARP)

    Powell, P.

    1983-01-01

    The function of SHARP is to recognize high school juniors who have demonstrated unusually high promise for sucess in mathemtics and science. Twenty academically talented students who will be seniors in high school in September were chosen to participate in SHARP 83. Mentors were selected to provide students with first-hand experiences in a research and development environment in order that each student might try out his or her tentative professional career choice. Some special features of SHARP included field trips to private industries doing similar and related research, special lectures on topics of research here at ARC, individual and group counseling sessions, written research papers and oral reports, and primarily the opportunity to be exposed to the present frontiers in space exploration and research. The long-range goal of SHARP is to contribute to the future recruitment of needed scientists and engineers. This final report is summary of all the phases of the planning and implemenation of the 1983 Summer High School Apprenticeship Research Program (SHARP).

  15. Myocardial infarction

    Ando, Jyoji; Yasuda, Hisakazu; Miyamoto, Atsushi; Kobayashi, Tsuyoshi

    1980-01-01

    sup(99m)Tc-pyrophosphate (PYP) scintigraphy and 201 Tl myocardial scintigraphy were utilized for the diagnoses of the presence, the region, and the extent of myocardial infarction. Exercise 201 Tl myocardial scintigrams and exercise radionuclide ventriculography were utilized for diagnosis of coronary artery lesions in angina pectoris. Radionuclide ventriculography was used to investigate effects of coronary artery lesions on cardiac function and hemodynamics. In order to select adequate treatments for myocardial infarction and estimate the prognosis, it was necessary to detect the presence, the region, and the extent of acute myocardial infarction and to investigate effects of partial infarction on hemodynamics by using radionuclide imaging. Exercise myocardial scintigraphy could be carried out noninvasively and repeatedly for diagnosis of coronal artery disease. Therefore, this method could be applied widely. It was possible to use this method as a screening test of coronary artery diseases for the diagnoses of asymptomatic patients who showed ST changes in ECG, the patients with cardiac neurosis and the patency after a reconstructive surgery of coronary artery. (Tsunoda, M.)

  16. LV dyssynchrony as assessed by phase analysis of gated SPECT myocardial perfusion imaging in patients with Wolff-Parkinson-White syndrome.

    Chen, Chun; Li, Dianfu; Miao, Changqing; Feng, Jianlin; Zhou, Yanli; Cao, Kejiang; Lloyd, Michael S; Chen, Ji

    2012-07-01

    The purpose of this study was to evaluate left ventricular (LV) mechanical dyssynchrony in patients with Wolff-Parkinson-White (WPW) syndrome pre- and post-radiofrequency catheter ablation (RFA) using phase analysis of gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). Forty-five WPW patients were enrolled and had gated SPECT MPI pre- and 2-3 days post-RFA. Electrophysiological study (EPS) was used to locate accessory pathways (APs) and categorize the patients according to the AP locations (septal, left and right free wall). Electrocardiography (ECG) was performed pre- and post-RFA to confirm successful elimination of the APs. Phase analysis of gated SPECT MPI was used to assess LV dyssynchrony pre- and post-RFA. Among the 45 patients, 3 had gating errors, and thus 42 had SPECT phase analysis. Twenty-two patients (52.4%) had baseline LV dyssynchrony. Baseline LV dyssynchrony was more prominent in the patients with septal APs than in the patients with left or right APs (p syndrome. Septal APs result in the greatest degree of LV mechanical dyssynchrony and afford the most benefit after RFA. This study supports further investigation in the relationship between electrical and mechanical activation using EPS and phase analysis of gated SPECT MPI.

  17. Assessment of sharps waste management practices in a referral ...

    hospital (40.8 kg/day) was higher than values reported in district hospitals, but the sharps waste ... Key words: Sharps waste, sharps waste container, overfilled safety box, sharps waste proportion, .... requirements and availability of technology.

  18. Myocardial scintigraphy

    Bunko, Hisashi; Hisada, Kinichi

    1982-01-01

    Among the various methods of image diagnosis of the cardiovascular disorder, nuclear cardiology provides noninvasive means for evaluation of myocardial perfusion as well as morphological and functional informations. In this article, clinical application and image diagnosis of myocardial scintigraphy including Tl-201 myocardial perfusion scintigraphy, single photon emission computed tomography with Tl-201, acute myocardial infarction scintigraphy with Tc-99m-pyrophosphate and Ga-67 imaging of the heart, were discussed. Multiplanar imaging of the heart with Tl-201 after stress and at redistribution was the accepted method for detection and evaluation of the ischemic heart disease. Although it achieved high sensitivity and specificity for ischemic heart disease, detection of the small ischemia and quantation of the regional Tl-201 accumulation were difficult with conventional multiplanar imaging. Application of emission computed tomography improved detectability and quantitativity of the ischemia. However, 7-pinhole tomography did not increase the diagnostic accuracy significantly. It had limited clinical applicability due to poor quantitativity in spite of improved image contrast and its tomographic nature. Advantage and limitation of these tomographic imaging and multiplanar imaging were discussed. Problems and prognostic significance of pyrophosphate imaging of the acute myocardial infarction were also discussed. Visualization of the heart with Ga-67 was helpful for identification of the tumor or inflammation of the heart as well as evaluation of the effect of the therapy. (author)

  19. Difference in myocardial flow reserve between patients with dilated cardiomyopathy and those with dilated phase of hypertrophic cardiomyopathy. Evaluation by 15O-water PET

    Ohba, Muneo; Kambara, Naoshige; Hosokawa, Ryohei

    2007-01-01

    The clinical features of patients with the dilated phase of hypertrophic cardiomyopathy (DHCM) may resemble those of patients with dilated cardiomyopathy (DCM); that is, systolic dysfunction and left ventricular dilatation. Myocardial flow reserve (MFR) is impaired in patients with nonischemic cardiomyopathy, and the reduced MFR may be related to poor prognosis. Several studies report that the mortality rate for patients with DHCM is higher than for DCM, but the difference between these 2 cardiomyopathies is still unclear. The purpose of this study was to assess the MFR of these 2 cardiomyopathies, using 15 O-water positron emission tomography (PET) to elucidate their differences. In total 30 patients were investigated: 23 with DCM (Group A) and 7 with DHCM (Group B). All those who were in a stable condition underwent cardiac catheterization. Myocardial blood flow (MBF) at rest and under adenosine 5'-triphosphate (ATP) infusion was measured by 15 O-water PET, and the MFR was calculated. There were no significant differences in the hemodynamics of the 2 groups. The mean MFR in DHCM was significantly lower than that in DCM (1.49±0.31 vs 2.62±1.08; p=0.042), whereas MBF at rest did not differ (DCM vs DHCM: 0.66±0.20 vs 0.49±0.05 ml·min -1 ·g -1 ; no significance (NS)). The MFR in both Group A and B was significantly decreased compared with the normal controls (MFR in normal controls: 5.15±1.64, p=0.00015, 0.00013, respectively). These results suggest that impaired vasodilatation (ie, dysfunction of the microcirculation) is more severe in patients with DHCM than in patients with DCM, even though patients' characteristics and hemodynamics do not differ. (author)

  20. Difference in the Clinical Characteristics of Ventricular Fibrillation Occurrence in the Early Phase of an Acute Myocardial Infarction Between Patients With and Without J Waves.

    Naruse, Yoshihisa; Nogami, Akihiko; Harimura, Yoshie; Ishibashi, Mayu; Noguchi, Yuichi; Sekiguchi, Yukio; Sato, Akira; Aonuma, Kazutaka

    2015-08-01

    We recently showed that the presence of J waves increases the risk of ventricular fibrillation (VF) occurrence in the early phase of an acute myocardial infarction (AMI). This study aimed to evaluate the clinical characteristics of VF occurrences in the early phase of an AMI between patients with and without J waves. This retrospective, observational study included 281 consecutive patients with an AMI (69 ± 12 years; 207 men) in whom 12-lead ECGs before AMI onset could be evaluated. The patients were classified based on a VF occurrence J waves. J waves were electrocardiographically defined as an elevation of the terminal portion of the QRS complex of >0.1 mV from baseline in at least 2 contiguous inferior or lateral leads. VF occurred in 24 patients, and J waves were present in 37. VF occurrence was more prevalent in the patients with than without J waves (27% vs. 6%; P J waves, peak creatine kinase level (P J waves, there was no significant difference in these variables. There was no association between the location of J waves and the infarct area. In patients with AMI, those with J waves were more likely to develop VF and less likely to have high-risk clinical characteristics than those without J waves. © 2015 Wiley Periodicals, Inc.

  1. Summer High School Apprenticeship Research Program (SHARP)

    1997-01-01

    The summer of 1997 will not only be noted by NASA for the mission to Mars by the Pathfinder but also for the 179 brilliant apprentices that participated in the SHARP Program. Apprentice participation increased 17% over last year's total of 153 participants. As indicated by the End-of-the-Program Evaluations, 96% of the programs' participants rated the summer experience from very good to excellent. The SHARP Management Team began the year by meeting in Cocoa Beach, Florida for the annual SHARP Planning Conference. Participants strengthened their Education Division Computer Aided Tracking System (EDCATS) skills, toured the world-renowned Kennedy Space Center, and took a journey into space during the Alien Encounter Exercise. The participants returned to their Centers with the same goals and objectives in mind. The 1997 SHARP Program goals were: (1) Utilize NASA's mission, unique facilities and specialized workforce to provide exposure, education, and enrichment experiences to expand participants' career horizons and inspire excellence in formal education and lifelong learning. (2) Develop and implement innovative education reform initiatives which support NASA's Education Strategic Plan and national education goals. (3) Utilize established statistical indicators to measure the effectiveness of SHARP's program goals. (4) Explore new recruiting methods which target the student population for which SHARP was specifically designed. (5) Increase the number of participants in the program. All of the SHARP Coordinators reported that the goals and objectives for the overall program as well as their individual program goals were achieved. Some of the goals and objectives for the Centers were: (1) To increase the students' awareness of science, mathematics, engineering, and computer technology; (2) To provide students with the opportunity to broaden their career objectives; and (3) To expose students to a variety of enrichment activities. Most of the Center goals and

  2. Knowledge Base Editor (SharpKBE)

    Tikidjian, Raffi; James, Mark; Mackey, Ryan

    2007-01-01

    The SharpKBE software provides a graphical user interface environment for domain experts to build and manage knowledge base systems. Knowledge bases can be exported/translated to various target languages automatically, including customizable target languages.

  3. Phase analysis for the assessment of left ventricular dyssynchrony by Gated Myocardial Perfusion SPECT. Importance of clinical and technical parameters

    Víctor Marín-Oyaga

    2017-07-01

    Conclusions: The new PA tool of nuclear medicine is feasible in our context. The type of stress, the administered dose, the study phase or the gamma camera used did not affect the parameters. However, gender, interventricular conduction disorders, necrosis and systolic dysfunction did have an impact on them.

  4. A note on trader Sharpe Ratios.

    Coates, John M; Page, Lionel

    2009-11-25

    Traders in the financial world are assessed by the amount of money they make and, increasingly, by the amount of money they make per unit of risk taken, a measure known as the Sharpe Ratio. Little is known about the average Sharpe Ratio among traders, but the Efficient Market Hypothesis suggests that traders, like asset managers, should not outperform the broad market. Here we report the findings of a study conducted in the City of London which shows that a population of experienced traders attain Sharpe Ratios significantly higher than the broad market. To explain this anomaly we examine a surrogate marker of prenatal androgen exposure, the second-to-fourth finger length ratio (2D:4D), which has previously been identified as predicting a trader's long term profitability. We find that it predicts the amount of risk taken by traders but not their Sharpe Ratios. We do, however, find that the traders' Sharpe Ratios increase markedly with the number of years they have traded, a result suggesting that learning plays a role in increasing the returns of traders. Our findings present anomalous data for the Efficient Markets Hypothesis.

  5. A note on trader Sharpe Ratios.

    John M Coates

    Full Text Available Traders in the financial world are assessed by the amount of money they make and, increasingly, by the amount of money they make per unit of risk taken, a measure known as the Sharpe Ratio. Little is known about the average Sharpe Ratio among traders, but the Efficient Market Hypothesis suggests that traders, like asset managers, should not outperform the broad market. Here we report the findings of a study conducted in the City of London which shows that a population of experienced traders attain Sharpe Ratios significantly higher than the broad market. To explain this anomaly we examine a surrogate marker of prenatal androgen exposure, the second-to-fourth finger length ratio (2D:4D, which has previously been identified as predicting a trader's long term profitability. We find that it predicts the amount of risk taken by traders but not their Sharpe Ratios. We do, however, find that the traders' Sharpe Ratios increase markedly with the number of years they have traded, a result suggesting that learning plays a role in increasing the returns of traders. Our findings present anomalous data for the Efficient Markets Hypothesis.

  6. The Sharp Lepton Quandary: Reasonable cautions

    Griffin, J.J.

    1996-02-01

    Surprisingly, the new APEX experiment designed to measure a definitive invariant mass distribution of the sharp pairs previously reported in similar heavy ion studies reports null results. Although it asserts no direct conflict with any data reported by EPOS/I, the APEX report nevertheless seems to have encouraged the view that the earlier (EPOS/I) observations were erroneous, and by extrapolation, that the whole (e + e - ) Puzzle data set can be dismissed as an unfortunate set of physically meaningless statistical fluctuations. We wish here to argue that such sweeping judgments should be postponed, on the grounds that (1) the published APEX analysis of their data is self-inconsistent, and can therefore sustain no valid inference about the EPOS/I data; (2) the data which supports the occurrence of sharp (e + e - ) pairs is much more extensive than the EPOS/I data, so that the APEX surprise must be considered as one episode in a much longer struggle finally to settle the question of whether these weak signals are significant or not; (3) a qualitative phenomenology exists which can organize the whole range of data of the Sharp Lepton Problem, and which suggests that (4) certain low energy (and low cost) experiments ought to be explored for their creation of sharp pairs; as follows: the study of pairs emitted following scattering of few MeV electron and positron beams from neutral U and Th atoms, and the study of pairs emitted following the resonant absorption of photons of 1.5 to 2.0 MeV on U and Th atoms. We first present a brief data-oriented history of the Sharp Lepton Problem, to show that no single unexpected null result can provide an adequate basis for rejecting the great range and quantity of data which evidences the occurrence of sharp pairs. We then consider the Quadronium Composite Particle Scenario for these processes, and its Quantum Electrodynamical implications, in support of the above recommendations

  7. Evaluating the normal individual cardiac function in different imaging phases post exercise and rest by gated SPECT myocardial perfusion

    Hua, W.; Li, S.J.; Liu, J.Z.; Li, X.F.; Jin, C.R.; Hu, G.; Wang, J.

    2007-01-01

    Full text: Objectives: To evaluate the normal individual cardiac function in the different imaging phases post-exercise and rest by GSPECT. Methods: 46 normal individuals underwent exercise/rest GSPECT using 99mTc-MIBI by 2- day program. Sequential imaging was started 15, 35 and 120 minutes after exercise and rest imaging was performed the following day. The left ventricular EF and EDV, ESV values were calculated with the Cedars-Sinai program. Results: The EF values of post- exercise at 15, 35, and 120m was 64.48±7.43%, 65.02±7.66%, and 60.98±7.28% respectively, and the rest EF value was 61.46±7.23%. The post exercise EF at 15m and 35m was higher than EF at post- exercise 120m and rest, but there is a significant difference only between post exercise 35m and rest (P< 0.05), and all post exercise EF did not increase at least 5% from EF at-rest. The EDV and ESV values did not have statistically significant differences at 15, 35,120m post-exercise and rest. The heart rate at 15,35m post- exercise was higher significantly than at rest. Conclusions: The different imaging phases after exercise with 99mTc-MIBI GSPECT affects LVEF in normal individuals, the 35m post- exercise EF is highest. (author)

  8. Acoustic streaming of a sharp edge.

    Ovchinnikov, Mikhail; Zhou, Jianbo; Yalamanchili, Satish

    2014-07-01

    Anomalous acoustic streaming is observed emanating from sharp edges of solid bodies that are vibrating in fluids. The streaming velocities can be orders of magnitude higher than expected from the Rayleigh streaming at similar amplitudes of vibration. Acoustic velocity of fluid relative to a solid body diverges at a sharp edge, giving rise to a localized time-independent body force acting on the fluid. This force results in a formation of a localized jet. Two-dimensional numerical simulations are performed to predict acoustic streaming for low amplitude vibration using two methods: (1) Steady-state solution utilizing perturbation theory and (2) direct transient solution of the Navier-Stokes equations. Both analyses agree with each other and correctly predict the streaming of a sharp-edged vibrating blade measured experimentally. The origin of the streaming can be attributed to the centrifugal force of the acoustic fluid flow around a sharp edge. The dependence of this acoustic streaming on frequency and velocity is examined using dimensional analysis. The dependence law is devised and confirmed by numerical simulations.

  9. SHARP {Summer High School Apprenticeship Research Program}

    Glasco, Deborah (Technical Monitor)

    2002-01-01

    The Year 2002 was another successful year for SHARP. Even after 22 years of SHARP, the Program continues to grow. There were 12 NASA Field Installations with a total of 210 apprentices who participated in the summer 2002 Program supported by 215 mentors in the fields of science and engineering. The apprentices were chosen from a pool of 1,379 applicants. This was a record year for applications exceeding the previous year by over 60%. For the second consecutive year, the number of female participants exceeded the number of males with 53% female and 47% male participants in the program. The main thrust of our recruiting efforts is still focused on underrepresented populations; especially African American, Hispanic, and Native American. At the conclusion of the summer program, most SHARP Apprentices indicated on the EDCATS that they would be interested in pursuing careers in Aerospace (56.2%) while the second largest career choice was a job at NASA (45.7%). The smallest number (11.9%) were interested in careers in the government. The table of responses is listed in the Appendix. Once again this year we were fortunate in that the SHARP COTR, Ms. Deborah Glasco, gained the support of MURED funding sources at NASA to fully fund additional apprentices and boost the number of apprentices to 210.

  10. Thallium-201 myocardial imaging in acute-myocardial infarction

    Wackers, F.J.Th.; Lie, K.I.; Sokole, E.B.; Wellens, H.J.J.; Samson, G.; Schoot, J.B. van der

    1980-01-01

    Thallium-201 scintigraphy has proven to be an early and highly sensitive technique to detect myocardial perfusion abnormalities in patients with acute myocardial infarction. During the early phase of acute myocardial infarction, patients may be hemodynamically and electrically unstable. Therefore, scintigraphy is performed preferably at the bed side in the Coronary Care Unit using a mobile gamma camera. Additionally, in order to shorten imaging time in these often critically ill patients, the authors recommend injecting no less than 2 mCi of 201 Tl. Using this dosage, the imaging time per view will be approximately five minutes. Routinely, three views are taken: the first view is a supine 45 0 left-anterior-oblique view, followed by a supine anterior view and finally a left-lateral view, the latter with the patient turned on the right side. (Auth.)

  11. End-point sharpness in thermometric titrimetry.

    Tyrrell, H J

    1967-07-01

    It is shown that the sharpness of an end-point in a thermometric titration where the simple reaction A + B right harpoon over left harpoon AB takes place, depends on Kc(A') where K is the equilibrium constant for the reaction, and c(A') is the total concentration of the titrand (A) in the reaction mixture. The end-point is sharp if, (i) the enthalpy change in the reaction is not negligible, and (ii) Kc(A') > 10(3). This shows that it should, for example, be possible to titrate 0.1 M acid, pK(A) = 10, using a thennometric end-point. Some aspects of thermometric titrimetry when Kc(A') < 10(3) are also considered.

  12. Myocardial scintigraphy with thallium-201

    Schwaiger, M.; Silber, S.; Klein, U.; Rudolph, W.

    1980-01-01

    Thallium-201 myocardial scintigraphy is an important non-invasive method for assessment of coronary artery disease. Other applications of the method such as delineation of the right ventricular free wall in right ventricular overload, or the detection of hypertrophic cardiomyopathies or myocardial infiltrations are of subordinate importance. In heart disease such as congestive cardiomyopathy and mitral valve prolapse thallium-201 uptake defects have been described, the clinical implications of these findings, however, cannot be adequately interpreted at this time. Myocardial uptake of thallium-201 is an active process, dependent on and proportional to perfusion. Differentiation between myocardial ischemia and myocardial scar is based on the presence or absence of thallium-201 'redistribution'. That is, in the presence of acute reversible ischemia there is increased thallium-201 uptake in the post-ischemic phase in previously hypoperfused myocardium and, subsequently, equilibrium of the initially registered activity differences. 'Redistribution' has also been described in the resting scintigram of patients with severe coronary artery disease and chronic hypoperfusion. (orig.) [de

  13. Sharp inequalities for tangent function with applications

    Hui-Lin Lv

    2017-05-01

    Full Text Available Abstract In the article, we present new bounds for the function e t cot ( t − 1 $e^{t\\cot(t-1}$ on the interval ( 0 , π / 2 $(0, \\pi/2$ and find sharp estimations for the Sine integral and the Catalan constant based on a new monotonicity criterion for the quotient of power series, which refine the Redheffer and Becker-Stark type inequalities for tangent function.

  14. The stratigraphy and evolution of lower Mount Sharp from spectral, morphological, and thermophysical orbital data sets.

    Fraeman, A A; Ehlmann, B L; Arvidson, R E; Edwards, C S; Grotzinger, J P; Milliken, R E; Quinn, D P; Rice, M S

    2016-09-01

    We have developed a refined geologic map and stratigraphy for lower Mount Sharp using coordinated analyses of new spectral, thermophysical, and morphologic orbital data products. The Mount Sharp group consists of seven relatively planar units delineated by differences in texture, mineralogy, and thermophysical properties. These units are (1-3) three spatially adjacent units in the Murray formation which contain a variety of secondary phases and are distinguishable by thermal inertia and albedo differences, (4) a phyllosilicate-bearing unit, (5) a hematite-capped ridge unit, (6) a unit associated with material having a strongly sloped spectral signature at visible near-infrared wavelengths, and (7) a layered sulfate unit. The Siccar Point group consists of the Stimson formation and two additional units that unconformably overlie the Mount Sharp group. All Siccar Point group units are distinguished by higher thermal inertia values and record a period of substantial deposition and exhumation that followed the deposition and exhumation of the Mount Sharp group. Several spatially extensive silica deposits associated with veins and fractures show that late-stage silica enrichment within lower Mount Sharp was pervasive. At least two laterally extensive hematitic deposits are present at different stratigraphic intervals, and both are geometrically conformable with lower Mount Sharp strata. The occurrence of hematite at multiple stratigraphic horizons suggests redox interfaces were widespread in space and/or in time, and future measurements by the Mars Science Laboratory Curiosity rover will provide further insights into the depositional settings of these and other mineral phases.

  15. [Effectiveness of combined use of kontrykal and nitroglycerin in the acute period of myocardial infarction].

    Lazutin, V K; Broun, D K; Barashkov, M I; Kuparev, I I; Kibalova, G A; Samorukova, N T; Zapevalov, M V

    1990-04-01

    The natural history and extension of myocardial infarction were studied from parameters of precordial ECG in 35 leads and central hemodynamic findings in 100 patients with acute myocardial infarction. The least extension of myocardial lesion areas and better central hemodynamic parameters and a sharp reduction in the frequency of complications and hospital mortality in patients receiving a combined therapy with contrykal and nitroglycerin as a continuous long-term infusion within the first 24 hours of myocardial infarction as compared with the controls and in those having these agents alone.

  16. Long Term Effects of Percutaneous Coronary Intervention of the Totally Occluded Infarct-Related Artery in the Subacute Phase after Myocardial Infarction

    Hochman, Judith S; Reynolds, Harmony R; Džavík, Vladimír; Buller, Christopher E; Ruzyllo, Witold; Sadowski, Zygmunt P; Maggioni, Aldo P; Carvalho, Antonio C; Rankin, James M.; White, Harvey D.; Goldberg, Suzanne; Forman, Sandra A; Mark, Daniel B; Lamas, Gervasio A

    2011-01-01

    Background Despite observations suggesting a benefit for late opening of occluded infarct-related arteries (IRA) post-myocardial infarction (MI), the Occluded Artery Trial (OAT) demonstrated no reduction in the composite of death, reinfarction and class IV heart failure (HF) over 2.9-yearmean follow-up. Follow-up was extended to determine whether late trends would favor either treatment group. Methods and Results OAT randomized 2201 stable patients with IRA occlusion >24hours (calendar days3-28) after MI. Severe inducible ischemia, rest angina, class III-IV HF and 3-vessel/left main disease were excluded. We conducted extended followed up of enrolled patients for an additional 3 years for the primary endpoint and angina (6-year median survivor follow up, longest 9 years, 12,234 patient-years).Rates of the primary endpoint (HR 1.06, 95% CI 0.88-1.28), fatal and nonfatal MI (HR 1.25, 95% CI 0.89-1.75), death and class IV HF were similar for PCI vs. MED groups. No interaction between baseline characteristics and treatment group on outcomes were observed. The vast majority of patients at each follow-up visit did not report angina. There was less angina in the PCI group through early in follow-up; by 3 years the between group difference was consistently <4 patients per 100 treated and not significantly different though there was a trend toward less angina in the PCI group at 3 and 5 years. The 7-year rate of PCI of the IRA during follow up was 11.1% for the PCI group compared to 14.7% for the MED group (HR 0.79, 95% CI 0.61-1.01. p=0.06). Conclusions Extended follow up of the OAT cohort provides robust evidence for no reduction of long-term rates of clinical events after routine PCI in stable patients with an occluded IRA and without severe inducible ischemia in the subacute phase post-MI. PMID:22025606

  17. Combination of Evidence-Based Medical Therapy in Acute Phase of Non-ST-Elevation Myocardial Infarction and Reduction of In-Hospital Mortality

    Monhart, Z.; Grünfeldová, H.; Zvárová, Jana; Janský, P.

    2010-01-01

    Roč. 122, č. 2 (2010), e244 ISSN 0009-7322. [World Congress of Cardiology . 16.06.2010-19.06.2010, Beijing] Institutional research plan: CEZ:AV0Z10300504 Keywords : cardioloy * myocardial infarction * in-hospital mortality Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  18. Myocardial protection in heart surgery.

    Mentzer, Robert M

    2011-01-01

    One of the unmet clinical needs in heart surgery is the prevention of myocardial stunning and necrosis that occurs as a result of ischemia-reperfusion. Myocardial stunning, a frequent consequence after heart surgery, is characterized by a requirement for postoperative inotropic support despite a technically satisfactory heart operation. In high-risk patients with marginal cardiac reserve, stunning is a major cause of prolonged critical care and may be associated with as much as a 5-fold increase in mortality. In contrast, the frequency of myocardial necrosis (myocardial infarction [MI]) after cardiac surgery is less appreciated and its consequences are much more subtle. The consequences may not be apparent for months to years. While we now have a much better understanding of the molecular mechanisms underlying myocardial stunning and MI, we still have no effective way to prevent these complications, nor a consistently effective means to engage the well-studied endogenous mechanisms of cardioprotection. The failure to develop clinically effective interventions is multifactorial and can be attributed to reliance on findings obtained from subcellular and cellular studies, to drawing conclusions from preclinical large animal studies that have been conducted in a disease-free state, and to accepting less than robust surrogate markers of injury in phase II clinical trials. These factors also explain the disappointing failure to identify effective adjuvant therapy in the setting of percutaneous coronary revascularization for acute MI (AMI) and reperfusion injury. These issues have contributed to the disappointing outcomes of large and costly phase III trials, resulting in a lack of enthusiasm on the part of the pharmaceutical industry to engage in further drug development for this indication. The purpose of this review is to (1) define the scope of the clinical problem; (2) summarize the outcomes of selected phases II and III clinical trials; and (3) identify the gap that

  19. Myocardial perfusion in silent myocardial ischemia

    Narita, Michihiro; Kurihara, Tadashi; Murano, Kenichi; Usami, Masahisa

    1989-01-01

    To investigate myocardial perfusion in silent myocardial ischemia, we performed exercise stress myocardial tomography with thallium-201 (Tl) in 85 patients with coronary artery disease (CAD). Exercise stress myocardial tomography was obtained both immediately after exercise and three hours later. Patients were classified into two groups according to the presence (Symptomatic Group, n=36) or absence (Silent Group, n=49) of chest pain during exercise stress. Clinical features (age, gender and history of myocardial infarction) and arteriographically determined severity of CAD were the same in both groups. The extent of myocardial ischemia (% Ischemia) estimated by exercise stress myocardial tomography was the same in each group (30±10 % in Silent Group, 28±12 % in Symptomatic Group, NS). The severity of exercise-induced myocardial ischemia was expressed as a minimal value of myocardial Tl washout rate (minimal WOR) of each patient. Although exercise heart rate was identical in both groups, minimal WOR in Silent Group was significantly higher than that of Symptomatic Group (4±10% vs -16±14%, p<0.001). The study in patients who exhibited both silent and symptomatic ischemia showed the same results. These findings suggest that the severity of ischemia is a fundamental factor in determining the presence or absence of pain during exercise induced ischemia. (author)

  20. Flow Control Over Sharp-Edged Wings

    2007-07-01

    Gad-el-Hak (2001) as the ability to actively or passively manipulate a flow field to effect a desired change. The challenge is to achieve that change...combinations. Been able to independently control both is a great challenge . These requirements may appear too stringent for the sharp- edged airfoils...06 0𔄁 08 09 lic Vlc Figure 22: Pressure distributions for Model B at a=13 °. Stations I (left); 2 (right) 1 , -2 1 F - [12 1 -6a -16 08 -08 06 -06

  1. Sharp fronts within geochemical transport problems

    Grindrod, P.

    1995-01-01

    The authors consider some reactive geochemical transport problems in groundwater systems. When incoming fluid is in disequilibrium with the mineralogy sharp transition fronts may develop. They show that this is a generic property for a class of systems where the timescales associated with reaction and diffusion phenomena are much shorter than those associated with advective transport. Such multiple timescale problems are relevant to a variety of processes in natural systems: mathematically methods of singular perturbation theory reduce the dimension of the problems to be solved locally. Furthermore, they consider how spatial heterogeneous mineralogy can impact upon the propagation of sharp geochemical fronts. The authors developed an asymptotic approach in which they solve equations for the evolving geometry of the front and indicate how the non-smooth perturbations due to natural heterogeneity of the mineralogy on underlying ground water flow field are balanced against the smoothing effect of diffusion/dispersive processes. Fronts are curvature damped, and the results here indicate the generic nature of separate front propagation within both model (idealized) and natural (heterogeneous) geochemical systems

  2. Status report on SHARP coupling framework.

    Caceres, A.; Tautges, T. J.; Lottes, J.; Fischer, P.; Rabiti, C.; Smith, M. A.; Siegel, A.; Yang, W. S.; Palmiotti, G.

    2008-05-30

    This report presents the software engineering effort under way at ANL towards a comprehensive integrated computational framework (SHARP) for high fidelity simulations of sodium cooled fast reactors. The primary objective of this framework is to provide accurate and flexible analysis tools to nuclear reactor designers by simulating multiphysics phenomena happening in complex reactor geometries. Ideally, the coupling among different physics modules (such as neutronics, thermal-hydraulics, and structural mechanics) needs to be tight to preserve the accuracy achieved in each module. However, fast reactor cores in steady state mode represent a special case where weak coupling between neutronics and thermal-hydraulics is usually adequate. Our framework design allows for both options. Another requirement for SHARP framework has been to implement various coupling algorithms that are parallel and scalable to large scale since nuclear reactor core simulations are among the most memory and computationally intensive, requiring the use of leadership-class petascale platforms. This report details our progress toward achieving these goals. Specifically, we demonstrate coupling independently developed parallel codes in a manner that does not compromise performance or portability, while minimizing the impact on individual developers. This year, our focus has been on developing a lightweight and loosely coupled framework targeted at UNIC (our neutronics code) and Nek (our thermal hydraulics code). However, the framework design is not limited to just using these two codes.

  3. The Spectral Sharpness Angle of Gamma-ray Bursts

    Hendrik J. van Eerten

    2016-06-01

    Full Text Available We extend the results of Yu et al. (2015b of the novel sharpness angle measurement to a large number of spectra obtained from the Fermi gamma-ray burst monitor. The sharpness angle is compared to the values obtained from various representative emission models: blackbody, single-electron synchrotron, synchrotron emission from a Maxwellian or power-law electron distribution. It is found that more than 91% of the high temporally and spectrally resolved spectra are inconsistent with any kind of optically thin synchrotron emission model alone. It is also found that the limiting case, a single temperature Maxwellian synchrotron function, can only contribute up to 58+23 -18% of the peak flux. These results show that even the sharpest but non-realistic case, the single-electron synchrotron function, cannot explain a large fraction of the observed spectra. Since any combination of physically possible synchrotron spectra added together will always further broaden the spectrum, emission mechanisms other than optically thin synchrotron radiation are likely required in a full explanation of the spectral peaks or breaks of the GRB prompt emission phase.

  4. Sharp superconductor-insulator transition in short wires

    Meidan, Dganit; Oreg, Yuval; Refael, Gil; Smith, Robert A.

    2008-01-01

    Recent experiments on short MoGe nanowires show a sharp superconductor-insulator transition tuned by the normal state resistance of the wire, with a critical resistance of R c ∼ R Q = h/(4e 2 ). These results are at odds with a broad range of theoretical work on Josephson-like systems that predicts a smooth transition, tuned by the value of the resistance that shunts the junction. We develop a self-consistent renormalization group treatment of interacting phase-slips and their dual counterparts, correlated cooper pair tunneling, beyond the dilute approximation. This analysis leads to a very sharp transition with a critical resistance of R Q . The addition of the quasi-particles' resistance at finite temperature leads to a quantitative agreement with the experimental results. This self-consistent renormalization group method should also be applicable to other physical systems that can be mapped onto similar sine-Gordon models, in the previously inaccessible intermediate-coupling regime

  5. Classification of myocardial infarction

    Saaby, Lotte; Poulsen, Tina Svenstrup; Hosbond, Susanne Elisabeth

    2013-01-01

    The classification of myocardial infarction into 5 types was introduced in 2007 as an important component of the universal definition. In contrast to the plaque rupture-related type 1 myocardial infarction, type 2 myocardial infarction is considered to be caused by an imbalance between demand...

  6. 77 FR 56647 - Lisa Jean Sharp: Debarment Order

    2012-09-13

    ... Act (the FD&C Act) permanently debarring Lisa Jean Sharp from providing services in any capacity to a...&C Act. Ms. Sharp was given notice of the proposed permanent debarment and an opportunity to request... drug product under the FD&C Act. The factual basis for this conviction is as follows: Ms. Sharp was the...

  7. Sharp corners as sources of spiral pairs

    Biton, Y.; Rabinovitch, A.; Braunstein, D.; Friedman, M.; Aviram, I.

    2010-01-01

    It is demonstrated that using the FitzHugh-Nagumo model, stimulation of excitable media inside a region possessing sharp corners, can lead to the appearance of sources of spiral-pairs of sustained activity. The two conditions for such source creation are: The corners should be less than 120 deg. and the range of stimulating amplitudes should be small, occurring just above the threshold value and decreasing with the corner angle. The basic mechanisms driving the phenomenon are discussed. These include: A. If the corner angle is below 120 deg., the wave generated inside cannot emerge at the corner tip, resulting in the creation of two free edges which start spiraling towards each other. B. Spiraling must be strong enough; otherwise annihilation of the rotating arms would occur too soon to create a viable source. C. The intricacies of the different radii involved are elucidated. Possible applications in heart stimulation and in chemical reactions are considered.

  8. Sharp estimates for damped oscillatory integrals

    Ikromov, I.A.; Shaimardanov, S.S.

    2004-05-01

    We consider a real-analytic hypersurface S in R 3 with surface measure dS, ψ is a smooth function with compact support, and we let dμ α be the surface measure with dμ α = ψ vertical bar K(x) vertical bar α dS, where K(x) is the Gaussian curvature of the surface. We show that if S is a real analytic hypersurface with one non-vanishing principal curvature and α > 1, then μ-circumflex α (ξ) decays as O (vertical bar ξ vertical bar -1 ). The well-known examples show that the estimate for the exponent α is sharp. (author)

  9. SHARP ENTRYWISE PERTURBATION BOUNDS FOR MARKOV CHAINS.

    Thiede, Erik; VAN Koten, Brian; Weare, Jonathan

    For many Markov chains of practical interest, the invariant distribution is extremely sensitive to perturbations of some entries of the transition matrix, but insensitive to others; we give an example of such a chain, motivated by a problem in computational statistical physics. We have derived perturbation bounds on the relative error of the invariant distribution that reveal these variations in sensitivity. Our bounds are sharp, we do not impose any structural assumptions on the transition matrix or on the perturbation, and computing the bounds has the same complexity as computing the invariant distribution or computing other bounds in the literature. Moreover, our bounds have a simple interpretation in terms of hitting times, which can be used to draw intuitive but rigorous conclusions about the sensitivity of a chain to various types of perturbations.

  10. Asymptotic Sharpness of Bounds on Hypertrees

    Lin Yi

    2017-08-01

    Full Text Available The hypertree can be defined in many different ways. Katona and Szabó introduced a new, natural definition of hypertrees in uniform hypergraphs and investigated bounds on the number of edges of the hypertrees. They showed that a k-uniform hypertree on n vertices has at most (nk−1$\\left( {\\matrix{n \\cr {k - 1} } } \\right$ edges and they conjectured that the upper bound is asymptotically sharp. Recently, Szabó verified that the conjecture holds by recursively constructing an infinite sequence of k-uniform hypertrees and making complicated analyses for it. In this note we give a short proof of the conjecture by directly constructing a sequence of k-uniform k-hypertrees.

  11. Caffeine Increases Hippocampal Sharp Waves in Vitro.

    Watanabe, Yusuke; Ikegaya, Yuji

    2017-01-01

    Caffeine promotes memory consolidation. Memory consolidation is thought to depend at least in part on hippocampal sharp waves (SWs). In the present study, we investigated the effect of bath-application of caffeine in spontaneously occurring SWs in mouse acute hippocampal slices. Caffeine induced an about 100% increase in the event frequency of SWs at concentrations of 60 and 200 µM. The effect of caffeine was reversible after washout of caffeine and was mimicked by an adenosine A 1 receptor antagonist, but not by an A 2A receptor antagonist. Caffeine increased SWs even in dentate-CA3 mini-slices without the CA2 regions, in which adenosine A 1 receptors are abundantly expressed in the hippocampus. Thus, caffeine facilitates SWs by inhibiting adenosine A 1 receptors in the hippocampal CA3 region or the dentate gyrus.

  12. Myocardial imaging. Coxsackie myocarditis

    Wells, R.G.; Ruskin, J.A.; Sty, J.R.

    1986-09-01

    A 3-week-old male neonate with heart failure associated with Coxsackie virus infection was imaged with Tc-99m PYP and TI-201. The abnormal imaging pattern suggested myocardial infarction. Autopsy findings indicated that the cause was myocardial necrosis secondary to an acute inflammatory process. Causes of abnormal myocardial uptake of Tc-99m PYP in pediatrics include infarction, myocarditis, cardiomyopathy, bacterial endocarditis, and trauma. Myocardial imaging cannot provide a specific cause diagnosis. Causes of myocardial infarction in pediatrics are listed in Table 1.

  13. Myocardial imaging. Coxsackie myocarditis

    Wells, R.G.; Ruskin, J.A.; Sty, J.R.

    1986-01-01

    A 3-week-old male neonate with heart failure associated with Coxsackie virus infection was imaged with Tc-99m PYP and TI-201. The abnormal imaging pattern suggested myocardial infarction. Autopsy findings indicated that the cause was myocardial necrosis secondary to an acute inflammatory process. Causes of abnormal myocardial uptake of Tc-99m PYP in pediatrics include infarction, myocarditis, cardiomyopathy, bacterial endocarditis, and trauma. Myocardial imaging cannot provide a specific cause diagnosis. Causes of myocardial infarction in pediatrics are listed in Table 1

  14. Dose-dependent effects of atorvastatin on myocardial infarction

    Barbarash O

    2015-06-01

    Full Text Available Olga Barbarash, Olga Gruzdeva, Evgenya Uchasova, Ekaterina Belik, Yulia Dyleva, Victoria KaretnikovaFederal State Budgetary Institution, Research Institute for Complex Issues of Cardiovascular Diseases, Kemerovo, the Russian Federation Background: Dyslipidemia is a key factor determining the development of both myocardial infarction (MI and its subsequent complications. Dyslipidemia is associated with endothelial dysfunction, activation of inflammation, thrombogenesis, and formation of insulin resistance. Statin therapy is thought to be effective for primary and secondary prevention of complications associated with atherosclerosis.Methods: This study examined 210 patients with Segment elevated MI (ST elevated MI who were treated with atorvastatin from the first 24 hours after MI. Group 1 (n=110 were given atorvastatin 20 mg/day. Group 2 (n=100 were given atorvastatin 40 mg/day. At days 1 and 12 after MI onset, insulin resistance levels determined by the homeostasis model assessment of insulin resistance index, lipid profiles, and serum glucose, insulin, adipokine, and ghrelin levels were measured.Results: Free fatty acid levels showed a sharp increase during the acute phase of MI. Treatment with atorvastatin 20 mg/day, and especially with 40 mg/day, resulted in a decrease in free fatty acid levels. The positive effect of low-dose atorvastatin (20 mg/day is normalization of the adipokine status. Administration of atorvastatin 20 mg/day was accompanied with a statistically significant reduction in glucose levels (by 14% and C-peptide levels (by 38%, and a decrease in the homeostasis model assessment of insulin resistance index on day 12.Conclusion: Determination of atorvastatin dose and its use during the in-hospital period and subsequent periods should take into account changes in biochemical markers of insulin resistance and adipokine status in patients with MI.Keywords: myocardial infarction, statin, insulin resistance, adipokines

  15. PEROLD-SHARPE REBALANCING STRATEGIES IN PRACTICE

    Valentyn Khokhlov

    2016-11-01

    Full Text Available The purpose of this paper is to investigate the different strategies for portfolio rebalanc-ing (buy-and-hold, constant weights, and constant-proportion portfolio insurance (CPPI suggested by Perold and Sharpe in a reallife environment using the actual market data and considering trans-action costs. Methodology. Exchange-traded funds were used to represent asset classes, and actual market prices in 2007-2015 for the ETFs used to conduct the research. The Monte-Carlo simulations were used to generate 400 portfolios over 3 different time horizons in order to get a representative sample. Two actual fee structures were used from the leading U.S. brokerage firms. Results of the portfolio dynamics research show outperformance of CPPI over other strategies on holding periods over 36 months, and on shorter time horizons CPPI and constant weights strategies clearly dominate over buyand- hold strategy. Contrary to the previous conclusions by Perold and Sharpe, there was no definite link between the stock market dynamics or volatility and the preferred strategy. We also see that after a bull market period the CPPI portfolio allocation shifts to 100% equity. The portfolio turnover is typically higher and much more dispersed for CPPI strategy than for constant weights strategy. We also found a strong negative correlation between the CPPI portfolio turnover and the initial equity allocation, whereas for constant weights strategy the turnover is higher at 50% allocation to both stocks and bonds. Practical implications. The strategy choice is shown to be more a matter of the holding period; CPPI seems the best choice over longer periods. Contrary to the widespread perception, our research shows that brokerage fees has not had a material influence on the simulated portfolio performance and, thus, should not be a factor for choosing a strategy. Originality/value. Unlike previous studies in this area that focused on analytical derivation based on sample statistics

  16. A computational method for sharp interface advection

    Bredmose, Henrik; Jasak, Hrvoje

    2016-01-01

    We devise a numerical method for passive advection of a surface, such as the interface between two incompressible fluids, across a computational mesh. The method is called isoAdvector, and is developed for general meshes consisting of arbitrary polyhedral cells. The algorithm is based on the volume of fluid (VOF) idea of calculating the volume of one of the fluids transported across the mesh faces during a time step. The novelty of the isoAdvector concept consists of two parts. First, we exploit an isosurface concept for modelling the interface inside cells in a geometric surface reconstruction step. Second, from the reconstructed surface, we model the motion of the face–interface intersection line for a general polygonal face to obtain the time evolution within a time step of the submerged face area. Integrating this submerged area over the time step leads to an accurate estimate for the total volume of fluid transported across the face. The method was tested on simple two-dimensional and three-dimensional interface advection problems on both structured and unstructured meshes. The results are very satisfactory in terms of volume conservation, boundedness, surface sharpness and efficiency. The isoAdvector method was implemented as an OpenFOAM® extension and is published as open source. PMID:28018619

  17. Functional imaging of sleep vertex sharp transients.

    Stern, John M; Caporro, Matteo; Haneef, Zulfi; Yeh, Hsiang J; Buttinelli, Carla; Lenartowicz, Agatha; Mumford, Jeanette A; Parvizi, Josef; Poldrack, Russell A

    2011-07-01

    The vertex sharp transient (VST) is an electroencephalographic (EEG) discharge that is an early marker of non-REM sleep. It has been recognized since the beginning of sleep physiology research, but its source and function remain mostly unexplained. We investigated VST generation using functional MRI (fMRI). Simultaneous EEG and fMRI were recorded from seven individuals in drowsiness and light sleep. VST occurrences on EEG were modeled with fMRI using an impulse function convolved with a hemodynamic response function to identify cerebral regions correlating to the VSTs. A resulting statistical image was thresholded at Z>2.3. Two hundred VSTs were identified. Significantly increased signal was present bilaterally in medial central, lateral precentral, posterior superior temporal, and medial occipital cortex. No regions of decreased signal were present. The regions are consistent with electrophysiologic evidence from animal models and functional imaging of human sleep, but the results are specific to VSTs. The regions principally encompass the primary sensorimotor cortical regions for vision, hearing, and touch. The results depict a network comprising the presumed VST generator and its associated regions. The associated regions functional similarity for primary sensation suggests a role for VSTs in sensory experience during sleep. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  18. A computational method for sharp interface advection.

    Roenby, Johan; Bredmose, Henrik; Jasak, Hrvoje

    2016-11-01

    We devise a numerical method for passive advection of a surface, such as the interface between two incompressible fluids, across a computational mesh. The method is called isoAdvector, and is developed for general meshes consisting of arbitrary polyhedral cells. The algorithm is based on the volume of fluid (VOF) idea of calculating the volume of one of the fluids transported across the mesh faces during a time step. The novelty of the isoAdvector concept consists of two parts. First, we exploit an isosurface concept for modelling the interface inside cells in a geometric surface reconstruction step. Second, from the reconstructed surface, we model the motion of the face-interface intersection line for a general polygonal face to obtain the time evolution within a time step of the submerged face area. Integrating this submerged area over the time step leads to an accurate estimate for the total volume of fluid transported across the face. The method was tested on simple two-dimensional and three-dimensional interface advection problems on both structured and unstructured meshes. The results are very satisfactory in terms of volume conservation, boundedness, surface sharpness and efficiency. The isoAdvector method was implemented as an OpenFOAM ® extension and is published as open source.

  19. Formation of binucleated myocardial cells in the neonatal rat. An index for growth hypertrophy

    Clubb, F.J. Jr.; Bishop, S.P.

    1984-01-01

    The purposes of this study were to characterize myocardial cell growth in neonatal rats and investigate the mechanism of binucleation in myocardial cells. To test the hypothesis that binucleated myocardial cells result from karyokinesis without cytokinesis, experiments were designed to measure the rate of DNA synthesis and the percentage of binucleated myocardial cells in neonatal rats during growth. Estimates of myocardial cell nuclear divisions were obtained from rats pulsed with tritiated thymidine at 17 days of gestation. Autoradiograms were prepared from isolated myocardial cells of rats killed at various ages postpartum, and the number of developed silver halide grains over myocardial cell nuclei was calculated. This estimated the mitotic activity of nuclei. To determine myocardial cell DNA synthesis postpartum, another set of rats were injected at various time periods with 4 hourly doses of tritiated thymidine, and hearts were fixed by perfusion 1 hour later. Labeling index of myocardial cells was calculated (labeled/total myocardial cells) from autoradiograms. Results indicated that the growth of myocardial cells in period can be divided into three phases: (a) a hyperplastic phase, (b) a transitional phase, and (c) a hypertrophic phase. Binucleation of myocardial cells was not due to fusion of mononucleated cells

  20. Variational reconstruction using subdivision surfaces with continuous sharpness control

    Xiaoqun Wu; Jianmin Zheng; Yiyu Cai; Haisheng Li

    2017-01-01

    We present a variational method for subdivision surface reconstruction from a noisy dense mesh.A new set of subdivision rules with continuous sharpness control is introduced into Loop subdivision for better modeling subdivision surface features such as semi-sharp creases,creases,and corners.The key idea is to assign a sharpness value to each edge of the control mesh to continuously control the surface features.Based on the new subdivision rules,a variational model with L1 norm is formulated to find the control mesh and the corresponding sharpness values of the subdivision surface that best fits the input mesh.An iterative solver based on the augmented Lagrangian method and particle swarm optimization is used to solve the resulting non-linear,non-differentiable optimization problem.Our experimental results show that our method can handle meshes well with sharp/semi-sharp features and noise.

  1. Assessment of myocardial viability using multidetector computed tomography in patients with reperfused acute myocardial infarction

    Kim, T.; Choi, B.J.; Kang, D.K.; Sun, J.S.

    2012-01-01

    Aim: To assess the prognostic value of 64-section multidetector computed tomography (MDCT) to predict follow-up myocardial dysfunction and functional recovery after reperfusion therapy in patients with acute myocardial infarction (MI) as defined by echocardiography. Materials and methods: After reperfusion therapy for acute MI, 71 patients underwent two-phase contrast-enhanced MDCT and follow-up echocardiography. MDCT findings were compared with echocardiographic findings using kappa statistics. The areas under the receiver operating characteristic curves (AUCs) and the odds ratios (ORs) of early perfusion defects (EPD), delayed enhancement (DE), and residual perfusion defects (RPD) for predicting follow-up myocardial dysfunction and functional recovery were calculated on a segmental basis. Results: The presence of transmural EPD (EPD TM ) or RPD showed good agreement (k = 0.611 and 0.658, respectively) with follow-up myocardial dysfunction, while subendocardial EPD (EPD sub ) or subendocardial DE (DE sub ) showed fair agreement with follow-up myocardial dysfunction (k = 0.235 and 0.234, respectively). The AUC of RPD (0.796) was superior (p TM (0.761) and DE TM (0.771). The presence of EPD TM , DE TM , and RPD were significant, independent positive predictors of follow-up myocardial dysfunction (OR = 6.4, 1.9, and 9.8, respectively). EPD TM was a significant, independent negative predictor of myocardial functional recovery (OR = 0.13). Conclusion: Abnormal myocardial attenuation on two-phase MDCT after reperfusion therapy may provide promising information regarding myocardial viability in patients with acute MI.

  2. Sharp Gronwall-Bellman type integral inequalities with delay

    István Győri

    2016-11-01

    Full Text Available Various attempts have been made to give an upper bound for the solutions of the delayed version of the Gronwall-Bellman integral inequality, but the obtained estimations are not sharp. In this paper a new approach is presented to get sharp estimations for the nonnegative solutions of the considered delayed inequalities. The results are based on the idea of the generalized characteristic inequality. Our method gives sharp estimation, and therefore the results are more exact than the earlier ones.

  3. Sharp Efficiency for Vector Equilibrium Problems on Banach Spaces

    Si-Huan Li

    2013-01-01

    Full Text Available The concept of sharp efficient solution for vector equilibrium problems on Banach spaces is proposed. Moreover, the Fermat rules for local efficient solutions of vector equilibrium problems are extended to the sharp efficient solutions by means of the Clarke generalized differentiation and the normal cone. As applications, some necessary optimality conditions and sufficient optimality conditions for local sharp efficient solutions of a vector optimization problem with an abstract constraint and a vector variational inequality are obtained, respectively.

  4. The sharp edge: a frequent radiographic sign in neonatal pneumothorax

    Oestreich, A.E.

    1987-01-01

    The sharp edge sign, an unusually sharply defined silhouette of the heart and/or hemidiaphragm on frontal radiographs of the supine neonate, has been valuable in the initial recognition of pneumothorax. In a prospective study of 50 neonatal pneumothoraces, a sharp edge sign was present on the initial pneumothorax film 49 times. In seven of these, only the hemidiaphragm showed a sharp edge, while the heart margin was superimposed on the vertebral column. Greater awareness of the sharp edge sign would promote earlier recognition of neonatal pneumothorax. 6 refs.; 3 figs

  5. Cardiovascular MR T2-STIR imaging does not discriminate between intramyocardial haemorrhage and microvascular obstruction during the subacute phase of a reperfused myocardial infarction

    Hansen, Esben Søvsø Szocska; Pedersen, Steen Fjord; Pedersen, Steen Bønløkke

    2016-01-01

    ) and T2 weighted short tau inversion recovery (T2-STIR) imaging have been used to detect IMH and to explore its clinical importance. IMH is typically identified within the area-at-risk as a hypointense signal core on T2-STIR images. Because MVO will also appear as a hypointense signal core, T2-STIR...... imaging may not be an optimal method for assessing IMH. In this study, we sought to investigate the ability of T2-STIR to discriminate between MVO with IMH in a porcine myocardial ischaemia-reperfusion model that expressed MVO with and without IMH. METHOD: MVO with and without IMH (defined from both...... MVO in all hearts. CMR and pathology showed that IMH was present in 6 of 13 (46%) infarcts. The sensitivity and specificity of T2-STIR hypointense signal core for identification of IMH was 100% and 29%, respectively. T2-values between hypointense signal core in the pigs with and without IMH were...

  6. Role of myocardial perfusion imaging in evaluating thrombolytic therapy for acute myocardial infarction

    Beller, G.A.

    1987-01-01

    Myocardial thallium-201 scintigraphy is being increasingly employed as a method for assessing the efficacy of coronary reperfusion in acute myocardial infarction. New thallium uptake after intracoronary tracer administration after successful recanalization indicates that nutrient blood flow has been successfully restored. One may also presume that some myocardial salvage occurred if thallium administered in this manner is transported intracellularly by myocytes with intact sarcolemmal membranes. However, if one injects thallium by way of the intracoronary route immediately after reperfusion, the initial uptake of thallium in reperfused myocardium may predominantly represent hyperemic flow and regional thallium counts measured may not be proportional to the mass of viable myocytes. When thallium is injected intravenously during the occlusion phase the degree of redistribution after thrombolysis is proportional to the degree of flow restoration and myocardial viability. When thallium is injected for the first time intravenously immediately after reperfusion, an overestimation of myocardial salvage may occur because of excess thallium uptake in the infarct zone consequent to significant hyperemia. Another approach to myocardial thallium scintigraphy in patients undergoing thrombolytic therapy is to administer two separate intravenous injections before and 24 hours or later after treatment. Finally, patients with acute myocardial infarction who receive intravenous thrombolytic therapy are candidates for predischarge exercise thallium-201 scintigraphy for risk stratification and detection of residual ischemia

  7. Cardiopulmonary exercise testing in the early-phase of myocardial infarction Teste de exercício cardiopulmonar na fase precoce do infarto do miocárdio

    Vandeni C. Kunz

    2012-10-01

    Full Text Available OBJECTIVE: To evaluate and to compare the cardiorespiratory and metabolic variables at the ventilatory anaerobic threshold level (AT and at submaximal cardiopulmonary exercise testing (CPET in both, healthy volunteers and in patients in the early phase after acute myocardial infarction (AMI. METHOD: Twenty-six volunteers underwent a submaximal or symptom-limited cardiopulmonary exercise testing (CPET on a cycle ergometer and were divided into AMI group (AMIG=12, 56.33±8.65 years and healthy group (CG=14, 53.33±3.28 years. The primary outcome measures were the cardiorespiratory and metabolic variables obtained at the peak workload and at the AT of the CPET. Statistical test: independent Student's t-test, α=5%. RESULTS: The AMIG presented lower values at the AT and the peak workload of the CPET compered to the CG: power in watts (91.06±30.10 and 64.88±19.92; 154.93±34.65 and 120.40±29.60; VO2 mL.kg-1.min-1 (17.26±2.71 and 12.19±2.51; 25.39±5.73 and 19.41±5.63; VCO2 L/min-1 (1.43±0.31 and 0.93±0.23; 2.07±0.43 and 1.42±0.36, VO2 L/min-1 (1.33±0.32 and 1.00±0.23; 1.97±0.39 and 1.49±0.36; VE L/min-1 (42.13±8.32 and 27.51±5.86; 63.07±20.83 and 40.82±11.96; HR (bpm (122.96±14.02 and 103.46±13.38; 149.67±13.77 and 127.60±10.04, double product (DP (bpm.mmHg.min-1 (21835.86±3245.93 and 17333.25±2716.51; 27302.33±3053.08 and 21864.00±2051.48, respectively. The variable oxygen uptake efficiency slope (OUES L/min was lower in the AMIG (1.79±0.51 than the CG (2.26±0.37. The AMIG presented neither ECG alterations nor symptoms that limited the CPET. CONCLUSION: The results suggest that patients with AMI Killip class I presented lower functional capacity and DP compared to the CG without presenting ischemic alterations. Thus, the study suggests that submaximal CPET can be applied at an early stage to evaluate cardiorespiratory status since it is both safe and highly sensitive to detect changes.OBJETIVO: Avaliar e comparar as vari

  8. Hydrodynamic processes in sharp meander bends and their morphological implications

    Blanckaert, K.

    2011-01-01

    The migration rate of sharp meander bends exhibits large variance and indicates that some sharply curved bends tend to stabilize. These observations remain unexplained. This paper examines three hydrodynamic processes in sharp bends with fixed banks and discusses their morphological implications:

  9. Sharp foreign body ingestion by a young girl

    Riyadh Mohamad Hasan

    2017-06-09

    Jun 9, 2017 ... Sharp foreign body ingestion by a young girl. Riyadh Mohamad Hasan. University of Baghdad ... ray imaging and retrieved with the aid of C-arm fluoroscope at a laparotomy. Her postoperative period ... In our patient the foreign bodies were long sharp ones (sewing needles). Foreign body ingestion can be ...

  10. Efficacy and safety of a novel pharmacological stress test agent-higenamine in radionuclide myocardial perfusion imaging: phase Ⅱ clinical trial

    Du Yanrong; Li Fang; Wang Qian; Li Dianfu; Long Mingqing; Liu Yimin; Li Bilu

    2014-01-01

    Objective: To evaluate the effectiveness and safety of higenamine (HG), a pharmaco logical stress agent, for the detection of myocardial ischemia using SPECT. Methods: This study was an open,multi-center, randomized and positively controlled trial with crossover references. It consisted of 120 patients clinically confirmed or suspected of myocardial ischemia. Each patient underwent a resting MPI and two separate stress MPI in a randomized crossover manner with intravenous administration of HG or adenosine (Ad) on different days. The severity and extent of myocardial ischemia were diagnosed on stress MPI. The degree of vascular stenosis in terms of percentage narrowing was measured by CAG (>50% was defined as coronary disease), thus defined as gold standard. The diagnostic efficacy of HG and Ad was compared. Vital signs, routine blood and urine tests,blood biochemical items and side effects were documented for evaluation of procedure safety. Two-sample t test, χ 2 or Fisher's exact test, and Kappa test were used. Results: A total of 109 patients completed the trim and CAG. The diagnostic sensitivity, specificity, accuracy, positive predictive value, negative predictive value of HG MPI were 56.1% (32/57), 78.8% (41/52), 67.0%(73/109), 74.4% (32/43) and 62.1% (41/66), respectively, which were not significantly different from those of Ad MPI (52.6% (30/57), 82.7% (43/52), 67.0% (73/109), 76.9% (30/39) and 61.4%(43/70) ; χ 2 =0-0.2476, all P>0.05). The sensitivity of HG vs Ad MPI in the diagnosis of single-, double-and triple-vessel ischemia was 29.6% (8/27) vs 22.2% (6/27), 64.7% (11/17) vs 64.7% (11/17) and 100% (13/13) vs 100% (13/13), respectively. The concordance between HG and Ad for the detection of LAD, LCX and RCA ischemia was 95.41% (104/109), 97.25% (106/109) and 97.25% (106/109) (Kappa=0.8905, 0.8420 and 0.8874). HG did not induce significant systolic blood pressure change during or after administration. Both HG and Ad could induce temporary decrease

  11. Periodontitis and myocardial hypertrophy.

    Suzuki, Jun-Ichi; Sato, Hiroki; Kaneko, Makoto; Yoshida, Asuka; Aoyama, Norio; Akimoto, Shouta; Wakayama, Kouji; Kumagai, Hidetoshi; Ikeda, Yuichi; Akazawa, Hiroshi; Izumi, Yuichi; Isobe, Mitsuaki; Komuro, Issei

    2017-04-01

    There is a deep relationship between cardiovascular disease and periodontitis. It has been reported that myocardial hypertrophy may be affected by periodontitis in clinical settings. Although these clinical observations had some study limitations, they strongly suggest a direct association between severity of periodontitis and left ventricular hypertrophy. However, the detailed mechanisms between myocardial hypertrophy and periodontitis have not yet been elucidated. Recently, we demonstrated that periodontal bacteria infection is closely related to myocardial hypertrophy. In murine transverse aortic constriction models, a periodontal pathogen, Aggregatibacter actinomycetemcomitans markedly enhanced cardiac hypertrophy with matrix metalloproteinase-2 activation, while another pathogen Porphyromonas gingivalis (P.g.) did not accelerate these pathological changes. In the isoproterenol-induced myocardial hypertrophy model, P.g. induced myocardial hypertrophy through Toll-like receptor-2 signaling. From our results and other reports, regulation of chronic inflammation induced by periodontitis may have a key role in the treatment of myocardial hypertrophy. In this article, we review the pathophysiological mechanism between myocardial hypertrophy and periodontitis.

  12. The relationship between myocardial blood flow and myocardial viability after reperfusion. Myocardial viability assessed by 15O-water-PET

    Tsukagoshi, Joichi

    1994-01-01

    The purpose of this study was to examine the relationship between myocardial blood flow and myocardial viability in the ischemic canine myocardium after reperfusion. Transient ischemia was induced by 60-, 90-, and 180-minute occlusion of the left anterior descending coronary artery. Myocardial blood flow (MBF) was measured in the areas in which regional contractility was severely impaired (ehocardiographically akinetic or dyskinetic) in the early reperfusion period by 15 O-water positron emission tomography (PET) 12 hours and 4 weeks after reperfusion. An MBF ratio of ischemic to nonischemic regions 12 hours after reperfusion was inversely correlated with the amount of histologically determined tissue necrosis (r=-0.74). The regional contractility recovered 4 weeks later in the areas where an MBF ratio was 0.48 or greater, but did not recover in the areas with a lower MBF ratio. Thus, myocardial viability can be appropriately predicted in the early phase of myocardial perfusion by PET with 15 O-water even in the absence of metabolic imaging. (author)

  13. An alternative window upon the GSI sharp lepton problem

    Griffin, J.J.

    1997-10-01

    Two major heavy ion studies of the GSI ''(e + e - )-Puzzle'' have ended in stalemate: APEX reports no evidence, but its data show a peak near 800 keV. EPOS/II cannot reproduce its own results,and leans towards random fluctuations as the explanation of sharp pair lines. (But one EPOS/II report shows evidence for a peak at an EPOS/I line energy, 610 keV, and under selection conditions the same as EPOSII's.) It is clear that these latest heavy ion studies, designed to settle once and for all the question of sharp pairs, have failed to fulfill that goal. Attention must now turn towards the sharp electron lines reported by Sakai et al. and others in collisions of few MeV beta decay positrons on U and Th atoms. In the Q 0 Scenario of the Sharp Lepton Problem these arise from the same source as the GSI pairs. Verification of Sakai's 100 mb cross section for such sharp electrons in collisions of few MeV electrons (or positrons) upon U or Th atoms would confirm this new experimental window upon the Sharp Lepton Problem. These relatively simple experiments, which are both inexpensive and reproducible (as their heavy ion counterparts are not), promise a less ponderous pace for the study of these questions. On the other hand, they require a challenging combination of proficiencies to measure a nuclear sized cross section in an atomic physics environment. The authors review briefly the diverse history (and especially the most recent developments) of the Sharp Lepton Problem, and outline how the Quadronium Scenario provides it with a unifying conceptual framework. That discussion points clearly towards the experimental study of sharp leptons and sharp pairs from few MeV (lepton+ATOM) and (photon+ATOM) processes as the appropriate next step towards either verifying the earlier results or precluding them

  14. Mechanisms of sharp wave initiation and ripple generation.

    Schlingloff, Dániel; Káli, Szabolcs; Freund, Tamás F; Hájos, Norbert; Gulyás, Attila I

    2014-08-20

    Replay of neuronal activity during hippocampal sharp wave-ripples (SWRs) is essential in memory formation. To understand the mechanisms underlying the initiation of irregularly occurring SWRs and the generation of periodic ripples, we selectively manipulated different components of the CA3 network in mouse hippocampal slices. We recorded EPSCs and IPSCs to examine the buildup of neuronal activity preceding SWRs and analyzed the distribution of time intervals between subsequent SWR events. Our results suggest that SWRs are initiated through a combined refractory and stochastic mechanism. SWRs initiate when firing in a set of spontaneously active pyramidal cells triggers a gradual, exponential buildup of activity in the recurrent CA3 network. We showed that this tonic excitatory envelope drives reciprocally connected parvalbumin-positive basket cells, which start ripple-frequency spiking that is phase-locked through reciprocal inhibition. The synchronized GABA(A) receptor-mediated currents give rise to a major component of the ripple-frequency oscillation in the local field potential and organize the phase-locked spiking of pyramidal cells. Optogenetic stimulation of parvalbumin-positive cells evoked full SWRs and EPSC sequences in pyramidal cells. Even with excitation blocked, tonic driving of parvalbumin-positive cells evoked ripple oscillations. Conversely, optogenetic silencing of parvalbumin-positive cells interrupted the SWRs or inhibited their occurrence. Local drug applications and modeling experiments confirmed that the activity of parvalbumin-positive perisomatic inhibitory neurons is both necessary and sufficient for ripple-frequency current and rhythm generation. These interneurons are thus essential in organizing pyramidal cell activity not only during gamma oscillation, but, in a different configuration, during SWRs. Copyright © 2014 the authors 0270-6474/14/3411385-14$15.00/0.

  15. Myocardial imaging in acute myocardial infarction using β-methyl-p-(123I)-iodophenylpentadecanoic acid

    Naruse, Hitoshi; Itano, Midoriko; Kondo, Tomohiro

    1992-01-01

    Myocardial imaging using β-methyl-p-( 123 I)-iodophenylpentadecanoic acid (BMIPP) was performed in 11 patients with acute myocardial infarction. The left ventricular images were divided into 12 segments, and myocardial images with BMIPP were compared with coronary angiography (CAG), thallium-201 myocardial scintigraphy (Tl) and wall motion obtained by two-dimensional echocardiography (WM). When the culprit lesion was at the proximal point of the left anterior descending artery (LAD), all segments showed depressed uptake. In 3 cases with single vessel disease of the LAD, inferior wall of the basis showed reduced uptake of BMIPP despite the location of the culprit lesion. In cases with discordant uptake between the two tracers, BMIPP frequently showed more severely depressed uptake than Tl in the subacute phase, although the uptake of BMIPP correlated with that of Tl (τ=0.82, p<0.001). In such cases, the discordance was related to the improvement in WM from the acute phase to the convalescent phase. BMIPP uptake correlated with WM in the subacute phase (τ=0.50, p<0.001). BMIPP showed more severely depressed uptake while WM showed mild asynergy in most cases in which discordance was found between the BMIPP and WM findings. However, there was no correlation between the change in WM from the acute to subacute phases, or the uptakes of BMIPP and Tl alone. We concluded that the myocardial condition can be evaluated in detail in acute myocardial infarction by comparing the findings of BMIPP with those of Tl and WM. (author)

  16. Lack of benefit from percutaneous intervention of persistently occluded infarct arteries after the acute phase of myocardial infarction is time independent: insights from Occluded Artery Trial

    Menon, Venu; Pearte, Camille A.; Buller, Christopher E.; Steg, Ph.Gabriel; Forman, Sandra A.; White, Harvey D.; Marino, Paolo N.; Katritsis, Demosthenes G.; Caramori, Paulo; Lasevitch, Ricardo; Loboz-Grudzien, Krystyna; Zurakowski, Aleksander; Lamas, Gervasio A.; Hochman, Judith S.

    2009-01-01

    Aims The Occluded Artery Trial (OAT) (n = 2201) showed no benefit for routine percutaneous intervention (PCI) (n = 1101) over medical therapy (MED) (n = 1100) on the combined endpoint of death, myocardial infarction (MI), and class IV heart failure (congestive heart failure) in stable post-MI patients with late occluded infarct-related arteries (IRAs). We evaluated the potential for selective benefit with PCI over MED for patients enrolled early in OAT. Methods and results We explored outcomes with PCI over MED in patients randomized to the ≤3 calendar days and ≤7 calendar days post-MI time windows. Earlier, times to randomization in OAT were associated with higher rates of the combined endpoint (adjusted HR 1.04/day: 99% CI 1.01–1.06; P < 0.001). The 48-month event rates for ≤3 days, ≤7 days post-MI enrolled patients were similar for PCI vs. MED for the combined and individual endpoints. There was no interaction between time to randomization defined as a continuous (P = 0.55) or categorical variable with a cut-point of 3 days (P = 0.98) or 7 days (P = 0.64) post-MI and treatment effect. Conclusion Consistent with overall OAT findings, patients enrolled in the ≤3 day and ≤7 day post-MI time windows derived no benefit with PCI over MED with no interaction between time to randomization and treatment effect. Our findings do not support routine PCI of the occluded IRA in trial-eligible patients even in the earliest 24–72 h time window. PMID:19028780

  17. Sharp tipped plastic hollow microneedle array by microinjection moulding

    Yung, K. L.; Xu, Yan; Kang, Chunlei; Liu, H.; Tam, K. F.; Ko, S. M.; Kwan, F. Y.; Lee, Thomas M. H.

    2012-01-01

    A method of producing sharp tipped plastic hollow microneedle arrays using microinjection moulding is presented in this paper. Unlike traditional approaches, three mould inserts were used to create the sharp tips of the microneedles. Mould inserts with low surface roughness were fabricated using a picosecond laser machine. Sharp tipped plastic hollow microneedles 500 µm in height were fabricated using a microinjection moulding machine developed by the authors’ group. In addition, the strength of the microneedle was studied by simulation and penetration experiments. Results show that the microneedles can penetrate into skin, delivering liquid successfully without any breakage or severe deformation. Techniques presented in this paper can be used to fabricate sharp tipped plastic hollow microneedle arrays massively with low cost.

  18. Sharp tipped plastic hollow microneedle array by microinjection moulding

    Yung, K L; Xu, Yan; Kang, Chunlei; Liu, H; Tam, K F; Ko, S M; Kwan, F Y; Lee, Thomas M H

    2012-01-01

    A method of producing sharp tipped plastic hollow microneedle arrays using microinjection moulding is presented in this paper. Unlike traditional approaches, three mould inserts were used to create the sharp tips of the microneedles. Mould inserts with low surface roughness were fabricated using a picosecond laser machine. Sharp tipped plastic hollow microneedles 500 µm in height were fabricated using a microinjection moulding machine developed by the authors’ group. In addition, the strength of the microneedle was studied by simulation and penetration experiments. Results show that the microneedles can penetrate into skin, delivering liquid successfully without any breakage or severe deformation. Techniques presented in this paper can be used to fabricate sharp tipped plastic hollow microneedle arrays massively with low cost. (paper)

  19. The effectiveness of sharp end and rounded end bristle toothbrush

    Paulus Januar; Anastasia Susetyo; Ratih Widyastuti

    2010-01-01

    Background: Numerous designs of manual toothbrush are available in the market with the claims of superiority in plaque removal. It often makes the public confuse which is the best design. The sharp end bristle toothbrush is a modification that commercially available in the market. Purpose: The objective of the study was to compare the effectiveness in plaque removal of the sharp end bristle toothbrush and the rounded end bristle toothbrush. Methods: This clinical trial was a double blind cros...

  20. The sharp peak-flat trough pattern and critical speculation

    Roehner, B. M.; Sornette, D.

    1998-01-01

    We find empirically a characteristic sharp peak-flat trough pattern in a large set of commodity prices. We argue that the sharp peak structure reflects an endogenous inter-market organization, and that peaks may be seen as local ``singularities'' resulting from imitation and herding. These findings impose a novel stringent constraint on the construction of models. Intermittent amplification is not sufficient and nonlinear effects seem necessary to account for the observations.

  1. Clinical usefulness of technetium-99m pyrophosphate and Tl-201 myocardial imaging for the estimation of myocardial infarction

    Suzuki, Akio; Sato, Akihiko; Miyakoda, Hiroyuki; Watanabe, Toshiya; Itatsu, Hidetaka; Ueda, Osamu; Sakurai, Kuniteru; Kawai, Naoki; Sotobata, Iwao

    1985-04-01

    A correlative study was performed between the infarct size estimated by either technetium-99 pyrophosphate (Tc-PYP) or Tl-201 myocardial imaging, and the cumulative total creatinine phosphokinase activity (..sigma..CPK) or left ventricular ejection fraction (LVEF) in 40 patients with acute myocardial infarction. Tc-PYP infarct area (TcIA) and mean Tl-201 uptake ratio (MUR) were calculated as indices of myocardial infarct size. LVEF was evaluated by first pass method using Tc-PYP in the acute phase of myocardial infraction. In 23 patients with anterior myocardial infarction, a significant correlation was shown between either TcIA or anterior-wall MUR and ..sigma..CPK (r=0.81 and r=-0.69, respectively) and also between either TcIA or anterior-wall MUR and LVEF (r=-0.84 and r=0.80, respectively). In 17 patients with inferior myocardial infarction without additional involvement of right ventricular wall, inferior-wall MUR correlated with ..sigma..CPK (r=-0.74). No statically significant correlation was shown between TcIA and ..sigma..CPK, and also between either TcIA or inferior-wall MUR and LVEF. In conclusion, the infarct size estimated with Tc-PYP or Tl-201 myocardial imaging could be a useful clinical indicator of the severity of acute myocardial infarction especially in anterior wall. (author).

  2. Sharps injury reduction using a sharps container with enhanced engineering: a 28 hospital nonrandomized intervention and cohort study.

    Grimmond, Terry; Bylund, Suzann; Anglea, Candace; Beeke, Lou; Callahan, Angela; Christiansen, Erik; Flewelling, Kelly; McIntosh, Kathleen; Richter, Kay; Vitale, Monica

    2010-12-01

    The decrease in reported sharps injuries (SI) in the United States has markedly slowed. Additional devices and strategies need investigation. Sharps containers are associated with SI, and more than 90% of these injuries are related to container design. This study addresses the hypothesis that containers with enhanced engineering can reduce SI. In a before/after intervention study from 2006 to 2008, we examined the impact of conversion to a sharps container with enhanced engineering (the Device) on SI categories in 14 Ascension Health hospitals (study group). The Device's safety features included large horizontal aperture, sensitive counterbalanced door, large atrium, and passive overfill prevention. Study group results were also compared with a control cohort of 14 contemporaneous size-matched, Ascension Health hospitals (control group). The Device was associated with significant reductions in after-procedure (-30%), disposal-related (-57%), and container-associated (-81%) SI in the study group. No significant reductions occurred in container-associated sharps injuries in the control group. Hospitals using the Device had significantly fewer total SI than control hospitals. Enhanced aperture design can significantly reduce container-associated sharps injuries. Other factors contributing to reduced injuries may include 1-hand deposit, safe closure, hand restriction, and preassembly. These results, from a country where sharps safety devices are widespread, are particularly applicable to countries where safety devices are not extensively used. Copyright © 2010 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  3. Acceleration of tissue phase mapping by k-t BLAST: a detailed analysis of the influence of k-t-BLAST for the quantification of myocardial motion at 3T

    Nienhaus G Ulrich

    2011-01-01

    Full Text Available Abstract Background The assessment of myocardial motion with tissue phase mapping (TPM provides high spatiotemporal resolution and quantitative motion information in three directions. Today, whole volume coverage of the heart by TPM encoding at high spatial and temporal resolution is limited by long data acquisition times. Therefore, a significant increase in imaging speed without deterioration of the quantitative motion information is required. For this purpose, the k-t BLAST acceleration technique was combined with TPM black-blood functional imaging of the heart. Different k-t factors were evaluated with respect to their impact on the quantitative assessment of cardiac motion. Results It is demonstrated that a k-t BLAST factor of two can be used with a marginal, but statistically significant deterioration of the quantitative motion data. Further increasing the k-t acceleration causes substantial alteration of the peak velocities and the motion pattern, but the temporal behavior of the contraction is well maintained up to an acceleration factor of six. Conclusions The application of k-t BLAST for the acceleration of TPM appears feasible. A reduction of the acquisition time of almost 45% could be achieved without substantial loss of quantitative motion information.

  4. The Influence of findings of coronary artery on myocardial salvage in acute myocardial infarction

    Itano, Midoriko; Naruse, Hitoshi; Morita, Masato; Kawamoto, Hideo; Yamamoto, Juro; Fukutake, Naoshige; Ohyanagi, Mitsumasa; Iwasaki, Tadaaki; Fukuchi, Minoru

    1992-01-01

    201 Tl stress myocardial scintigraphy was performed in convalescent patients with acute myocardial infarction, to evaluate the influence of stenosis and collateral circulation of coronary artery in acute phase, on myocardial salvage in chronic phase. In 14 cases of unsuccessful coronary revascularization (complete occlusion), a complete defect of thallium imaging in chronic phase was seen in only one case of four cases with good collateral circulation, while eight of 10 cases with poor collateral circulation. In 16 cases with collateral circulation, six cases showed a complete defect, although the target vessel had improved to less than 75% of stenosis. However, in cases of good collateral circulation, no case showed a complete defect when the target vessel had improved to less than 75% of stenosis. The myocardial salvage is quite possible (p<0.05), when the coronary angiography in acute phase showed the forward flow (99% or 90% of stenosis) before coronary revascularization and/or good collateral circulation (Rentrop 2deg or 3deg). (author)

  5. The values of myocardial tomography imaging and gated cardiac blood pool imaging in detecting left ventricular aneurysm

    Zhu Mei; Pan Zhongyun; Li Jinhui

    1992-01-01

    The sensitivity and specificity of myocardial tomography imaging and gated cardiac blood-pool imaging in detecting LVA were studied in 36 normal subjects and 68 patients with myocardial infarction. The sensitivities of exercise and rest myocardial imaging in detecting LVA were 85% and 77.3% respectively. The specificity of both is 95.5%. The sensitivity of cinema display, phase analysis and left ventricular phase shift in evaluating LVA were 86.7%, 86.7%, 100% respectively. Their specificity were all 100%. It is concluded that blood pool imaging is of choice for the diagnosis of LVA, and that myocardial imaging could also demonstrate LVA during diagnosing myocardial infarction

  6. Myocardial scintigraphy with thallium-201

    Lichte, H [Zentralkrankenhaus Gauting (Germany, F.R.). Nuklearmedizinische Abt.

    1977-04-01

    Myocardial scintigraphy with /sup 201/thallium is a non-invasive method for detection of myocardial infarction and coronary heart disease. Redistribution-analysis as a sequential-scintigraphy of an exercise-scan permits to distinguish between myocardial scars and coronary vessel disease.

  7. Heterogeneous sharpness for cross-spectral face recognition

    Cao, Zhicheng; Schmid, Natalia A.

    2017-05-01

    Matching images acquired in different electromagnetic bands remains a challenging problem. An example of this type of comparison is matching active or passive infrared (IR) against a gallery of visible face images, known as cross-spectral face recognition. Among many unsolved issues is the one of quality disparity of the heterogeneous images. Images acquired in different spectral bands are of unequal image quality due to distinct imaging mechanism, standoff distances, or imaging environment, etc. To reduce the effect of quality disparity on the recognition performance, one can manipulate images to either improve the quality of poor-quality images or to degrade the high-quality images to the level of the quality of their heterogeneous counterparts. To estimate the level of discrepancy in quality of two heterogeneous images a quality metric such as image sharpness is needed. It provides a guidance in how much quality improvement or degradation is appropriate. In this work we consider sharpness as a relative measure of heterogeneous image quality. We propose a generalized definition of sharpness by first achieving image quality parity and then finding and building a relationship between the image quality of two heterogeneous images. Therefore, the new sharpness metric is named heterogeneous sharpness. Image quality parity is achieved by experimentally finding the optimal cross-spectral face recognition performance where quality of the heterogeneous images is varied using a Gaussian smoothing function with different standard deviation. This relationship is established using two models; one of them involves a regression model and the other involves a neural network. To train, test and validate the model, we use composite operators developed in our lab to extract features from heterogeneous face images and use the sharpness metric to evaluate the face image quality within each band. Images from three different spectral bands visible light, near infrared, and short

  8. Four year-old girl with having bled intestinal sharp

    Rodriguez Toro, Gerzain

    2001-01-01

    Indigenous girl, natural of Vaupes, Colombia conduction to the Mitu Hospital to present depositions with bleed. Their father says that the girl is sick for two days; she presents anorexia, moderate abdominal pain and vomit scarce postprandial, followed by discreet diarrhea and of two depositions with blood and abundant clots, with posterior syncope. It confirms a bled digestive with sharp anemic syndrome. The possibilities of gastritis sharp erosive, gastric ulcer or duodenal and intestinal poliparasitism are suggested. It is diagnosed abdominal angioestrongilosis, illness produce by helminths that lives inside the blind and the distal ileum

  9. SHARP's systems engineering challenge: rectifying integrated product team requirements with performance issues in an evolutionary spiral development acquisition

    Kuehl, C. Stephen

    2003-08-01

    Completing its final development and early deployment on the Navy's multi-role aircraft, the F/A-18 E/F Super Hornet, the SHAred Reconnaissance Pod (SHARP) provides the war fighter with the latest digital tactical reconnaissance (TAC Recce) Electro-Optical/Infrared (EO/IR) sensor system. The SHARP program is an evolutionary acquisition that used a spiral development process across a prototype development phase tightly coupled into overlapping Engineering and Manufacturing Development (EMD) and Low Rate Initial Production (LRIP) phases. Under a tight budget environment with a highly compressed schedule, SHARP challenged traditional acquisition strategies and systems engineering (SE) processes. Adopting tailored state-of-the-art systems engineering process models allowd the SHARP program to overcome the technical knowledge transition challenges imposed by a compressed program schedule. The program's original goal was the deployment of digital TAC Recce mission capabilities to the fleet customer by summer of 2003. Hardware and software integration technical challenges resulted from requirements definition and analysis activities performed across a government-industry led Integrated Product Team (IPT) involving Navy engineering and test sites, Boeing, and RTSC-EPS (with its subcontracted hardware and government furnished equipment vendors). Requirements development from a bottoms-up approach was adopted using an electronic requirements capture environment to clarify and establish the SHARP EMD product baseline specifications as relevant technical data became available. Applying Earned-Value Management (EVM) against an Integrated Master Schedule (IMS) resulted in efficiently managing SE task assignments and product deliveries in a dynamically evolving customer requirements environment. Application of Six Sigma improvement methodologies resulted in the uncovering of root causes of errors in wiring interconnectivity drawings, pod manufacturing processes, and avionics

  10. Characteristics of 201Tl myocardial SPECT and left ventriculography in patients with acute diagonal branch myocardial infarction

    Tanaka, Takeshi; Aizawa, Tadanori; Katou, Kazuzo; Ogasawara, Ken; Kirigaya, Hajime

    1993-01-01

    Characteristics of 201 Tl myocardial SPECT and ventriculography were studied in 13 patients with acute diagonal branch myocardial infarction. Rest 201 Tl myocardial SPECT and left ventriculography were underwent in chronic phase. In 5 patients electrocardiogram (ECG) changes in acute phase were not definite. In 6 patients it was difficult to identify the obstructed coronary artery with coronary angiography in acute phase. Mean value of maximum creatine phosphokinese (CPK) was 854 (458-1,774) U/l. It seemed to be difficult to diagnose acute diagonal branch myocardial infarction with ECG and/or coronary angiography. In all patients defects were noted on 201 Tl SPECT. Defects were small and noted in the central anterior wall and not in the septum. In 2 patients defects were noted at apex. In left ventriculography dyskinetic motion was noted in 10 patients; one patient showed apical aneurysm and 3 patients showed anterior wall aneurysm. In 3 patients anterior wall showed akinesis. It was concluded that 201 Tl myocardial SPECT were useful for detecting diagonal branch lesion. In case of diagonal branch myocardial infarction size of defects were small and defects were not noted in the septum, however aneurysmal motion was frequently noted. (author)

  11. Myocardial myoglobin release after acute myocardial infarction

    Robinson, P S; Saltissi, S; Coltart, D J; Croft, D N [Saint Thomas' Hospital, London (UK)

    1980-03-01

    The magnitude and time course of myoglobin release from the myocardium following infarction was assessed by radioimmunoassay. The assay showed acceptable precision over a working range from 50 to 750 ng cm/sup -3/, provided careful control of the assay temperature was maintained. The use of this radioimmunoassay as an early diagnostic test for infarction and as a potential measure of the extent of necrosis is considered and comparison made with the release of CK-MB, the myocardial specific isoenzyme of creatine kinase. Of the twenty patients studied with myocardial infarction, all had elevated levels of serum myoglobin including those admitted within 3 hours of the onset of pain. In contrast, CK-MB was not detected in the serum within 5 hours of the onset of pain. Peak serum levels of myoglobin (mean 852 +- 365 ng cm/sup -3/) and CK-MB (mean 71 +- 25 mIU cm/sup -3/) were detected at 8-16 hours and 20-24 hours respectively after the onset of pain. A comparison of peak serum levels of myoglobin and CK-MB showed a good correlation (r = 0.84).

  12. Reversible myocardial ischaemia or irreversible myocardial fibrosis

    Mathey, D.; Hanrath, P.; Kupper, W.; Bleifeld, W.; Montz, R.; Knop, J.; Stritzke, P.; Kroeger, E.; Bleese, N.

    1978-01-01

    The results of biphasis 201 thallium ( 201 Tl) scanning were compared with those of coronary arteriography, left ventricular angiography and stress ECG in 56 patients with coronary artery disease and six with no evidence of heart disease. There were 104 201 Tl defects, 50 of them reversible. The defects were always located in the area supplied by a critically stenotic coronary artery. Correlation of regional wall motion with 201 Tl activity demonstrated that in all forms of abnormal wall motion there was either ischaemia or fibrosis. The resting LV angiogram thus does not make it possible to distinguish between myocardial ischaemia and fibrosis. Taking the LV angiogram as a standard, the rate of false-positive 201 Tl scintigrams was 5%, that of false-negative ones 23%. The biphasic 201 Tl scintigram was more sensitive than the stress ECG in detecting myocardial ischaemia. It furthermore made it possible to localize the ischaemic (or fibrotic) region within the LV and to estimate its size. (orig.) [de

  13. Focusing optical waves with a rotationally symmetric sharp-edge aperture

    Hu, Yanwen; Fu, Shenhe; Li, Zhen; Yin, Hao; Zhou, Jianying; Chen, Zhenqiang

    2018-04-01

    While there has been various kinds of patterned structures proposed for wave focusing, these patterned structures usually involve complicated lithographic techniques since the element size of the patterned structures should be precisely controlled in microscale or even nanoscale. Here we propose a new and straightforward method for focusing an optical plane wave in free space with a rotationally symmetric sharp-edge aperture. The focusing phenomenon of wave is realized by superposition of a portion of the higher-order symmetric plane waves generated from the sharp edges of the apertures, in contrast to previously focusing techniques which usually depend on a curved phase. We demonstrate both experimentally and theoretically the focusing effect with a series of apertures having different rotational symmetry, and find that the intensity of the hotspots could be controlled by the symmetric strength of the sharp-edge apertures. The presented results would advance the conventional wisdom that light would diffract in all directions and become expanding when it propagates through an aperture. The proposed method is easy to be processed, and might open potential applications in interferometry, image, and superresolution.

  14. Two New Sharp Ostrowski-Grüss Type Inequalities

    Zheng Liu

    2013-11-01

    Full Text Available The purpose of this paper is to use a variant of the Grüss inequality to derive two new sharp Ostrowski-Grüss type inequalities related to a perturbed trapezoidal type rule and a perturbed generalized interior point rule, respectively, which provide improvements of some previous results in the literatures.

  15. Conservative sharp debridement: the professional and legal issues.

    Ashworth, Jenny; Chivers, Marc

    2002-06-01

    In recent years there has been much debate over the use of conservative sharp debridement in the treatment of certain wound types. Here it is discussed in relation to increasing the speed of wound healing in slow-to-heal wounds. The authors examine education and skill competence in relation to the professional's duty of care to patients with wounds.

  16. Sharp Injuries Among Hospital Waste Handlers | Olaitan | Nigerian ...

    , C as well as other before commencing on their jobs. Workers should be screened for infective diseases that can be of legal problem while at the job and the workers should be effectively immunized. Key words: sharp injuries, waste, handlers, ...

  17. Herbivores Enforce Sharp Boundaries Between Terrestrial and Aquatic Ecosystems

    Sarneel, Judith M.; Huig, N.; Veen, G. F.; Rip, W.; Bakker, E. S.

    2014-01-01

    The transitions between ecosystems (ecotones) are often biodiversity hotspots, but we know little about the forces that shape them. Today, often sharp boundaries with low diversity are found between terrestrial and aquatic ecosystems. This has been attributed to environmental factors that hamper

  18. Sharp Bounds for Symmetric and Asymmetric Diophantine Approximation

    Cornelis KRAAIKAMP; Ionica SMEETS

    2011-01-01

    In 2004,Tong found bounds for the approximation quality of a regular continued fraction convergent to a rational number,expressed in bounds for both the previous and next approximation.The authors sharpen his results with a geometric method and give both sharp upper and lower bounds.The asymptotic frequencies that these bounds occur are also calculated.

  19. Sharp Embeddings of Besov Spaces with Logarithmic Smoothness

    Gurka, P.; Opic, Bohumír

    2005-01-01

    Roč. 18, č. 1 (2005), s. 81-110 ISSN 1139-1138 R&D Projects: GA ČR(CZ) GA201/01/0333 Institutional research plan: CEZ:AV0Z10190503 Keywords : Besov spaces wirh logarithmic smoothness * Lorentz-Zygmund spaces * sharp embeddings Subject RIV: BA - General Mathematics

  20. Surface-Wave Pulse Routing around Sharp Right Angles

    Gao, Z.; Xu, H.; Gao, F.; Zhang, Y.; Luo, Y.; Zhang, B.

    2018-04-01

    Surface-plasmon polaritons (SPPs), or localized electromagnetic surface waves propagating on a metal-dielectric interface, are deemed promising information carriers for future subwavelength terahertz and optical photonic circuitry. However, surface waves fundamentally suffer from scattering loss when encountering sharp corners in routing and interconnection of photonic signals. Previous approaches enabling scattering-free surface-wave guidance around sharp corners are limited to either volumetric waveguide environments or extremely narrow bandwidth, being unable to guide a surface-wave pulse (SPP wave packet) on an on-chip platform. Here, in a surface-wave band-gap crystal implemented on a single metal surface, we demonstrate in time-domain routing a surface-wave pulse around multiple sharp right angles without perceptible scattering. Our work not only offers a solution to on-chip surface-wave pulse routing along an arbitrary path, but it also provides spatiotemporal information on the interplay between surface-wave pulses and sharp corners, both of which are desirable in developing high-performance large-scale integrated photonic circuits.

  1. [Overview of sharps injuries among health-care workers].

    Gopar-Nieto, Rodrigo; Juárez-Pérez, Cuauhtémoc Arturo; Cabello-López, Alejandro; Haro-García, Luis Cuauhtémoc; Aguilar-Madrid, Guadalupe

    2015-01-01

    Sharps injuries are one of the most frequent health-care related accidents. It is estimated globally that 35 million workers are at risk; in Mexico there is no data available for this type of injuries. They are associated with lack of training, instrument and procedure risk, fatigue and stress. The occupational distribution is nurses 45 %, technicians 20 %, doctors 20 % and maintenance workers 5 %. The most commonly associated procedures are injection, venipuncture, suture, and insertion and manipulation of IV catheters. Hepatitis B is the most commonly transmitted agent. Emotional distress is huge as well as the cost of prophylaxis and follow-up. More than half of the injuries are not notified. The most common reasons for not reporting are: the belief that the exposure has low risk of infection, the lack of knowledge of reporting systems and the assumption that it is difficult to notify. Many strategies have been created to reduce the incidence of sharps injuries, such as: identifying the risk of blood exposure, the creation of politics to minimize the risk, the education and training to create a safe workplace, the enhancing of the reporting system, the use of double-gloving and using safety-engineered sharps devices. In many countries these politics have reduced the incidence of sharps injuries as well as the economic burden.

  2. Sharp at any Age: Moho boundary thickness estimates along a trans-sect through 2 Ga of tectonic history.

    Servali, A.; Levin, V. L.; VanTongeren, J. A.

    2015-12-01

    In this study we evaluate crustal thickness and Moho sharpness beneath seismic stations in three different tectonic units of the North American continent: the Archean Superior Province, the Proterozoic Grenville Province, and the Paleozoic Appalachian Orogen. Our analysis involves two steps. First, for each site, we produce P-to-S receiver functions (RFs) organized by backazimuth and epicentral distance, and use them to identify the phase most likely representing a conversion from the Moho. Second, we construct averaged RFs for groups of telesismic events located in a similar geographic region, which we employ to examine shapes of Moho P-to-S converted phases in time series with maximum frequencies increasing from 0.25Hz to 2-3 Hz. At some sites we observe a progressive narrowing of a simple Moho converted phase with an increase in frequency, typical of a vertically instantaneous boundary, while at others the converted phase becomes progressively more complex, typical of a diffuse Moho. Thus, we adopt this difference in converted wave shape dependence on increasing frequency as a measure of Moho thickness. Our estimates of Moho thickness range from less than 300 m to over 2 km, with some locations showing evidence for multiple converting boundaries in the 35-50 km depth range. In this study we define "sharp" Moho at those sites where its vertical thickness is less than 1 km. Our results show that sharp Moho is universal in the Archean terranes regardless of surface lithology, likely due to higher Moho temperatures facilitating wide-spread delamination of dense lower crustal rocks. While a sharp Moho is not unique to the Superior Province, all Grenville and Appalachians sites where we find sharp Moho are in regions of granitic plutonism, suggesting a possible general association with reworking and density sorting of the crustal material (e.g. volcanic arc).

  3. PRACTICES FOR PREVENTION NEEDLESTICK AND SHARPS INJURIES AMONG NURSING STUDENTS

    Anh Tran Thi Quynh

    2017-07-01

    Full Text Available Background: Needlestick and sharp injuries are a serious hazard in any health care setting for health care workers and students during clinical practice. Thus, the efforts to prevent the needlestick and sharps injuries are needed and considered a part of the routine practice. Objective: This study aimed to investigate the frequency of nursing students in doing the correct practice in prevention needlestick and sharps injuries. Methods: This cross- sectional study was conducted between 2013 and 2014 in nursing students of Tien Giang Medical College who participated in clinical practice. There were 360 students participated in the study using simple random sampling. Data were collected using the practical assessment checklist and demographic characteristics questionnaire. Data were processed using STATA 12.0, and analyzed using Chi-square and Fisher test. Results: The students who did general practice correctly accounted for 52.50%, and those who did practice incorrectly was 47.5%. The students who used gauze or wool wrap in inhaler were 59.7%, wearing gloves in practice (39.2%, do not disassemble needles from syringes after injection 50%, and removing needles into barrel after injection (65.6%. There was statistically significant relationship between time of participation in clinical practice and correct practice with p-value 0.04 (<0.05 Conclusion: The correct practice of nursing students related to the prevention of needlestick and sharps injuries remains low. There was a significant relationship between time of participation in clinical practice and correct nursing practice. It is suggested that students must be taught about the risk of infection at the beginning of clinical practice, and constantly reminded throughout the learning process, especially for injection safety awareness, knowledge and techniques about the risk of transmission of HBV, HCV and HIV by sharp objects in the healthcare facility.

  4. Myocardial perfusion imaging by digital subtraction angiography

    Kadowaki, Hiroyuki; Ishikawa, Kinji; Ogai, Toshihiro; Katori, Ryo

    1986-01-01

    Several methods of digital subtraction angiography (DSA) were compared to determine which could better visualize regional myocardial perfusion using coronary angiography in seven patients with myocardial infarction, two with angina pectoris and five with normal coronary arteries. Satisfactory DSA was judged to be achieved if the shape of the heart on the mask film was identical to that on the live film and if both films were exactly superimposed. To obtain an identical mask film in the shape of each live film, both films were selected from the following three phases of the cardiac cycle; 1) at the R wave of the electrocardiogram, 2) 100 msec before the R wave, and 3) 200 msec before the R wave. The last two were superior for obtaining mask and live films which were similar in shape, because the cardiac motion in these phases was relatively small. Using these mask and live films, DSA was performed either with the continuous image mode (CI mode) or the time interval difference mode (TID mode). The overall perfusion of contrast medium through the artery to the vein was adequately visualized using the CI mode. Passage of contrast medium through the artery, capillary and vein was visualized at each phase using TID mode. Subtracted images were displayed and photographed, and the density of the contrast medium was adequate to display contour lines as in a relief map. Using this DSA, it was found that regional perfusion of the contrast medium was not always uniform in normal subjects, depending on the typography of the coronary artery. In all patients with anterior myocardial infarction, low perfusion was observed at the infarcted portion compared to the non-infarcted myocardium. In patients with inferior myocardial infarction, this low perfusion area was not observed because right coronary angiography was not subjected to DSA in this study. (J.P.N.)

  5. Melatonin protects against myocardial hypertrophy induced by lipopolysaccharide.

    Lu, Qi; Yi, Xin; Cheng, Xiang; Sun, Xiaohui; Yang, Xiangjun

    2015-04-01

    Melatonin is thought to have the ability of antiatherogenic, antioxidant, and vasodilatory. It is not only a promising protective in acute myocardial infarction but is also a useful tool in the treatment of pathological remodeling. However, its role in myocardial hypertrophy remains unclear. In this study, we investigated the protective effects of melatonin on myocardial hypertrophy induced by lipopolysaccharide (LPS) and to identify their precise mechanisms. The cultured myocardial cell was divided into six groups: control group, LPS group, LPS + ethanol (4%), LPS + melatonin (1.5 mg/ml) group, LPS + melatonin (3 mg/ml) group, and LPS + melatonin (6 mg/ml) group. The morphologic change of myocardial cell was observed by inverted phase contrast microscope. The protein level of myocardial cell was measured by Coomassie brilliant blue protein kit. The secretion level of tumor necrosis factor-α (TNF-α) was evaluated by enzyme-linked immunosorbent assay (ELISA). Ca(2+) transient in Fura-2/AM-loaded cells was measured by Till image system. The expression of Ca(2+)/calmodulin-dependent kinase II (CaMKII) and calcineurin (CaN) was measured by Western blot analysis. Our data demonstrated that LPS induced myocardial hypertrophy, promoted the secretion levels of TNF-α, and increased Ca(2+) transient level and the expression of CaMKII and CaN. Administration of melatonin 30 min prior to LPS stimulation dose-dependently attenuated myocardial hypertrophy. In conclusion, the results revealed that melatonin had the potential to protect against myocardial hypertrophy induced by LPS in vitro through downregulation of the TNF-α expression and retains the intracellular Ca(2+) homeostasis.

  6. Abnormal myocardial capillary density in apical hypertrophic cardiomyopathy can be assessed by myocardial contrast echocardiography

    Moon, Jeonggeun; Cho, In-Jeong; Shim, Chi-Young; Ha, Jong-Won; Jang, Yangsoo; Chung, Namsik; Rim, Se-Joong

    2010-01-01

    Myocardial ischemia and dysfunction can occur in hypertrophic cardiomyopathy (HCM) because of the high muscle-to-blood ratio, even without significant coronary artery disease. Microbubbles reside only in the intravascular space and myocardial video-intensity during systole results mostly from microbubbles within capillaries. The hypothesis explored in the present study was that an abnormal capillary density in apical HCM (ApHCM) can be demonstrated using myocardial contrast echocardiography (MCE). The 56 patients were investigated (31 males, age 58±9 years; 33 ApHCM, 9 hypertensive left ventricular hypertrophy [LVH], 14 controls). MCE was performed with low-mechanical-index power modulation imaging. Tissue Doppler imaging to assess myocardial contractile function was obtained at the mitral annulus (S'), and 99m Tc-MIBI single photon emission computed tomography (SPECT) was also performed. All ApHCM patients exhibited perfusion defects at the hypertrophied segments in the systolic phase during MCE, whereas SPECT showed normal or rather increased perfusion at those sites. The cyclic variation of video-intensity was exaggerated in ApHCM when compared with the LVH or control group (% of [systolic video-intensity]/[diastolic video-intensity]: 33.0±12.3%, 88.3±19.2% and 79.4±13.9%, respectively [P<0.05]). Concurrently, MCE cyclic variation and perfusion defect size were related to decreased S' (P<0.05 for all). A perfusion defect at the hypertrophied segment, representing abnormal myocardial capillary density, was observed in ApHCM patients during MCE. The extent of MCE cyclic variation and the perfusion defect size both correlate with decreased myocardial contractile property in ApHCM. (author)

  7. Myocardial delayed-enhancement CT: initial experience in children and young adults

    Goo, Hyun Woo [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul (Korea, Republic of)

    2017-10-15

    Clinical utility of myocardial delayed enhancement CT has not been reported in children and young adults. To describe initial experience of myocardial delayed enhancement CT regarding image quality, radiation dose and identification of myocardial lesions in children and young adults. Between August 2013 and November 2016, 29 consecutive children and young adults (median age 16 months) with suspected coronary artery or myocardial abnormality underwent arterial- and delayed-phase cardiac CT at our institution. We measured CT densities in normal myocardium, left ventricular cavity, and arterial and delayed hypo-enhancing and delayed hyperenhancing myocardial lesions. We then compared the extent of delayed hyperenhancing lesions with delayed-enhancement MRI or thallium single-photon emission CT. Normal myocardium and left ventricular cavity showed significantly higher CT numbers on arterial-phase CT than on delayed-phase CT (t-test, P<0.0001). Contrast-to-noise ratios of the arterial and delayed hypo-enhancing and delayed hyperenhancing lesions on CT were 26.7, 17.6 and 18.7, respectively. Delayed-phase CT findings were equivalent to those of delayed-enhancement MRI in all cases (7/7) and to those of thallium single-photon emission CT in 70% (7/10). Myocardial delayed-enhancement CT can be added to evaluate myocardial lesions in select children and young adults with suspected coronary artery or myocardial abnormality. (orig.)

  8. Myocardial delayed-enhancement CT: initial experience in children and young adults

    Goo, Hyun Woo

    2017-01-01

    Clinical utility of myocardial delayed enhancement CT has not been reported in children and young adults. To describe initial experience of myocardial delayed enhancement CT regarding image quality, radiation dose and identification of myocardial lesions in children and young adults. Between August 2013 and November 2016, 29 consecutive children and young adults (median age 16 months) with suspected coronary artery or myocardial abnormality underwent arterial- and delayed-phase cardiac CT at our institution. We measured CT densities in normal myocardium, left ventricular cavity, and arterial and delayed hypo-enhancing and delayed hyperenhancing myocardial lesions. We then compared the extent of delayed hyperenhancing lesions with delayed-enhancement MRI or thallium single-photon emission CT. Normal myocardium and left ventricular cavity showed significantly higher CT numbers on arterial-phase CT than on delayed-phase CT (t-test, P<0.0001). Contrast-to-noise ratios of the arterial and delayed hypo-enhancing and delayed hyperenhancing lesions on CT were 26.7, 17.6 and 18.7, respectively. Delayed-phase CT findings were equivalent to those of delayed-enhancement MRI in all cases (7/7) and to those of thallium single-photon emission CT in 70% (7/10). Myocardial delayed-enhancement CT can be added to evaluate myocardial lesions in select children and young adults with suspected coronary artery or myocardial abnormality. (orig.)

  9. Improving acute and long-term myocardial infarction care : bridging the gap between science and practice

    Liem, Su-San

    2009-01-01

    The main topic of this thesis was the design, implementation and subsequent evaluation of an all-phases integrated care program for patients with acute myocardial infarction: the MISSION! protocol. The aim of MISSION! was to improve daily care for patients with an acute myocardial infarction by

  10. Acute myocardial infarction

    RISCHPLER, Christoph

    2016-01-01

    Inflammatory processes after myocardial infarction have gained major interest in recent cardiovascular research. It is believed that not only the degree of cell recruitment to the heart plays a pivotal role in the quality of wound healing after myocardial infarction, but also the balance between different types or even subtypes of cells. It is also this balance which is thought to control key processes in tissue repair, such as apoptosis and neoangiogenesis. In this paper, we aim to review imaging strategies (with a special focus on nuclear molecular imaging strategies) that target cells and processes involved in postischemic inflammation and that have a high potential to be translated into clinic or that are already being used and evaluated in humans.

  11. Thallium-201 myocardial imaging

    Wackers, F.J.Th.

    1980-01-01

    Three views are routinely obtained for 201 Tl scintigraphy: 0 0 anterior, 45 0 left-anterior-oblique, both views with the patient supine and a left-lateral view, with the patient lying on his right side. Following intravenous injection of 201 Tl, the scintiscans of a normal subject only demonstrate the left ventricle. In patients with normal myocardial perfusion, the left ventricle appears horseshoe or ovoid in shape. The central area of decreased activity represents the left ventricular cavity and is normal. The accumulation of 201 Tl in the normal left ventricle is usually homogeneous. However, some areas with apparent diminished uptake may occur in the normal subject. These variations of the normal image are discussed. The right ventricle, because of its smaller myocardial mass and relatively less 201 Tl accumulation per gram of tissue, is usually on a resting study not, or only faintly, visualized. However, following exercise, the right ventricle is clearly visualized. (Auth.)

  12. Energy dissipation characteristics of sharp-edged orifice plate

    Ai Wanzheng

    2015-08-01

    Full Text Available The energy loss coefficient, relating directly to the energy dissipation ratio, is an important index of this energy dissipater. In this article, this coefficient and its affecting parameters were analyzed by theoretical considerations, and their relationships were obtained by numerical simulations. It could be concluded that the energy loss coefficient of sharp-edged orifice plate and its backflow region length were mainly dominated by the contraction ratio of the orifice plate. Sharp-edged orifice plate’s energy loss coefficient and its backflow region length all increase slightly with the increase in its thickness. When Reynolds number is in the range of 9.00×104–10.3×106, Reynolds number has little impacts on energy loss coefficient and backflow region length. Two empirical expressions, relating to backflow region length and energy loss coefficient, respectively, were presented.

  13. Sharp bounds for periodic solutions of Lipschitzian differential equations

    Zevin, A A

    2009-01-01

    A general system of Lipschitzian differential equations, containing simultaneously terms without delay and with arbitrary constant and time-varying delays, is considered. For the autonomous case, a lower bound for the period of nonconstant periodic solutions, expressed in the respective supremum Lipschitz constants, is found. For nonautonomous periodic equations, explicit upper bounds for the amplitudes and maximum derivatives of periodic solutions are obtained. For all n ≥ 2, the bounds do not depend on n and, in general, are different from that for n = 1. All the bounds are sharp; they are attained in linear differential equations with piece-wise constant deviating arguments. A relation between the obtained bounds and the sharp bounds in other metrics is established

  14. Cryogenic receiver front-end with sharp skirt characteristics

    Narahashi, S [RF Technology Laboratory, Wireless Laboratories, NTT DoCoMo, Inc, Yokosuka, Kanagawa 239-8536 (Japan); Satoh, K [RF Technology Laboratory, Wireless Laboratories, NTT DoCoMo, Inc, Yokosuka, Kanagawa 239-8536 (Japan); Kawai, K [RF Technology Laboratory, Wireless Laboratories, NTT DoCoMo, Inc, Yokosuka, Kanagawa 239-8536 (Japan); Koizumi, D [RF Technology Laboratory, Wireless Laboratories, NTT DoCoMo, Inc, Yokosuka, Kanagawa 239-8536 (Japan); Nojima, T [Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Hokkaido 060-0808 (Japan)

    2006-05-15

    This paper presents an experimental cryogenic receiver front-end (CRFE) with sharp skirt characteristics for mobile base stations. The CRFE comprises a high-temperature superconducting filter, a cryogenic low-noise amplifier, and a highly reliable cryostat that is very compact. The major characteristics of the proposed CRFE measured at 70 K are a centre frequency of 1.95 GHz, passband width of 20 MHz, sharp selectivity of 20 dB/100 kHz, 1.4 dB ripple, 31.3 dB average passband gain, and average passband equivalent noise temperature of 47.9 K. The CRFE weighs 19 kg and occupies 35 l. Random failure of the cryostat is also evaluated by a continuous operation test using four identical ones simultaneously. The cryostat used in the CRFE has a high reliability level of over five years of continuous maintenance-free operation.

  15. Anomalous optical behavior of biological media: modifying the optical window of myocardial tissues

    Splinter, Robert; Raja, M. Yasin A.; Svenson, Robert H.

    1996-05-01

    In medical experimental and clinical treatment modalities of light, laser photocoagulation of ventricular tachycardia amongst others, the success of the application relies on whether or not the procedure operates in the optical window of the light-tissue interaction. The optical window of biological tissues can be determined by spectral scans of the optical properties. Optical anomalies may result from the irradiance, the wavelength, or from the tissue composition itself. The transmission of cw Nd:YAG laser light on myocardial tissue showed a nonlinearity in the transmission curve at approximately 3 kW/mm2 irradiance. The total attenuation coefficient dropped sharp from 1.03 plus or minus 0.04 mm-1 to 0.73 plus or minus 0.05 mm-1 at this point in the curve. On the other hand, aneurysm tissue has a highly organized fiber structure, which serves as light-guides, since the transmission of light along the length of the collagen fibers is approximately 50% higher than the transmission perpendicular to the fiber orientation. In addition, changes in optical properties due to tissue phase changes also influence the penetration depth. These phenomena can be utilized to manipulate the optical penetration to an advantage.

  16. A Constructive Sharp Approach to Functional Quantization of Stochastic Processes

    Junglen, Stefan; Luschgy, Harald

    2010-01-01

    We present a constructive approach to the functional quantization problem of stochastic processes, with an emphasis on Gaussian processes. The approach is constructive, since we reduce the infinite-dimensional functional quantization problem to a finite-dimensional quantization problem that can be solved numerically. Our approach achieves the sharp rate of the minimal quantization error and can be used to quantize the path space for Gaussian processes and also, for example, Lévy processes.

  17. Treatment of sharp mandibular alveolar process with hybrid prosthesis

    Sukaedi, Sukaedi; Djulaeha, Eha

    2010-01-01

    Background: Losing posterior teeth for a long time would occasionally lead to the sharpening of alveolar process. The removable partial denture usually have problems when used during mastication, because of the pressure on the mucosa under the alveolar ridge. Purpose: The purpose of this case report was to manage patients with sharp mandibular alveolar process by wearing hybrid prosthesis with extra coronal precision attachment retention and soft liner on the surface base beneath the removabl...

  18. Sharp Dissection versus Electrocautery for Radial Artery Harvesting

    Marzban, Mehrab; Arya, Reza; Mandegar, Mohammad Hossein; Karimi, Abbas Ali; Abbasi, Kiomars; Movahed, Namvar; Abbasi, Seyed Hesameddin

    2006-01-01

    Radial arteries have been increasingly used during the last decade as conduits for coronary artery revascularization. Although various harvesting techniques have been described, there has been little comparative study of arterial damage and patency. A radial artery graft was used in 44 consecutive patients, who were randomly divided into 2 groups. In the 1st group, the radial artery was harvested by sharp dissection and in the 2nd, by electrocautery. These groups were compared with regard to radial artery free flow, harvest time, number of clips used, complications, and endothelial damage. Radial artery free flow before and after intraluminal administration of papaverine was significantly greater in the electrocautery group (84.3 ± 50.7 mL/min and 109.7 ± 68.5 mL/min) than in the sharp-dissection group (52.9 ± 18.3 mL/min and 69.6 ± 28.2 mL/ min) (P =0.003). Harvesting time by electrocautery was significantly shorter (25.4 ± 4.3 min vs 34.4 ± 5.9 min) (P =0.0001). Electrocautery consumed an average of 9.76 clips, versus 22.45 clips consumed by sharp dissection. The 2 groups were not different regarding postoperative complications, except for 3 cases of temporary paresthesia of the thumb in the electrocautery group; histopathologic examination found no endothelial damage. We conclude that radial artery harvesting by electrocautery is faster and more economical than harvesting by sharp dissection and is associated with better intraoperative flow and good preservation of endothelial integrity. PMID:16572861

  19. Myocardial ischemia in hypertrophic cardiomyopathy

    Lima Filho, Moyses de Oliveira; Figueiredo, Geraldo L.; Simoes, Marcus V.; Pyntia, Antonio O.; Marin Neto, Jose Antonio

    2000-01-01

    Myocardial ischemia in hypertrophic cardiomyopathy is multifactorial and explains the occurrence of angina, in about 50% of patients. The pathophysiology of myocardial ischemia may be explained by the increase of the ventricular mass and relative paucity of the coronary microcirculation; the elevated ventricular filling pressures and myocardial stiffness causing a compression of the coronary microvessels; the impaired coronary vasodilator flow reserve caused by anatomic and functional abnormalities; and the systolic compression of epicardial vessel (myocardial bridges). Myocardial ischemia must be investigated by perfusion scintigraphic methods since its presence influences the prognosis and has relevant clinical implications for management of patients. Patients with hypertrophic cardiomyopathy and documented myocardial ischemia usually need to undergo invasive coronary angiography to exclude the presence of concomitant atherosclerotic coronary disease. (author)

  20. Acute myocardial infarcts

    Just, H.

    1988-01-01

    Acute myocardial infarction is a major complication of stenosing coronary artery disease and constitutes the most frequent single cause of death. It is caused by thrombotic occlusion of one of the major epicardial coronary arterial branches in most cases. Sudden death due to ventricular fibrillation is responsible for the majority of early fatalities. In 60% of all fatal infarcts, death occurs within 1 h of the onset of pain. The final extension of myocardial necrosis is reached within 2-4 h. An integrated programme has therefore been developed for the supervision and treatment of patients suffering acute coronary attack; it has been shown that it can markedly lower infarct mortality. It includes mobile prehospital care, intensive care treatment in the hospital, and rehabilitative procedures for application during reconvalescence. Early antiarrhythmic treatment and myocardial reperfusion via fibrinolysis are the main therapeutic procedures in the earliest stage. In hospital an operating room and an operating team must be available round the clock for the performance of coronary angiography followed by percutaneous transluminal coronary angioplasty or bypass surgery, which can be safely carried out in the acute stage provided the indications are strictly observed. Mortality and morbidity can be significantly lowered and both life expectancy and quality of life can be remarkably improved. (orig.) [de

  1. Needlestick and Sharp Instruments Injuries among Brazilian Dentistry Students

    Fernandes, Liege Helena Freitas; Nunes, Wanúbia Barbosa; Silva, Larissa Costa; Wanderley, Rayssa Lucena; Barros, Criseuda Maria Benício; Cavalcanti, Alessandro Leite

    2017-01-01

    Background: The occurrence of occupational accidents is common among students and dentists. The present study is aimed to evaluate the prevalence and characteristics of needlestick and sharp instrument injuries among dentistry students. Materials and Methods: A documentary research was carried out with data being obtained from the analysis of 137 medical records of injuries caused by needlestick and sharp instruments occurring in the period from 2012 to 2016 and were analyzed regarding the characteristics of the victim (gender and age) and the accident (year, time, environment, and time interval between exposure and search for care). Data were organized in the Statistical Package for Social Sciences software version 18 and were presented through descriptive statistics. Results: The occurrence of accidents was high (43.1%), with the predominance of female victims (66.1%) and aged up to 23 years (55.9%). The majority of events occurred in the afternoon (54.4%), in the clinical setting (70.7%), and in 75% of the cases, the search for care occurred within 2 h after exposure. Conclusion: Accidents with needlestick and sharp instruments have high frequency and involve mainly female students. They are more common in the afternoon and in the clinical setting and the time interval was between exposure and the search for care complied with recommendations of the Brazilian legislation. PMID:28566861

  2. SHARP - a framework for incorporating human interactions into PRA studies

    Hannaman, G.W.; Joksimovich, V.; Spurgin, A.J.; Worledge, D.H.

    1985-01-01

    Recently, increased attention has been given to understanding the role of humans in the safe operation of nuclear power plants. By virtue of the ability to combine equipment reliability with human reliability probabilistic risk assessment (PRA) technology was deemed capable of providing significant insights about the contributions of human interations in accident scenarios. EPRI recognized the need to strengthen the methodology for incorporating human interactions into PRAs as one element of their broad research program to improve the credibility of PRAs. This research project lead to the development and detailed description of SHARP (Systematic Human Application Reliability Procedure) in EPRI NP-3583. The objective of this paper is to illustrate the SHARP framework. This should help PRA analysts state more clearly their assumptions and approach no matter which human reliability assessment technique is used. SHARP includes a structure of seven analysis steps which can be formally or informally performed during PRAs. The seven steps are termed definition, screening, breakdown, representation, impact assessment, quantification, and documentation

  3. Weighting of field heights for sharpness and noisiness

    Keelan, Brian W.; Jin, Elaine W.

    2009-01-01

    Weighting of field heights is important in cases when a single numerical value needs to be calculated that characterizes an attribute's overall impact on perceived image quality. In this paper we report an observer study to derive the weighting of field heights for sharpness and noisiness. One-hundred-forty images were selected to represent a typical consumer photo space distribution. Fifty-three sample points were sampled per image, representing field heights of 0, 14, 32, 42, 51, 58, 71, 76, 86% and 100%. Six observers participated in this study. The field weights derived in this report include both: the effect of area versus field height (which is a purely objective, geometric factor); and the effect of the spatial distribution of image content that draws attention to or masks each of these image structure attributes. The results show that relative to the geometrical area weights, sharpness weights were skewed to lower field heights, because sharpness-critical subject matter was often positioned relatively near the center of an image. Conversely, because noise can be masked by signal, noisiness-critical content (such as blue skies, skin tones, walls, etc.) tended to occur farther from the center of an image, causing the weights to be skewed to higher field heights.

  4. SHARP1: A revised systematic human action reliability procedure

    Wakefield, D.J.; Parry, G.W.; Hannaman, G.W.; Spurgin, A.J.

    1990-12-01

    Individual plant examinations (IPE) are being performed by utilities to evaluate plant-specific vulnerabilities to severe accidents. A major tool in performing an IPE is a probabilistic risk assessment (PRA). The importance of human interactions in determining the plant response in past PRAs is well documented. The modeling and quantification of the probabilities of human interactions have been the subjects of considerable research by the Electric Power Research Institute (EPRI). A revised framework, SHARP1, for incorporating human interactions into PRA is summarized in this report. SHARP1 emphasizes that the process stages are iterative and directed at specific goals rather than being performed sequentially in a stepwise procedure. This expanded summary provides the reader with a flavor of the full report content. Excerpts from the full report are presented, following the same outline as the full report. In the full report, the interface of the human reliability analysis with the plant logic model development in a PRA is given special attention. In addition to describing a methodology framework, the report also discusses the types of human interactions to be evaluated, and how to formulate a project team to perform the human reliability analysis. A concise description and comparative evaluation of the selected existing methods of quantification of human error are also presented. Four case studies are also provided to illustrate the SHARP1 process

  5. Deciphering the role of CA1 inhibitory circuits in sharp wave-ripple complexes.

    Cutsuridis, Vassilis; Taxidis, Jiannis

    2013-01-01

    Sharp wave-ripples (SWRs) are population oscillatory patterns in hippocampal LFPs during deep sleep and immobility, involved in the replay of memories acquired during wakefulness. SWRs have been extensively studied, but their exact generation mechanism is still unknown. A computational model has suggested that fast perisomatic inhibition may generate the high frequency ripples (~200 Hz). Another model showed how replay of memories can be controlled by various classes of inhibitory interneurons targeting specific parts of pyramidal cells (PC) and firing at particular SWR phases. Optogenetic studies revealed new roles for interneuronal classes and rich dynamic interplays between them, shedding new light in their potential role in SWRs. Here, we integrate these findings in a conceptual model of how dendritic and somatic inhibition may collectively contribute to the SWR generation. We suggest that sharp wave excitation and basket cell (BC) recurrent inhibition synchronises BC spiking in ripple frequencies. This rhythm is imposed on bistratified cells which prevent pyramidal bursting. Axo-axonic and stratum lacunosum/moleculare interneurons are silenced by inhibitory inputs originating in the medial septum. PCs receiving rippling inhibition in both dendritic and perisomatic areas and excitation in their apical dendrites, exhibit sparse ripple phase-locked spiking.

  6. Wall motion abnormality of myocardial infarction

    Hayashi, Senji; Tsuda, Takashi; Ojima, Kenji

    1984-01-01

    By use of the gated blood pool scan, we divided the left ventricular LAO 45 image into 8 sections with the center of the volume as the basal point, and devised a method of quantitative evaluation of the regional wall motion from 2 aspects: 1) wall movement and 2) phase abnormality. To evaluate the wall movement, we obtained the following indeces from count curves of each section: 1) EF1=(end-diastolic count-end-systolic count)/ end-diastolic count, 2) EF2=(maximum count-minimum count)/maximum count, and 3) the difference of the two (EF2-EF1). As indeces of the phase abnormality, the mean value of phases of the pixels (phase characteristics) and the standard deviation (variation) of each section were calculated. Furthermore, the phase delay of each section was calculated as the difference from the earliest phase value of the 8 sections. Control values and standard deviation were obtained from 8 healthy controls. By this method, we analyzed 20 patients with old myocardial infarction. And following results were obtained: 1. Applying this method, we could evaluate the regional wall motion of the left ventricle more precisely, and we considered it would be useful clinically. 2. The abnormal regional wall motion of old myocardial infarction were classified into 4 typical forms as follows: 1) the wall movement decreased extremely. 2) the wall movement decreased, but no phase delay recognized. 3) the wall movement did not decrease, but phase delay was recognized. 4) the wall movement decreased, and phase delay was recognized. (author)

  7. Equilibrium radionuclide ventriculography in male patients after transmural myocardial infarction

    Nestaval, A; Stanek, V; Malek, I; Kidery, J; Runczik, I [Institut pro Klinickou a Experimentalni Medicinu, Prague (Czechoslovakia); Cernoch, V; Oppelt, A [Institut pro Dalsi Vzdelavani Lekaru a Farmaceutu, Prague (Czechoslovakia)

    1982-12-17

    The ejection fraction of the left ventricle was measured using the method of equilibrium radionuclide ventriculography in 10 healthy males and 57 males after the first transmural myocardial infarction. The examination was effected 4 to 7 months after the event and the sample is representative for males after myocardial infarction who are younger than 65 years and show no signs of heart insufficiency by the time of examination. The resting value of the ejection fraction was 63+-5% in healthy males, 54+-7% in patients with uncomplicated myocardial infarction and 37+-8% in patients with clinical manifestations of heart insufficiency in acute phase. The differences between the groups are statistically significant. In patients with anteroseptal localization of myocardial infarction there was a negative correlation between the ejection fraction on the one hand and the sum of the voltages of Q waves in precordial ECG map and the maximum value of serum creatine kinase in acute phase on the other. The ejection fraction was in correlation to the degree of pulmonary hypertension measured in equal phase during exercise. The ejection fraction was measured in 31 patients under the working load of 50 W; significant changes were not found in healthy males or in patients after myocardial infarction. No changes were found when the state just before discharge from the hospital was compared with his state 6 months after myocardial infarction. The results obtained in compensated patients showed a relative stability of the value of the ejection fraction both during the first 6 months after discharge and under a mild working load. A comparison between the indicators in acute phase and hemodynamic examination after 6 months shows that the value of the ejection fraction is a sensitive indicator of the extent of necrosis and functional lesion of the left ventricle.

  8. Characterization of Organic Materials in the Xenolithic Clasts in Sharps (H3.4) Meteorite Using Micro-Raman Spectroscopy

    Chan, Q. H. S.; Zolensky, M. E.; Bodnar, R. J.; Kebukawa, Y.

    2015-01-01

    Graphitization of carbon is an irreversible process which alters the structure of graphitic materials in response to the increase in metamorphic grade (temperature and/or pressure). Carbonaceous materials offer a reliable geothermometer as their Raman spectra change systematically with increasing metamorphic grade. In this study, we identified carbonaceous materials in the xenolithic clasts in Sharps and interpreted their metamorphic history by revealing the structural organization (order) of the polyaromatic organic phases using micro-Raman spectroscopy.

  9. Characterization of Organic Materials in the Xenolithic Clasts in Sharps (H3.4) Meteorite Using Microraman Spectroscopy

    Chan, Q. H. S.; Zolensky, M. E.; Bodnar, R. J.; Kebukawa, Y.

    2015-01-01

    Graphitization of carbon is an irreversible process which alters the structure of graphitic materials in response to the increase in metamorphic grade (temperature and/or pressure). Carbonaceous materials offer a reliable geothermometer as their Raman spectra change systematically with increasing metamorphic grade [1-3]. In this study, we identified carbonaceous materials in the xenolithic clasts in Sharps and interpreted their metamorphic history by revealing the structural organization (order) of the polyaromatic organic phases using µ-Raman spectroscopy.

  10. Analysis and protective measures of sharp instrument injury causes of sterilization and supply center

    Hua YANG

    2014-11-01

    Full Text Available Objective: To analyze the causes of sharp injury in the sterilization and supply center, take protective measures, effectively avoid sharp instrument injury, and guarantee staff safety. Methods: Adopt a retrospective survey method, summarize sharp instrument injury data of sterilization and supply center in 2013, analyze the reasons of the occurrence of sharp instrument injury, and make protective countermeasures. Results: Sharp instrument injuries occurred mainly in the device classification, manual cleaning and device packaging process. Conclusion: Poor consciousness of occupational protection of the staff in the sterilization and supply center, nonstandard operation, and lack of training and supervision in place are the main reasons of occurrence of sharp instrument injury.

  11. Importance of layer thermal conductivity on the sharpness of patterns produced by laser interference

    Peláez, R.J., E-mail: rpelaez@io.cfmac.csic.es [Laser Processing Group, Instituto de Optica, CSIC, Serrano 121, 28006 Madrid (Spain); Afonso, C.N. [Laser Processing Group, Instituto de Optica, CSIC, Serrano 121, 28006 Madrid (Spain); Škereň, M. [Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Brehova 7, 115 19 Prague 1 (Czech Republic); Bulíř, J. [Institute of Physics, ASCR, v.v.i., Na Slovance 2, Prague (Czech Republic)

    2016-06-30

    Highlights: • Temperature profile matches laser intensity profile in poor thermally conducting layers. • Patterns produced in poor thermally conducting layers have sharp interfaces. • Lateral heat flow smears the temperature profile in thermally conducting layers. • Both liquid and solid state dewetting occurs upon patterning thermally conducting layers. • The thermal conductivity of layers limits the minimum period achievable. - Abstract: In this work, we compare patterns produced in Ag layers having similar thickness in the range 8.3–10.8 nm but having different initial nanostructure, i.e. behaving either as discontinuous or continuous layers and thus having very different thermal conductivities. The patterns are produced by exposing a phase mask to an excimer laser operating at 193 nm and using a projection optics that leads to similar fringed patterns with periods in the range 6.3–6.7 μm. The layer breaks up into isolated NPs due to laser induced melting at the regions around the intensity maxima sites. The resulting fringes have sharp interfaces in the case of discontinuous layers while a variety of regions across the pattern with no sharp interfaces are produced in the case of continuous layers. The results show that while the temperature distribution across the pattern matches almost perfectly the laser beam intensity profile for the former case, it becomes smeared due to lateral heat flow for the latter case. These results provide evidences for significant heating at the intensity minima sites that lead to solid-state dewetting and will eventually limit the minimum period achievable in the case of continuous metal layers or thermally conducting layers.

  12. Temporal Modulation Detection Depends on Sharpness of Spatial Tuning.

    Zhou, Ning; Cadmus, Matthew; Dong, Lixue; Mathews, Juliana

    2018-04-25

    Prior research has shown that in electrical hearing, cochlear implant (CI) users' speech recognition performance is related in part to their ability to detect temporal modulation (i.e., modulation sensitivity). Previous studies have also shown better speech recognition when selectively stimulating sites with good modulation sensitivity rather than all stimulation sites. Site selection based on channel interaction measures, such as those using imaging or psychophysical estimates of spread of neural excitation, has also been shown to improve speech recognition. This led to the question of whether temporal modulation sensitivity and spatial selectivity of neural excitation are two related variables. In the present study, CI users' modulation sensitivity was compared for sites with relatively broad or narrow neural excitation patterns. This was achieved by measuring temporal modulation detection thresholds (MDTs) at stimulation sites that were significantly different in their sharpness of the psychophysical spatial tuning curves (PTCs) and measuring MDTs at the same sites in monopolar (MP) and bipolar (BP) stimulation modes. Nine postlingually deafened subjects implanted with Cochlear Nucleus® device took part in the study. Results showed a significant correlation between the sharpness of PTCs and MDTs, indicating that modulation detection benefits from a more spatially restricted neural activation pattern. There was a significant interaction between stimulation site and mode. That is, using BP stimulation only improved MDTs at stimulation sites with broad PTCs but had no effect or sometimes a detrimental effect on MDTs at stimulation sites with sharp PTCs. This interaction could suggest that a criterion number of nerve fibers is needed to achieve optimal temporal resolution, and, to achieve optimized speech recognition outcomes, individualized selection of site-specific current focusing strategies may be necessary. These results also suggest that the removal of

  13. Investigation of Sharp Injuries in an Educational Hospital, Ahvaz, Iran

    Sahar Geravandi

    2017-01-01

    Full Text Available Background & Aims of the Study: The Sharp Injuries (SIs are a percutaneous piercing wound caused by a sharp instrument. Needle Sticks and Sharp Injuries (NSSIs can increase the incidence of cases of Hepatitis B, C and HIV. The purpose of this study was to Investigation of the relative frequency of NSSIs in healthcare workers (HCWs in Ahvaz, Iran (Razi hospital over 3-year period (2011–2013. Materials and Methods: A descriptive study during 2011-2013 was conducted on 600 HCWs at Razi Hospital, Ahvaz, Iran. To measure NSSIs, has been diagnosis and categorized based on the National Nosocomial Infections Surveillance (NNIS. Data about health workers’ age, sex, site of NSIs injury, ward of hospitalization and case of needle stick were collected. Descriptive statistical by SPSS version 16 used for analyzed data in this study. Results: According to the results of this study, among all nurses, the maximum cases of NSIs were HCWs. Regarding the finding, recapping needle were found in 34.17%, handling needle in 20.25%, suturing in 16.45%, passing needle in 13.92%, transit disposal in 8.86% and dissembling needle in 6.32% of cases. Findings showed that the most NSIs in Razi Hospital were general surgery, emergency, Intensive Care Unit (ICU, Obstetrics and Gynecology (OBGYN, operating room, orthopedic and infectious diseases wards during 2011-2013. Conclusion: Based on these findings, the number of health care-associated with NSIs between nurses in our study may be due to the shortage of nurses, long working hours during the night shift, fatigue and failure to use an appropriate equipment.

  14. SURGERY OF SYMPTOMATIC MYOCARDIAL BRIDGING

    N. Maghamipour N. Safaei

    2007-06-01

    Full Text Available Myocardial bridging with systolic compression of the left anterior descending coronary artery (LAD may be associated with myocardial ischemia. In symptomatic myocardial bridging unresponsive to medical treatment, surgical unroofing of the left LAD can be performed. Little information is available about the long-term prognosis of patients with this coronary anomaly after the surgical unroofing, so we decided to evaluate the result of this operation. A total of 26 patients underwent surgical unroofing of myocardial bridging. Patients had a myocardial bridge of at least 3 cm in length in the middle of LAD and with more than 70% compression during systole. Unroofing was performed with cardiopulmonary bypass in 16 and with off pump technique in 10 patients. In 6 patients repeat angiographies for control of myotomy were done. In one of them a nonsignificant 20% narrowing was seen. Postoperative scintigraphic and angiographic studies demonstrated restoration of coronary flow and myocardial perfusion without residual myocardial bridges under beta-stimulation in 24 patients. Two patients had residual narrowing. With off pump technique, 1 patient had perforation of the right ventricle and 1 patient underwent reoperation because of incomplete unroofing during the first operation. None of the patients with cardiopulmonary bypass technique had residual chest pain or other complications. Surgical unroofing of myocardial bridging with the aid of cardiopulmonary bypass is a safe and easy procedure with low operative risk and with excellent functional results.

  15. An Intersection–Union Test for the Sharpe Ratio

    Gabriel Frahm

    2018-04-01

    Full Text Available An intersection–union test for supporting the hypothesis that a given investment strategy is optimal among a set of alternatives is presented. It compares the Sharpe ratio of the benchmark with that of each other strategy. The intersection–union test takes serial dependence into account and does not presume that asset returns are multivariate normally distributed. An empirical study based on the G–7 countries demonstrates that it is hard to find significant results due to the lack of data, which confirms a general observation in empirical finance.

  16. On the sharpness of the Rüssmann estimates

    Figueras, Jordi-Lluís; Haro, Alex; Luque, Alejandro

    2018-02-01

    Estimating the norm of the solution of the linear difference equation u(θ) - u(θ + ω) = v(θ) plays a fundamental role in KAM theory. Optimal (in certain sense) estimates for the solution of this equation were provided by Rüssmann in the mid 70's. The aim of this paper is to compare the sharpness of these classical estimates with more specific estimates obtained with the help of the computer. We perform several experiments to quantify the improvement obtained when using computer assisted estimates. By comparing these estimates with the actual norm of the solution, we can analyze the different sources of overestimation, thus encouraging future improvements.

  17. DSMC simulations of shock interactions about sharp double cones

    Moss, James N.

    2001-08-01

    This paper presents the results of a numerical study of shock interactions resulting from Mach 10 flow about sharp double cones. Computations are made by using the direct simulation Monte Carlo (DSMC) method of Bird. The sensitivity and characteristics of the interactions are examined by varying flow conditions, model size, and configuration. The range of conditions investigated includes those for which experiments have been or will be performed in the ONERA R5Ch low-density wind tunnel and the Calspan-University of Buffalo Research Center (CUBRC) Large Energy National Shock (LENS) tunnel.

  18. Sharp metric obstructions for quasi-Einstein metrics

    Case, Jeffrey S.

    2013-02-01

    Using the tractor calculus to study smooth metric measure spaces, we adapt results of Gover and Nurowski to give sharp metric obstructions to the existence of quasi-Einstein metrics on suitably generic manifolds. We do this by introducing an analogue of the Weyl tractor W to the setting of smooth metric measure spaces. The obstructions we obtain can be realized as tensorial invariants which are polynomial in the Riemann curvature tensor and its divergence. By taking suitable limits of their tensorial forms, we then find obstructions to the existence of static potentials, generalizing to higher dimensions a result of Bartnik and Tod, and to the existence of potentials for gradient Ricci solitons.

  19. Optimizing 3D Triangulations to Recapture Sharp Edges

    Bærentzen, Jakob Andreas

    2006-01-01

    In this report, a technique for optimizing 3D triangulations is proposed. The method seeks to minimize an energy defined as a sum of energy terms for each edge in a triangle mesh. The main contribution is a novel per edge energy which strikes a balance between penalizing dihedral angle yet allowing...... sharp edges. The energy is minimized using edge swapping, and this can be done either in a greedy fashion or using simulated annealing. The latter is more costly, but effectively avoids local minima. The method has been used on a number of models. Particularly good results have been obtained on digital...

  20. Sharp Bounds by Probability-Generating Functions and Variable Drift

    Doerr, Benjamin; Fouz, Mahmoud; Witt, Carsten

    2011-01-01

    We introduce to the runtime analysis of evolutionary algorithms two powerful techniques: probability-generating functions and variable drift analysis. They are shown to provide a clean framework for proving sharp upper and lower bounds. As an application, we improve the results by Doerr et al....... (GECCO 2010) in several respects. First, the upper bound on the expected running time of the most successful quasirandom evolutionary algorithm for the OneMax function is improved from 1.28nln n to 0.982nlnn, which breaks the barrier of nln n posed by coupon-collector processes. Compared to the classical...

  1. Axisymmetric MHD stability of sharp-boundary Tokamaks

    Rebhan, E.; Salat, A.

    1976-09-01

    For a sharp-boundary, constant pressure plasma model of axisymmetric equilibria the MHD stability problem of axisymmetric perturbations is solved by analytic reduction to a one-dimensional problem on the boundary and subsequent numerical treatment, using the energy principle. The stability boundaries are determined for arbitrary aspect ratio, arbitrary βsub(p) and elliptical, triangular and rectangular plasma cross-sections, wall stabilization not being taken into account. It is found that the axisymmetric stability strongly depends on the plasma shape and is almost independent of the safety factor q. (orig.) [de

  2. Magnetic field penetration into superconductors with sharp edges

    Zhilichev, Yuriy N.

    2003-01-01

    The magnetic field and surface currents induced within a superconductor are calculated assuming the field penetrates in it near sharp corners. Rounding the corners is used to keep the field less than a critical value. Analytical formulas for a corner radius are given for a wire of the rectangular cross-section and a cylinder in the external magnetic field. A boundary integral method is used to calculate the boundary of the Meissner domain when the external field penetrates deep into the superconductor. The effect of degree of penetration on the magnetic moment of superconducting cylinders and wires is discussed

  3. Endovascular Sharp Recanalization for Calcified Femoropopliteal Artery Occlusion

    Hsuan-Li Huang

    2012-01-01

    Full Text Available Endovascular intervention of peripheral chronic total occlusion (CTO is technically challenging and time consuming. Various techniques and devices are used to facilitate lesion crossing and improve the success rate of the procedure. However, these new devices are quite expensive and not readily available. We report 2 cases of peripheral CTO wherein the occlusions were successfully crossed by using stiff end of Terumo glidewire. This sharp recanalization may be a useful technique for the recanalization of calcified peripheral CTOs when conventional techniques fail and new devices are not readily available, but it is accompanied by the risk of distal atheroembolism.

  4. The relationship between myocardial blood flow and myocardial viability after reperfusion. Myocardial viability assessed by [sup 15]O-water-PET

    Tsukagoshi, Joichi (Gunma Univ., Maebashi (Japan). School of Medicine)

    1994-09-01

    The purpose of this study was to examine the relationship between myocardial blood flow and myocardial viability in the ischemic canine myocardium after reperfusion. Transient ischemia was induced by 60-, 90-, and 180-minute occlusion of the left anterior descending coronary artery. Myocardial blood flow (MBF) was measured in the areas in which regional contractility was severely impaired (ehocardiographically akinetic or dyskinetic) in the early reperfusion period by [sup 15]O-water positron emission tomography (PET) 12 hours and 4 weeks after reperfusion. An MBF ratio of ischemic to nonischemic regions 12 hours after reperfusion was inversely correlated with the amount of histologically determined tissue necrosis (r=-0.74). The regional contractility recovered 4 weeks later in the areas where an MBF ratio was 0.48 or greater, but did not recover in the areas with a lower MBF ratio. Thus, myocardial viability can be appropriately predicted in the early phase of myocardial perfusion by PET with [sup 15]O-water even in the absence of metabolic imaging. (author).

  5. Hybridization between Dusky Grouse and Sharp-tailed Grouse

    O'Donnell, Ryan P.

    2015-01-01

    Cache County, Utah, 7 April 2013: rare hybrid combination of grouse noted. Hybridization between Dusky Grouse (Dendragapus obscurus) and Sharp-tailed Grouse (Tympanuchus phasianellus) has been rarely documented in the wild. The only published record was of one collected from Osoyoos, British Columbia, in 1906 (Brooks 1907, Lincoln 1950). There is also one record of this hybrid in captivity (McCarthy 2006)...Although hybridization within genera is more common than between genera, it is perhaps not all too remarkable that these species would hybridize, given that Dendragapus and Tympanuchus are each other’s closest relatives (Drovetski 2002). The ranges of these two species overlap over a broad area ranging roughly from parts of northern Utah and Colorado to Yukon and the Northwest Territories. Given the close relatedness and extent of overlap of their ranges, it is perhaps surprising that there have not been more reports of this hybrid combination in the over-100 years since Brooks (1907) first described one. The species may be segregated by habitat use, as Sharp-tailed prefer open grassland sites for lekking and shrub areas for nesting, and Dusky are often found in more densely forested conifer stands—although Dusky often use more open habitats in the spring.

  6. Sharp-tailed Grouse and Pygmy Rabbit Wildlife Mitigation Project

    1992-10-01

    The Proposed Action is needed to protect and enhance shrub-steppe and riparian habitat for sharp-tailed grouse (Tympanuchus phasianellus columbianus), Pygmy rabbits (Brachylagus idahoensis), and other indigenous wildlife species. The purpose of the Proposed Action is to compensate, in part, for wildlife habitat lost from the construction of Grand Coulee Dam and the inundation of Lake Roosevelt. Bonneville Power Administration proposes to fund management agreements, conservation easements, acquisition of fee title, or a combination of these on as many as 29,000 acres in Lincoln and Douglas Counties to improve shrub-steppe and riparian habitat for sharp-tailed grouse and pygmy rabbits. The BPA also proposes to fund habitat improvements (enhancements) on project lands including existing public lands. Proposed habitat treatments would include control of grazing; planting of native trees, shrubs, forbs and grasses; protection of wetlands and streambanks; herbicide use; fire prescriptions; and wildfire suppression. Proposed management activities may include predator control, population introductions, and control of crop depredation

  7. Consistency relations for sharp inflationary non-Gaussian features

    Mooij, Sander; Palma, Gonzalo A.; Panotopoulos, Grigoris [Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Blanco Encalada 2008, Santiago (Chile); Soto, Alex, E-mail: sander.mooij@ing.uchile.cl, E-mail: gpalmaquilod@ing.uchile.cl, E-mail: gpanotop@ing.uchile.cl, E-mail: gatogeno@gmail.com [Departamento de Física, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago (Chile)

    2016-09-01

    If cosmic inflation suffered tiny time-dependent deviations from the slow-roll regime, these would induce the existence of small scale-dependent features imprinted in the primordial spectra, with their shapes and sizes revealing information about the physics that produced them. Small sharp features could be suppressed at the level of the two-point correlation function, making them undetectable in the power spectrum, but could be amplified at the level of the three-point correlation function, offering us a window of opportunity to uncover them in the non-Gaussian bispectrum. In this article, we show that sharp features may be analyzed using only data coming from the three point correlation function parametrizing primordial non-Gaussianity. More precisely, we show that if features appear in a particular non-Gaussian triangle configuration (e.g. equilateral, folded, squeezed), these must reappear in every other configuration according to a specific relation allowing us to correlate features across the non-Gaussian bispectrum. As a result, we offer a method to study scale-dependent features generated during inflation that depends only on data coming from measurements of non-Gaussianity, allowing us to omit data from the power spectrum.

  8. Consistency relations for sharp inflationary non-Gaussian features

    Mooij, Sander; Palma, Gonzalo A.; Panotopoulos, Grigoris; Soto, Alex

    2016-01-01

    If cosmic inflation suffered tiny time-dependent deviations from the slow-roll regime, these would induce the existence of small scale-dependent features imprinted in the primordial spectra, with their shapes and sizes revealing information about the physics that produced them. Small sharp features could be suppressed at the level of the two-point correlation function, making them undetectable in the power spectrum, but could be amplified at the level of the three-point correlation function, offering us a window of opportunity to uncover them in the non-Gaussian bispectrum. In this article, we show that sharp features may be analyzed using only data coming from the three point correlation function parametrizing primordial non-Gaussianity. More precisely, we show that if features appear in a particular non-Gaussian triangle configuration (e.g. equilateral, folded, squeezed), these must reappear in every other configuration according to a specific relation allowing us to correlate features across the non-Gaussian bispectrum. As a result, we offer a method to study scale-dependent features generated during inflation that depends only on data coming from measurements of non-Gaussianity, allowing us to omit data from the power spectrum.

  9. Spacecraft Health Automated Reasoning Prototype (SHARP): The fiscal year 1989 SHARP portability evaluations task for NASA Solar System Exploration Division's Voyager project

    Atkinson, David J.; Doyle, Richard J.; James, Mark L.; Kaufman, Tim; Martin, R. Gaius

    1990-01-01

    A Spacecraft Health Automated Reasoning Prototype (SHARP) portability study is presented. Some specific progress is described on the portability studies, plans for technology transfer, and potential applications of SHARP and related artificial intelligence technology to telescience operations. The application of SHARP to Voyager telecommunications was a proof-of-capability demonstration of artificial intelligence as applied to the problem of real time monitoring functions in planetary mission operations. An overview of the design and functional description of the SHARP system is also presented as it was applied to Voyager.

  10. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, HVLP COATING EQUIPMENT, SHARPE MANUFACTURING COMPANY PLATINUM 2012 HVLP SPRAY GUN

    This report presents the results of the verification test of the Sharpe Platinum 2013 high-volume, low-pressure gravity-feed spray gun, hereafter referred to as the Sharpe Platinum, which is designed for use in automotive refinishing. The test coating chosen by Sharpe Manufacturi...

  11. Occupational exposure to sharps injury among healthcare providers in Ethiopia regional hospitals

    Sharew, Nigussie Tadesse; Mulu, Getaneh Baye; Habtewold, Tesfa Dejenie; Gizachew, Kefyalew Dagne

    2017-01-01

    BACKGROUND: Sharps injury is a penetrating stab wound from a needle, scalpel, or another sharp object that may result in exposure to blood or other body fluids. According to World Health Organization pooled estimate, the annual incidence of sharps injury in Africa was ranged from 2.10 to 4.68 per

  12. Depression following myocardial infarction

    Larsen, Karen Kjær

    2013-01-01

    whether the mental burden of MI is so heavy that it increases the risk of suicide. Although post-MI depression is common and burdensome, the condition remains under-recognised and under-treated. The development of new strategies to improve the quality of care for people with post-MI depression requires...... between post-MI depression and new cardiovascular events or death, taking potential mediators into account (Paper III); 4. To examine the association between MI and suicide (Paper IV). Two different study designs were employed: a population-based cohort study using data obtained from registers......Myocardial infarction (MI) is a severe life event that is accompanied by an increased risk of depression. Mounting evidence suggests that post-MI depression is associated with adverse outcomes, but the underlying mechanisms of this association remain unclear, and no previous studies have examined...

  13. A very sharp drop in the photovoltaic market

    Boulanger, V.

    2013-01-01

    For the second year in a row the photovoltaic market is in sharp decline in France, it dropped by 37% between 2011 and 2012 and the situation for 2013 is expected to be even worse. The last emergency measures taken by the government have been useless. The syndicate of renewable energies (SER) and the 'Europe Ecologie les Verts' party urge the government to take efficient emergency measures like for instance the implementation of local purchase tariffs instead of the present bidding process or to keep the obligation of the integration to the building only for new constructions. The only good piece of news is that photovoltaic power is getting more and more competitive. France has to reconsider its energy policy and its regulatory framework in order to benefit from it. (A.C.)

  14. SHARP - Automated monitoring of spacecraft health and status

    Atkinson, David J.; James, Mark L.; Martin, R. G.

    1990-01-01

    Briefly discussed here are the spacecraft and ground systems monitoring process at the Jet Propulsion Laboratory (JPL). Some of the difficulties associated with the existing technology used in mission operations are highlighted. A new automated system based on artificial intelligence technology is described which seeks to overcome many of these limitations. The system, called the Spacecraft Health Automated Reasoning Prototype (SHARP), is designed to automate health and status analysis for multi-mission spacecraft and ground data systems operations. The system has proved to be effective for detecting and analyzing potential spacecraft and ground systems problems by performing real-time analysis of spacecraft and ground data systems engineering telemetry. Telecommunications link analysis of the Voyager 2 spacecraft was the initial focus for evaluation of the system in real-time operations during the Voyager spacecraft encounter with Neptune in August 1989.

  15. SHARP: Automated monitoring of spacecraft health and status

    Atkinson, David J.; James, Mark L.; Martin, R. Gaius

    1991-01-01

    Briefly discussed here are the spacecraft and ground systems monitoring process at the Jet Propulsion Laboratory (JPL). Some of the difficulties associated with the existing technology used in mission operations are highlighted. A new automated system based on artificial intelligence technology is described which seeks to overcome many of these limitations. The system, called the Spacecraft Health Automated Reasoning Prototype (SHARP), is designed to automate health and status analysis for multi-mission spacecraft and ground data systems operations. The system has proved to be effective for detecting and analyzing potential spacecraft and ground systems problems by performing real-time analysis of spacecraft and ground data systems engineering telemetry. Telecommunications link analysis of the Voyager 2 spacecraft was the initial focus for evaluation of the system in real-time operations during the Voyager spacecraft encounter with Neptune in August 1989.

  16. Triomicrus Sharp of Eastern China (Coleoptera: Staphylinidae: Pselaphinae).

    Shen, Jia-Wei; Yin, Zi-Wei; Li, Li-Zhen

    2015-08-31

    Twelve species of the genus Triomicrus Sharp are here recognized in eastern China, with eleven of them described as new: T. Inaequalis Shen & Yin, sp. n. and T. mirus Shen & Yin, sp. n. from Anhui, T. abhorridus Shen & Yin, sp. n., T. aculeus Shen & Yin, sp. n., T. damingensis Shen & Yin, sp. n., T. frondosus Shen & Yin, sp. n., T. gutianensis Shen & Yin, sp. n. and T. tibialis Shen & Yin, sp. n. from Zhejiang, T. anfractus Shen & Yin, sp. n. from Anhui and Zhejiang, T. Hamus Shen & Yin, sp. n. from Jiangxi, and T. contus Shen & Yin, sp. n. from Jiangxi and Zhejiang. New distributional data for T. rougemonti Löbl, Kurbatov &Nomura is given. A key for the identification of the Triomicrus species in eastern China is presented.

  17. Real time algorithms for sharp wave ripple detection.

    Sethi, Ankit; Kemere, Caleb

    2014-01-01

    Neural activity during sharp wave ripples (SWR), short bursts of co-ordinated oscillatory activity in the CA1 region of the rodent hippocampus, is implicated in a variety of memory functions from consolidation to recall. Detection of these events in an algorithmic framework, has thus far relied on simple thresholding techniques with heuristically derived parameters. This study is an investigation into testing and improving the current methods for detection of SWR events in neural recordings. We propose and profile methods to reduce latency in ripple detection. Proposed algorithms are tested on simulated ripple data. The findings show that simple realtime algorithms can improve upon existing power thresholding methods and can detect ripple activity with latencies in the range of 10-20 ms.

  18. Sharp Interface Tracking in Rotating Microflows of Solvent Extraction

    Glimm, James; Almeida, Valmor de; Jiao, Xiangmin; Sims, Brett

    2013-01-01

    The objective of this project is to develop a specialized sharp interface tracking simulation capability for predicting interaction of micron-sized drops and bubbles in rotating flows relevant to optimized design of contactor devices used in solvent extraction processes of spent nuclear fuel reprocessing. The primary outcomes of this project include the capability to resolve drops and bubbles micro-hydrodynamics in solvent extraction contactors, determining from first principles continuum fluid mechanics how micro-drops and bubbles interact with each other and the surrounding shearing fluid for realistic flows. In the near term, this effort will play a central role in providing parameters and insight into the flow dynamics of models that average over coarser scales, say at the millimeter unit length. In the longer term, it will prove to be the platform to conduct full-device, detailed simulations as parallel computing power reaches the exaflop level. The team will develop an accurate simulation tool for flows containing interacting droplets and bubbles with sharp interfaces under conditions that mimic those found in realistic contactor operations. The main objective is to create an off-line simulation capability to model drop and bubble interactions in a domain representative of the averaged length scale. The technical approach is to combine robust interface tracking software, subgrid modeling, validation quality experiments, powerful computational hardware, and a team with simulation modeling, physical modeling and technology integration experience. Simulations will then fully resolve the microflow of drops and bubbles at the microsecond time scale. This approach is computationally intensive but very accurate in treating important coupled physical phenomena in the vicinity of interfaces. The method makes it possible to resolve spatial scales smaller than the typical distance between bubbles and to model some non-equilibrium thermodynamic features such as finite

  19. The effective field theory of inflation models with sharp features

    Bartolo, Nicola; Cannone, Dario; Matarrese, Sabino

    2013-01-01

    We describe models of single-field inflation with small and sharp step features in the potential (and sound speed) of the inflaton field, in the context of the Effective Field Theory of Inflation. This approach allows us to study the effects of features in the power-spectrum and in the bispectrum of curvature perturbations, from a model-independent point of view, by parametrizing the features directly with modified ''slow-roll'' parameters. We can obtain a self-consistent power-spectrum, together with enhanced non-Gaussianity, which grows with a quantity β that parametrizes the sharpness of the step. With this treatment it is straightforward to generalize and include features in other coefficients of the effective action of the inflaton field fluctuations. Our conclusion in this case is that, excluding extrinsic curvature terms, the only interesting effects at the level of the bispectrum could arise from features in the first slow-roll parameter ε or in the speed of sound c s . Finally, we derive an upper bound on the parameter β from the consistency of the perturbative expansion of the action for inflaton perturbations. This constraint can be used for an estimation of the signal-to-noise ratio, to show that the observable which is most sensitive to features is the power-spectrum. This conclusion would change if we consider the contemporary presence of a feature and a speed of sound c s < 1, as, in such a case, contributions from an oscillating folded configuration can potentially make the bispectrum the leading observable for feature models

  20. Sharp Interface Tracking in Rotating Microflows of Solvent Extraction

    Glimm, James [Stony Brook Univ., NY (United States); Almeida, Valmor de [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jiao, Xiangmin [Stony Brook Univ., NY (United States); Sims, Brett [City Univ. (CUNY), NY (United States). Borough of Manhattan Community College; Li, Xaiolin [Stony Brook Univ., NY (United States)

    2013-01-08

    The objective of this project is to develop a specialized sharp interface tracking simulation capability for predicting interaction of micron-sized drops and bubbles in rotating flows relevant to optimized design of contactor devices used in solvent extraction processes of spent nuclear fuel reprocessing. The primary outcomes of this project include the capability to resolve drops and bubbles micro-hydrodynamics in solvent extraction contactors, determining from first principles continuum fluid mechanics how micro-drops and bubbles interact with each other and the surrounding shearing fluid for realistic flows. In the near term, this effort will play a central role in providing parameters and insight into the flow dynamics of models that average over coarser scales, say at the millimeter unit length. In the longer term, it will prove to be the platform to conduct full-device, detailed simulations as parallel computing power reaches the exaflop level. The team will develop an accurate simulation tool for flows containing interacting droplets and bubbles with sharp interfaces under conditions that mimic those found in realistic contactor operations. The main objective is to create an off-line simulation capability to model drop and bubble interactions in a domain representative of the averaged length scale. The technical approach is to combine robust interface tracking software, subgrid modeling, validation quality experiments, powerful computational hardware, and a team with simulation modeling, physical modeling and technology integration experience. Simulations will then fully resolve the microflow of drops and bubbles at the microsecond time scale. This approach is computationally intensive but very accurate in treating important coupled physical phenomena in the vicinity of interfaces. The method makes it possible to resolve spatial scales smaller than the typical distance between bubbles and to model some non-equilibrium thermodynamic features such as finite

  1. Age Is Associated with Reduced Sharp-Wave Ripple Frequency and Altered Patterns of Neuronal Variability.

    Wiegand, Jean-Paul L; Gray, Daniel T; Schimanski, Lesley A; Lipa, Peter; Barnes, C A; Cowen, Stephen L

    2016-05-18

    Spatial and episodic memory performance declines with age, and the neural basis for this decline is not well understood. Sharp-wave ripples are brief (∼70 ms) high-frequency oscillatory events generated in the hippocampus and are associated with the consolidation of spatial memories. Given the connection between ripple oscillations and memory consolidation, we investigated whether the structure of ripple oscillations and ripple-triggered patterns of single-unit activity are altered in aged rats. Local field and single-unit activity surrounding sharp-wave ripple events were examined in the CA1 region of the hippocampus of old (n = 5) and young (n = 6) F344 rats during periods of rest preceding and following performance on a place-dependent eyeblink-conditioning task. Neural responses in aged rats differed from responses in young rats in several ways. First, compared with young rats, the rate of ripple occurrence (ripple density) is reduced in aged rats during postbehavior rest. Second, mean ripple frequency during prebehavior and postbehavior rest is lower in aged animals (aged: 132 Hz; young: 146 Hz). Third, single neurons in aged animals responded more consistently from ripple to ripple. Fourth, variability in interspike intervals was greater in aged rats. Finally, neurons were tuned to a narrower range of phases of the ripple oscillation relative to young animals. Together, these results suggest that the CA1 network in aged animals has a reduced "vocabulary" of available representational states. The hippocampus is a structure that is critical for the formation of episodic memories. Sharp-wave ripple events generated in the hippocampus have been implicated in memory consolidation processes critical to memory stabilization. We examine here whether these ripple oscillations are altered over the course of the life span, which could contribute to hippocampus-dependent memory deficits that occur during aging. This experiment used young and aged memory-impaired rats

  2. Phase-field model of eutectic growth

    Karma, A.

    1994-01-01

    A phase-field model which describes the solidification of a binary eutectic alloy with a simple symmetric phase diagram is introduced and the sharp-interface limit of this model is explored both analytically and numerically

  3. Scan analysis in myocardial infarction

    Ell, P J [Landesunfallkrankenhaus, Feldkirch (Austria). Inst. fuer Strahlenmedizin

    1976-08-01

    Myocardial scans with sup(99m)Tc-labelled phosphates are reported to be useful in the diagnosis of acute myocardial infarction. A retrospective survey of 205 patients referred for sup(99m)Tc-phophate bone scanning and with no evidence of recent heart disease revealed an occurrence of 10% of false positive images, that is to say, uptake of phosphate in non-infarcted mayocardium. These striking findings stress the need for critical assessment of the usefulness of this diagnostic technique.

  4. Myocardial scintigraphy: methods and indications

    Knapp, W.H.

    1993-01-01

    Myocardial scintigraphy comprises perfusion imaging using TI-201 or - more recently - Tc-99m-labeled compounds with high affinity to myocytes. Imaging with these agents has become an important procedure in the detection of coronary artery disease, particularly in patients with non-diagnostic stress-ECG, in the functional evaluation of coronary stenoses after angiographical documentation in order to meet the adequate therapy decision, in therapy monitoring and follow-up, in the post infarction assessment of myocardial viability and differentiation between severe ischemia and scar and, occasionally, in acute ischemia. The use of positron emitters does not offer significant advantages for mere perfusion imaging, but is indispensable for the scintigraphic investigation of certain aspects of myocardial metabolism, particularly for the differentiation of viable ischemic wall segments from irreversibly damaged tissue. Imaging of myocardial necrosis has been improved by the introduction of labeled antimyosin antibody fragments and offers a considerable clinical potential in the diagnosis of myocarditis and cardiac transplant rejection. Neurohumoral aspects are increasingly involved in our understanding of myocardial failure. Scintigraphy of innervation/neurotransmission contributes to the investigation of pathophysiological alterations in myocardial insufficiency and in heart transplants. (orig.) [de

  5. Treatment of sharp mandibular alveolar process with hybrid prosthesis

    Sukaedi Sukaedi

    2010-09-01

    Full Text Available Background: Losing posterior teeth for a long time would occasionally lead to the sharpening of alveolar process. The removable partial denture usually have problems when used during mastication, because of the pressure on the mucosa under the alveolar ridge. Purpose: The purpose of this case report was to manage patients with sharp mandibular alveolar process by wearing hybrid prosthesis with extra coronal precision attachment retention and soft liner on the surface base beneath the removable partial denture. Case: A 76 years old woman visited the Prosthodontic Clinic Faculty of Dentistry Airlangga University. The patient had a long span bridge on the upper jaw and a free end acrylic removable partial denture on the lower jaw. She was having problems with mastication. The patient did not wear her lower denture because of the discomfort with it during mastication. Hence, she would like to replace it with a new removable partial denture. Case management: The patient was treated by wearing a hybrid prosthesis with extra coronal precision attachment on the lower jaw. Soft liner was applied on the surface of the removable partial denture. Hybrid prosthesis is a complex denture consisting of removable partial denture and fixed bridge. Conclusion: It concluded that after restoration, the patient had no problems with sharp alveolar process with her new denture, and she was able to masticate well.Latar belakang: Kehilangan geligi posterior dapat menimbulkan processus alveolaris tajam. Gigi tiruan sebagian lepasan mempunyai masalah selama pengunyahan karena adanya tekanan di mukosa di bawah alveolar ridge. Tujuan: Tujuan laporan kasus ini adalah untuk menjelaskan cara menangani pasien yang mempunyai prosesus alveolaris yang tajam di rahang bawah dengan dibuatkan protesis hybrid dengan daya tahan extra coronal precision attachment dan soft liner di permukaan bawah basis gigi tiruan sebagian lepasan. Kasus: Pasien wanita berumur 76 tahun datang di klinik

  6. Localness of energy cascade in hydrodynamic turbulence, II. Sharp spectral filter

    Aluie, Hussein [Los Alamos National Laboratory; Eyink, Gregory L [JOHNS HOPKINS UNIV.

    2009-01-01

    We investigate the scale-locality of subgrid-scale (SGS) energy flux and interband energy transfers defined by the sharp spectral filter. We show by rigorous bounds, physical arguments, and numerical simulations that the spectral SGS flux is dominated by local triadic interactions in an extended turbulent inertial range. Interband energy transfers are also shown to be dominated by local triads if the spectral bands have constant width on a logarithmic scale. We disprove in particular an alternative picture of 'local transfer by nonlocal triads,' with the advecting wavenumber mode at the energy peak. Although such triads have the largest transfer rates of all individual wavenumber triads, we show rigorously that, due to their restricted number, they make an asymptotically negligible contribution to energy flux and log-banded energy transfers at high wavenumbers in the inertial range. We show that it is only the aggregate effect of a geometrically increasing number of local wavenumber triads which can sustain an energy cascade to small scales. Furthermore, nonlocal triads are argued to contribute even less to the space-average energy flux than is implied by our rigorous bounds, because of additional cancellations from scale-decorrelation effects. We can thus recover the -4/3 scaling of nonlocal contributions to spectral energy flux predicted by Kraichnan's abridged Lagrangian-history direct-interaction approximation and test-field model closures. We support our results with numerical data from a 512{sup 3} pseudospectral simulation of isotropic turbulence with phase-shift dealiasing. We also discuss a rigorous counterexample of Eyink [Physica D 78, 222 (1994)], which showed that nonlocal wavenumber triads may dominate in the sharp spectral flux (but not in the SGS energy flux for graded filters). We show that this mathematical counter example fails to satisfy reasonable physical requirements for a turbulent velocity field, which are employed in our

  7. Short-time quantum dynamics of sharp boundaries potentials

    Granot, Er' el, E-mail: erel@ariel.ac.il; Marchewka, Avi

    2015-02-15

    Despite the high prevalence of singular potential in general, and rectangular potentials in particular, in applied scattering models, to date little is known about their short time effects. The reason is that singular potentials cause a mixture of complicated local as well as non-local effects. The object of this work is to derive a generic method to calculate analytically the short-time impact of any singular potential. In this paper it is shown that the scattering of a smooth wavefunction on a singular potential is totally equivalent, in the short-time regime, to the free propagation of a singular wavefunction. However, the latter problem was totally addressed analytically in Ref. [7]. Therefore, this equivalency can be utilized in solving analytically the short time dynamics of any smooth wavefunction at the presence of a singular potentials. In particular, with this method the short-time dynamics of any problem where a sharp boundaries potential (e.g., a rectangular barrier) is turned on instantaneously can easily be solved analytically.

  8. Short-time quantum dynamics of sharp boundaries potentials

    Granot, Er'el; Marchewka, Avi

    2015-02-01

    Despite the high prevalence of singular potential in general, and rectangular potentials in particular, in applied scattering models, to date little is known about their short time effects. The reason is that singular potentials cause a mixture of complicated local as well as non-local effects. The object of this work is to derive a generic method to calculate analytically the short-time impact of any singular potential. In this paper it is shown that the scattering of a smooth wavefunction on a singular potential is totally equivalent, in the short-time regime, to the free propagation of a singular wavefunction. However, the latter problem was totally addressed analytically in Ref. [7]. Therefore, this equivalency can be utilized in solving analytically the short time dynamics of any smooth wavefunction at the presence of a singular potentials. In particular, with this method the short-time dynamics of any problem where a sharp boundaries potential (e.g., a rectangular barrier) is turned on instantaneously can easily be solved analytically.

  9. Short-time quantum dynamics of sharp boundaries potentials

    Granot, Er'el; Marchewka, Avi

    2015-01-01

    Despite the high prevalence of singular potential in general, and rectangular potentials in particular, in applied scattering models, to date little is known about their short time effects. The reason is that singular potentials cause a mixture of complicated local as well as non-local effects. The object of this work is to derive a generic method to calculate analytically the short-time impact of any singular potential. In this paper it is shown that the scattering of a smooth wavefunction on a singular potential is totally equivalent, in the short-time regime, to the free propagation of a singular wavefunction. However, the latter problem was totally addressed analytically in Ref. [7]. Therefore, this equivalency can be utilized in solving analytically the short time dynamics of any smooth wavefunction at the presence of a singular potentials. In particular, with this method the short-time dynamics of any problem where a sharp boundaries potential (e.g., a rectangular barrier) is turned on instantaneously can easily be solved analytically

  10. An evaluation of sharp safety blood evacuation devices.

    Ford, Joanna; Phillips, Peter

    This article describes an evaluation of three sharp safety blood evacuation devices in seven Welsh NHS boards and the Welsh Blood Service. Products consisted of two phlebotomy needles possessing safety shields and one phlebotomy device with wings, tubing and a retractable needle. The device companies provided the devices and appropriate training. Participating healthcare workers used the safety device instead of the conventional device to sample blood during the evaluation period and each type of device was evaluated in random order. Participants filled in a questionnaire for each type of device and then a further questionnaire comparing the two shielded evacuation needles with each other Results showed that responses to all three products were fairly positive, although each device was not liked by everyone who used it. When the two shielded evacuation devices were compared with each other, most users preferred the device with the shield positioned directly above the needle to the device with the shield at the side. However, in laboratory tests, the preferred device produced more fluid splatter than the other shielded device on activation.

  11. Acute Myocardial Infarction Patients

    Bruce Ovbiagele

    2011-01-01

    Full Text Available Background. Diabetes mellitus (DM confers high vascular risk and is a growing national epidemic. We assessed clinical characteristics and prevalence of diagnosed DM among patients hospitalized with acute myocardial infarction (AMI in the US over the last decade. Methods. Data were obtained from all states within the US that contributed to the Nationwide Inpatient Sample. All patients admitted to hospitals between 1997 and 2006 with a primary discharge diagnosis of AMI were included. Time trends in the proportion of these patients with DM diagnosis were computed. Results. The portion of patients with comorbid diabetes among AMI hospitalizations increased substantially from 18% in 1997 to 30% in 2006 (<.0001. Absolute numbers of AMI hospitalizations in the US decreased 8% (from 729, 412 to 672, 243, while absolute numbers of AMI hospitalizations with coexisting DM rose 51% ((131, 189 to 198, 044, both (<.0001. Women with AMI were significantly more likely to have DM than similarly aged men, but these differences diminished with increasing age. Conclusion. Although overall hospitalizations for AMI in the US diminished over the last decade, prevalence of diabetes rose substantially. This may have important consequences for the future societal vascular disease burden.

  12. Myocardial perfusion imaging for detection of silent myocardial ischemia

    Beller, G.A.

    1988-01-01

    Despite the widespread use of the exercise stress test in diagnosing asymptomatic myocardial ischemia, exercise radionuclide imaging remains useful for detecting silent ischemia in numerous patient populations, including those who are totally asymptomatic, those who have chronic stable angina, those who have recovered from an episode of unstable angina or an uncomplicated myocardial infarction, and those who have undergone angioplasty or received thrombolytic therapy. Studies show that thallium scintigraphy is more sensitive than exercise electrocardiography in detecting ischemia, i.e., in part, because perfusion defects occur more frequently than ST depression and before angina in the ischemic cascade. Thallium-201 scintigraphy can be performed to differentiate a true- from a false-positive exercise electrocardiographic test in patients with exercise-induced ST depression and no angina. The development of technetium-labeled isonitriles may improve the accuracy of myocardial perfusion imaging. 11 references

  13. Time-clustering behavior of sharp fluctuation sequences in Chinese stock markets

    Yuan Ying; Zhuang Xintian; Liu Zhiying; Huang Weiqiang

    2012-01-01

    Sharp fluctuations (in particular, extreme fluctuations) of asset prices have a great impact on financial markets and risk management. Therefore, investigating the time dynamics of sharp fluctuation is a challenge in the financial fields. Using two different representations of the sharp fluctuations (inter-event times and series of counts), the time clustering behavior in the sharp fluctuation sequences of stock markets in China is studied with several statistical tools, including coefficient of variation, Allan Factor, Fano Factor as well as R/S (rescaled range) analysis. All of the empirical results indicate that the time dynamics of the sharp fluctuation sequences can be considered as a fractal process with a high degree of time-clusterization of the events. It can help us to get a better understanding of the nature and dynamics of sharp fluctuation of stock price in stock markets.

  14. Influence of gantry angle in helical computed tomography. Usefullness of 1-dimension sharpness filter

    Kawano, Hirofumi; Suzuki, Toru; Matsuura, Shigeru; Kai, Tsuyoshi; Shimizu, Toshiyuki [Hyuga Hospital of Saiseikai Foundation, Kadogawa, Miyazaki (Japan)

    2001-05-01

    When we let gantry tilt and do scan in helical CT, vertical sharpness deteriorates. We were able to revise it with 1-dimensional sharpness filter which the square sum of difference of MTF was compared, and was designed this time. And the unsharpness was in proportion to sin of gantry angle. As a result, we led several sets of frequency emphasis degree. There is a model to built 1-dimension sharpness filter in a scan plan. It is useful for clinical diagnoses. (author)

  15. Influence of gantry angle in helical computed tomography. Usefullness of 1-dimension sharpness filter

    Kawano, Hirofumi; Suzuki, Toru; Matsuura, Shigeru; Kai, Tsuyoshi; Shimizu, Toshiyuki

    2001-01-01

    When we let gantry tilt and do scan in helical CT, vertical sharpness deteriorates. We were able to revise it with 1-dimensional sharpness filter which the square sum of difference of MTF was compared, and was designed this time. And the unsharpness was in proportion to sin of gantry angle. As a result, we led several sets of frequency emphasis degree. There is a model to built 1-dimension sharpness filter in a scan plan. It is useful for clinical diagnoses. (author)

  16. Radioimmunoassay determination of factor 4 platelets (PF4) in acute myocardial infarction patients

    Leon Herrejon, Ma. de L.; Graef S, A.; Altamirano B, P.; Ramos C, M.A.

    1985-01-01

    From a pathological standpoint an increase in the Factor 4 platelet has been observed in various abnormal states including myocardial infarction, diabetes mellitus, diffuse intravascular coagulation and renal insufficiency among others. Eighty subjects were studied at rest: 40 normal and under no medication, and 40 myocardial infarction patients in the acute phase and with added pathology. All were under the same therapeutic regimen. Results obtained between both groups were statistically significant with a P > 0.01. (author)

  17. GATED SPECT TO EVALUATE LEFT VENTRICULAR MYOCARDIAL PERFUSION, FUNCTION AND DYSSYNCHRONY FOR RESYNCHRONIZATION THERAPY

    E.N. Ostroumov

    2009-01-01

    Full Text Available The study included 15 consecutive patients with heart failure and substantial LV dyssynchrony undergoing CRT. Clinical and phase analysis of gated myocardial perfusion SPECT assessed at baseline, after 2–3 days and after 3–4 months of CRT. The results demonstrated inversely relationship between the response to CRT and the nonviable myocardium. Evaluation of myocardial viability is necessary to considered in the selection process for CRT.

  18. [Myocardial perfusion imaging by digital subtraction angiography].

    Kadowaki, H; Ishikawa, K; Ogai, T; Katori, R

    1986-03-01

    Several methods of digital subtraction angiography (DSA) were compared to determine which could better visualize regional myocardial perfusion using coronary angiography in seven patients with myocardial infarction, two with angina pectoris and five with normal coronary arteries. Satisfactory DSA was judged to be achieved if the shape of the heart on the mask film was identical to that on the live film and if both films were exactly superimposed. To obtain an identical mask film in the shape of each live film, both films were selected from the following three phases of the cardiac cycle; at the R wave of the electrocardiogram, 100 msec before the R wave, and 200 msec before the R wave. The last two were superior for obtaining mask and live films which were similar in shape, because the cardiac motion in these phases was relatively small. Using these mask and live films, DSA was performed either with the continuous image mode (CI mode) or the time interval difference mode (TID mode). The overall perfusion of contrast medium through the artery to the vein was adequately visualized using the CI mode. Passage of contrast medium through the artery, capillary and vein was visualized at each phase using TID mode. Subtracted images were displayed and photographed, and the density of the contrast medium was adequate to display contour lines as in a relief map. Using this DSA, it was found that regional perfusion of the contrast medium was not always uniform in normal subjects, depending on the typography of the coronary artery.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Mortality rate in type 2 myocardial infarction

    Saaby, Lotte; Poulsen, Tina Svenstrup; Diederichsen, Axel Cosmus Pyndt

    2014-01-01

    myocardial infarction, hypercholesterolemia, high p-creatinine, and diabetes mellitus. The multivariable-adjusted hazard ratio for type 2 myocardial infarction was 2.0 (95% confidence interval, 1.3-3.0). With shock as the only exception, mortality was independent of the triggering conditions leading to type....../119) in those with type 2 myocardial infarction and 26% (92/360) in those with type 1 myocardial infarction (P high age, prior myocardial infarction, type 2...... 2 myocardial infarction. CONCLUSIONS: Mortality in patients with type 2 myocardial infarction is high, reaching approximately 50% after 2 years. Further descriptive and survival studies are needed to improve the scientific evidence on which treatment of type 2 myocardial infarction is based....

  20. Sgarbossa criteria and acute myocardial infarction.

    Alang, Neha; Bathina, Jaya; Kranis, Mark; Angelis, Dimitrios

    2010-01-01

    Diagnosis of acute ST-elevation myocardial infarction in the presence of left bundle branch block is difficult. present a case of acute myocardial infarction with LBBB diagnosed and treated using the Sgarbossa criteria.

  1. The endothelial glycocalyx protects against myocardial edema

    van den Berg, Bernard M.; Vink, Hans; Spaan, Jos A. E.

    2003-01-01

    Myocardial tissue edema attributable to increased microvascular fluid loss contributes to cardiac dysfunction after myocardial ischemia, cardiopulmonary bypass, hypertension, and sepsis. Recent studies suggest that carbohydrate structures on the luminal surface of microvascular endothelium are

  2. ASSESSMENT OF THE MANAGEMENT OF SHARPS INJURIES IN GOVERNMENT HOSPITALS: THE MALAYSIAN SITUATION

    M. Siti Haniza M.D PhD

    2012-11-01

    Full Text Available Introduction: Management of occupational hazards has been a priority and sharps injuries is a known potential risk to health care workers. With the known risks of potential infections, to the workers as well as the patients, our workers need protection from further danger. Objective: This study looked at the measures taken on managing the affected healthcare workers. Methods: A cross-sectional survey using self-administered questionnaire was sent to 55 hospital directors. They were required to inform on their management practices on sharps injuries. Results: The findings showed variations in the management of sharps injuries during and after office hours, variation in the site of keeping the records, person responsible and variation in the frequency of data analysis and presentation to hospital directors. Discussion: According to OSHA Act 1994, it is the responsibility of the employer to ensure safety, health and welfare of the employee. In management of sharps injury data from injury reporting should be compiled and assessed. Reporting feedback need to be encouraged with timely follow-up of all sharps injury cases. Reporting of sharps injuries is essential to ensure that all healthcare workers receive appropriate post-exposure medical treatment. Conclusion & Recommendation: A uniform management of sharps injuries protocol need to be established to improve reporting. An avenue to present sharps injuries data regularly is needed so as appropriate management of workers be ensured. Therefore adherence to the available guidelines need to be ensured. Key words: management, sharps injuries, healthcare workers

  3. Serotonin dependent masking of hippocampal sharp wave ripples.

    ul Haq, Rizwan; Anderson, Marlene L; Hollnagel, Jan-Oliver; Worschech, Franziska; Sherkheli, Muhammad Azahr; Behrens, Christoph J; Heinemann, Uwe

    2016-02-01

    Sharp wave ripples (SPW-Rs) are thought to play an important role in memory consolidation. By rapid replay of previously stored information during slow wave sleep and consummatory behavior, they result from the formation of neural ensembles during a learning period. Serotonin (5-HT), suggested to be able to modify SPW-Rs, can affect many neurons simultaneously by volume transmission and alter network functions in an orchestrated fashion. In acute slices from dorsal hippocampus, SPW-Rs can be induced by repeated high frequency stimulation that induces long-lasting LTP. We used this model to study SPW-R appearance and modulation by 5-HT. Although stimulation in presence of 5-HT permitted LTP induction, SPW-Rs were "masked"--but appeared after 5-HT wash-out. This SPW-R masking was dose dependent with 100 nM 5-HT being sufficient--if the 5-HT re-uptake inhibitor citalopram was present. Fenfluramine, a serotonin releaser, could also mask SPW-Rs. Masking was due to 5-HT1A and 5-HT2A/C receptor activation. Neither membrane potential nor membrane conductance changes in pyramidal cells caused SPW-R blockade since both remained unaffected by combining 5-HT and citalopram. Moreover, 10 and 30 μM 5-HT mediated SPW-R masking preceded neuronal hyperpolarization and involved reduced presynaptic transmitter release. 5-HT, as well as a 5-HT1A agonist, augmented paired pulse facilitation and affected the coefficient of variance. Spontaneous SPW-Rs in mice hippocampal slices were also masked by 5-HT and fenfluramine. While neuronal ensembles can acquire long lasting LTP during higher 5-HT levels, lower 5-HT levels enable neural ensembles to replay previously stored information and thereby permit memory consolidation memory. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Diagnosis of coronary artery disease by thallium-201 myocardial scintigraphy with intravenous infusion of SUNY4001 (adenosine) in effort angina pectoris. The clinical trial report at multi-center. Phase II

    Sakata, Yasushi; Kodama, Kazuhisa; Nishimura, Tsunehiko; Kajiya, Teishi; Kato, Kazuzo

    2004-01-01

    Forty-four patients with effort angina pectoris were evaluated with SUNY4001 (adenosine) thallium-201 ( 201 Tl) myocardial scintigraphy to detect coronary artery disease. These patients had single-vessel disease (≥American Heart Association (AHA) 90% stenosis) in either right coronary artery (RCA) or left anterior descending (LAD). Adenosine was infused at the rate of 120 or 140 μg/kg/min for six minutes. One hundred eleven MBq of 201 Tl was injected after three minutes of the start of the infusion. The early and delayed images were obtained by SPECT imaging. The sensitivity was 94.7% at 120 μg/kg/min and 84.2% at 140 μg/kg/min. Adenosine 201 Tl myocardial scintigraphy showed high accuracy for detecting significant coronary artery disease. Adverse reactions occurred in 77.3% of the patients. Regarding the rates of the adverse reactions, there was no significant difference between 120 and 140 μg/kg/min. Major adverse reactions were Chest pain/discomfort (52.3%) and Flushing/Feeling of warmth (27.3%). No serious complication was observed at any infusion rate. Most of adverse reactions disappeared shortly. Only two patients required treatment for moderate chest pain, which, however, disappeared in several minutes. One of the treatments was merely the termination of adenosine infusion, and the other was sublingual spray of nitroglycerin. Adenosine infusion caused slight decrease in blood pressure and increase in heart rate. The hemodynamic changes resolved within several minutes after the adenosine infusion. Decrease in systolic blood pressure of more than 20 mmHg from the base level occurred in 26.1% and 52.4% at 120 and 140 μg/kg/min infusion rate respectively. Therefore, the adenosine infusion at 120 μg/kg/min should be considered safe and useful for the diagnosis of coronary artery disease by pharmacologic stress imaging. (author)

  5. MANAGEMENT OF DIABETES IN ACUTE MYOCARDIAL INFARCTION IN CELJE GENERAL HOSPITAL IN 1999

    Gregor Veninšek

    2001-12-01

    Full Text Available Background. DIGAMI study showed that intrahospital mortality and mortality at one year after myocardial infarction can be significantly reduced in diabetics treated in acute phase of myocardial infarction by GI infusion and afterwards for at least three months with intensive insulin treatment. Mortality can be reduced for more than 50% in a subgroup of patients younger than 70 years, without congestive heart failure, with first myocardial infarction, not treated with insulin or digitalis. In this perspective we reviewed treatment of diabetics with acute myocardial infarction in 1999 in Celje General Hospital.Methods. We reviewed documentation of treatment of all diabetics with acute myocardial infarction treated in Celje General Hospital in 1999. We collected data on number of newly discovered diabetes, on previous treatment of diabetes, on treatment of diabetes during hospitalization and at discharge, on drugs used for treatment of diabetes and on mortality during hospitalization.Results. Diabetics presented 20% of all patients with acute myocardial infarction treated in Celje General Hospital in 1999. None of patients received GI infusion, none had intensively managed blood sugar. 24% of patients were treated with sulfonylureas in acute phase of myocardial infarction. 33% of patients were discharged from hospital with insulin therapy. Intrahospital mortality was 9%, comparable with patients without diabetes.Conclusions. In 1999 was intrahospital treatment of diabetics with acute myocardial infarction in Celje General Hospital successful as their intrahospital mortality equaled non-diabetics. Treatment of diabetes itself, during hospitalization and after discharge, on the other hand, in 1999 had not been up to date according to results of recent studies. In our opinion, it is mandatory for diabetologist to make part of the team that treats diabetic with acute myocardial infarction

  6. Myocardial infarction after near drowning.

    Chen, Li-Bang; Lai, Yen-Chun; Chen, Chang-Chih; Chang, Wen-Han; Su, Yu-Jang

    2008-06-01

    During summer, near drowning is a common accident in Taiwan. It may lead to multiple organ damages in cases where severe hypothermia and hypoxemia occur. We present a case of myocardial infarction after near drowning. The patient was sent to our ED by the emergency medical services called by the witness. On arrival to our ED, hypothermia and hypoxemia overcame him. Endotracheal intubation and warm intravenous fluid were applied at once owing to drowsy consciousness, respiratory distress, and hypothermia. Electrocardiogram showed diffuse ST-segment elevation over the precordial leads V2-V6. The initial level of cardiac enzymes was within normal limit but elevated in troponin I on the second day after hospitalization. We presumed that the possibility of myocardial infarction resulted from near drowning-related hypoxemia. To our knowledge, this is the first case describing myocardial injury with electrocardiogram changes after near drowning.

  7. Dynamic CT myocardial perfusion imaging

    Caruso, Damiano; Eid, Marwen; Schoepf, U. Joseph; Jin, Kwang Nam; Varga-Szemes, Akos; Tesche, Christian; Mangold, Stefanie

    2016-01-01

    Highlights: • CT myocardial perfusion provides functional assessment of the myocardium. • CCTA is limited in determining the hemodynamic significance of coronary stenosis. • CT-MPI can accurately detect hemodynamically significant coronary artery stenosis. - Abstract: Non-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT based technologies. Coronary CT angiography has been shown to reliably assess coronary anatomy and detect high risk coronary artery disease. However, this technique is limited to anatomical assessment, thus non-invasive techniques for functional assessment of the heart are necessary. CT myocardial perfusion is a new CT based technique that provides functional assessment of the myocardium and allows for a comprehensive assessment of coronary artery disease with a single modality when combined with CTA. This review aims to discuss dynamic CT myocardial perfusion as a new technique in the assessment of CAD.

  8. Dynamic CT myocardial perfusion imaging

    Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncological and Pathological Sciences, University of Rome “Sapienza”, Latina (Italy); Eid, Marwen [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States); Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul (Korea, Republic of); Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Mangold, Stefanie [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Tuebingen (Germany); and others

    2016-10-15

    Highlights: • CT myocardial perfusion provides functional assessment of the myocardium. • CCTA is limited in determining the hemodynamic significance of coronary stenosis. • CT-MPI can accurately detect hemodynamically significant coronary artery stenosis. - Abstract: Non-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT based technologies. Coronary CT angiography has been shown to reliably assess coronary anatomy and detect high risk coronary artery disease. However, this technique is limited to anatomical assessment, thus non-invasive techniques for functional assessment of the heart are necessary. CT myocardial perfusion is a new CT based technique that provides functional assessment of the myocardium and allows for a comprehensive assessment of coronary artery disease with a single modality when combined with CTA. This review aims to discuss dynamic CT myocardial perfusion as a new technique in the assessment of CAD.

  9. Morphological aspects of myocardial bridges.

    Lujinović, Almira; Kulenović, Amela; Kapur, Eldan; Gojak, Refet

    2013-11-01

    Although some myocardial bridges can be asymptomatic, their presence often causes coronary disease either through direct compression of the "tunnel" segment or through stimulation and accelerated development of atherosclerosis in the segment proximally to the myocardial bridge. The studied material contained 30 human hearts received from the Department of Anatomy. The hearts were preserved 3 to 5 days in 10% formalin solution. Thereafter, the fatty tissue was removed and arterial blood vessels prepared by careful dissection with special reference to the presence of the myocardial bridges. Length and thickness of the bridges were measured by the precise electronic caliper. The angle between the myocardial bridge fibre axis and other axis of the crossed blood vessel was measured by a goniometer. The presence of the bridges was confirmed in 53.33% of the researched material, most frequently (43.33%) above the anterior interventricular branch. The mean length of the bridges was 14.64 ± 9.03 mm and the mean thickness was 1.23 ± 1.32 mm. Myocardial bridge fibres pass over the descending blood vessel at the angle of 10-90 degrees. The results obtained on a limited sample suggest that the muscular index of myocardial bridge is the highest for bridges located on RIA, but that the difference is not significant in relation to bridges located on other branches. The results obtained suggest that bridges located on other branches, not only those on RIA, could have a great contractive power and, consequently, a great compressive force, which would be exerted on the wall of a crossed blood vessel.

  10. Different Causes of Death in Patients with Myocardial Infarction Type 1, Type 2, and Myocardial Injury.

    Lambrecht, Sascha; Sarkisian, Laura; Saaby, Lotte; Poulsen, Tina S; Gerke, Oke; Hosbond, Susanne; Diederichsen, Axel C P; Thygesen, Kristian; Mickley, Hans

    2018-05-01

    Data outlining the mortality and the causes of death in patients with type 1 myocardial infarction, type 2 myocardial infarction, and those with myocardial injury are limited. During a 1-year period from January 2010 to January 2011, all hospitalized patients who had cardiac troponin I measured on clinical indication were prospectively studied. Patients with at least one cardiac troponin I value >30 ng/L underwent case ascertainment and individual evaluation by an experienced adjudication committee. Patients were classified as having type 1 myocardial infarction, type 2 myocardial infarction, or myocardial injury according to the criteria of the universal definition of myocardial infarction. Follow-up was ensured until December 31, 2014. Data on mortality and causes of death were obtained from the Danish Civil Registration System and the Danish Register of Causes of Death. Overall, 3762 consecutive patients were followed for a mean of 3.2 years (interquartile range 1.3-3.6 years). All-cause mortality differed significantly among categories: Type 1 myocardial infarction 31.7%, type 2 myocardial infarction 62.2%, myocardial injury 58.7%, and 22.2% in patients with nonelevated troponin values (log-rank test; P causes, vs 42.6% in patients with type 2 myocardial infarction (P = .015) and 41.2% in those with myocardial injury (P causes of death did not differ substantially between patients with type 2 myocardial infarction and those with myocardial injury. Patients with type 2 myocardial infarction and myocardial injury exhibit a significantly higher long-term mortality compared with patients with type 1 myocardial infarction . However, most patients with type 1 myocardial infarction die from cardiovascular causes in contrast to patients with type 2 myocardial infarction and myocardial injury, in whom noncardiovascular causes of death predominate. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Hydrogen Sulfide Donor GYY4137 Protects against Myocardial Fibrosis

    Guoliang Meng

    2015-01-01

    Full Text Available Hydrogen sulfide (H2S is a gasotransmitter which regulates multiple cardiovascular functions. However, the precise roles of H2S in modulating myocardial fibrosis in vivo and cardiac fibroblast proliferation in vitro remain unclear. We investigated the effect of GYY4137, a slow-releasing H2S donor, on myocardial fibrosis. Spontaneously hypertensive rats (SHR were administrated with GYY4137 by intraperitoneal injection daily for 4 weeks. GYY4137 decreased systolic blood pressure and inhibited myocardial fibrosis in SHR as evidenced by improved cardiac collagen volume fraction (CVF in the left ventricle (LV, ratio of perivascular collagen area (PVCA to lumen area (LA in perivascular regions, reduced hydroxyproline concentration, collagen I and III mRNA expression, and cross-linked collagen. GYY4137 also inhibited angiotensin II- (Ang II- induced neonatal rat cardiac fibroblast proliferation, reduced the number of fibroblasts in S phase, decreased collagen I and III mRNA expression and protein synthesis, attenuated oxidative stress, and suppressed α-smooth muscle actin (α-SMA, transforming growth factor-β1 (TGF-β1 expression as well as Smad2 phosphorylation. These results indicate that GYY4137 improves myocardial fibrosis perhaps by a mechanism involving inhibition of oxidative stress, blockade of the TGF-β1/Smad2 signaling pathway, and decrease in α-SMA expression in cardiac fibroblasts.

  12. Scintigraphy for the detection of myocardial damage in the indeterminate form of Chagas disease

    Pedroso, Enio Roberto Pietra; Rezende, Nilton Alves de

    2010-01-01

    Background: non-invasive cardiological methods have been used for the identification of myocardial damage in Chagas disease. Objective: to verify whether the rest/stress myocardial perfusion scintigraphy is able to identify early myocardial damage in the indeterminate form of Chagas disease. Methods: eighteen patients with the indeterminate form of Chagas Disease and the same number of normal controls, paired by sex and age, underwent rest/stress myocardial scintigraphy using sestamibi-99mTc, aiming at detecting early cardiac damage. Results: the results did not show perfusion or ventricular function defects in patients at the indeterminate phase of Chagas disease and in the normal controls, except for a patient who presented signs of ventricular dysfunction in the myocardial perfusion scintigraphy with electrocardiographic gating. Conclusion: the results of this study, considering the small sample size, showed that the rest/stress myocardial scintigraphy using sestamibi-99mTc is not an effective method to detect early myocardial alterations in the indeterminate form of Chagas disease (author)

  13. Scintigraphy for the detection of myocardial damage in the indeterminate form of Chagas disease

    Pedroso, Enio Roberto Pietra; Rezende, Nilton Alves de, E-mail: narezende@terra.com.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Medicina; Abuhid, Ivana Moura [Instituto de Medicina Nuclear e Diagnostico Molecular, Belo Horizonte, MG (Brazil)

    2010-07-15

    Background: non-invasive cardiological methods have been used for the identification of myocardial damage in Chagas disease. Objective: to verify whether the rest/stress myocardial perfusion scintigraphy is able to identify early myocardial damage in the indeterminate form of Chagas disease. Methods: eighteen patients with the indeterminate form of Chagas Disease and the same number of normal controls, paired by sex and age, underwent rest/stress myocardial scintigraphy using sestamibi-99mTc, aiming at detecting early cardiac damage. Results: the results did not show perfusion or ventricular function defects in patients at the indeterminate phase of Chagas disease and in the normal controls, except for a patient who presented signs of ventricular dysfunction in the myocardial perfusion scintigraphy with electrocardiographic gating. Conclusion: the results of this study, considering the small sample size, showed that the rest/stress myocardial scintigraphy using sestamibi-99mTc is not an effective method to detect early myocardial alterations in the indeterminate form of Chagas disease (author)

  14. Clinical study on the time courses of serum myosin light chain I levels in patients with acute myocardial infarction

    Nakanishi, Masako; Saiki, Yasuhiko; Ui, Kazuyo

    1992-01-01

    Changes of serum myosin light chain I (Myosin LCI) concentrations and creatine kinase (CK) activities were serially measured in 23 patients with acute myocardial infarction. Intracoronary thrombolysis was performed in 14 patients (ICT group) while the remaining 9 patients were treated in the conventional manner (non ICT group). The relationships between the maximum levels of serum Myosin LCI or CK and a myocardial infarct size index or left ventricular function were evaluated in 18 patients. The myocardial infarct size index was determined by 201 Tl myocardial scintigrams performed in the chronic phase. Multiple peaks of Myosin LCI were observed in 64% (9/14) of the ICT group and the first peak in 6 of these patients appeared much earlier in the same time as CK peak than in the non-ICT group, while multiple peaks were seen only in one case in the non-ICT group. The infarct size index by 201 Tl myocardial SPECT correlated with maximum Myosin LCI levels (r=0.88, p<0.001, n=10) and CK activities (r=0.67, p<0.05, n=10). These results indicate that the measurement of serum Myosin LCI is very useful for estimating the extent of myocardial damage and suggest that myocardial degeneration occurs at a very early phase of myocardial infarction. (author)

  15. Myocardial imaging in acute myocardial infarction using. beta. -methyl-p-( sup 123 I)-iodophenylpentadecanoic acid; Comparison with sup 201 Tl imaging and wall motion

    Naruse, Hitoshi; Itano, Midoriko; Kondo, Tomohiro (Hyogo College of Medicine, Nishinomiya (Japan)) (and others)

    1992-01-01

    Myocardial imaging using {beta}-methyl-p-({sup 123}I)-iodophenylpentadecanoic acid (BMIPP) was performed in 11 patients with acute myocardial infarction. The left ventricular images were divided into 12 segments, and myocardial images with BMIPP were compared with coronary angiography (CAG), thallium-201 myocardial scintigraphy (Tl) and wall motion obtained by two-dimensional echocardiography (WM). When the culprit lesion was at the proximal point of the left anterior descending artery (LAD), all segments showed depressed uptake. In 3 cases with single vessel disease of the LAD, inferior wall of the basis showed reduced uptake of BMIPP despite the location of the culprit lesion. In cases with discordant uptake between the two tracers, BMIPP frequently showed more severely depressed uptake than Tl in the subacute phase, although the uptake of BMIPP correlated with that of Tl ({tau}=0.82, p<0.001). In such cases, the discordance was related to the improvement in WM from the acute phase to the convalescent phase. BMIPP uptake correlated with WM in the subacute phase ({tau}=0.50, p<0.001). BMIPP showed more severely depressed uptake while WM showed mild asynergy in most cases in which discordance was found between the BMIPP and WM findings. However, there was no correlation between the change in WM from the acute to subacute phases, or the uptakes of BMIPP and Tl alone. We concluded that the myocardial condition can be evaluated in detail in acute myocardial infarction by comparing the findings of BMIPP with those of Tl and WM. (author).

  16. [Myocardial imaging in acute myocardial infarction using beta-methyl-p-(123I)-iodophenylpentadecanoic acid: comparison with 201Tl imaging and wall motion].

    Naruse, H; Itano, M; Kondo, T; Kogame, T; Yamamoto, J; Morita, M; Kawamoto, H; Fukutake, N; Ohyanagi, M; Iwasaki, T

    1992-01-01

    Myocardial imaging using beta-methyl-p-(123I)-iodophenylpentadecanoic acid (BMIPP) was performed in 11 patients with acute myocardial infarction. The left ventricular images were divided into 12 segments, and myocardial imagings with BMIPP were compared with coronary angiography (CAG), thallium-201 myocardial scintigraphy (TL) and wall motion obtained by two-dimensional echocardiography (WM). When the culprit lesion was at the proximal point of the left anterior descending artery (LAD), all segments showed depressed uptake. In 3 cases with single vessel disease of the LAD, inferior wall of the basis showed reduced uptake of BMIPP despite the location of the culprit lesion. In cases with discordant uptake between the two tracers, BMIPP frequently showed more severely depressed uptake than TL in the subacute phase, although the uptake of BMIPP correlated with that of TL (tau = 0.82, p less than 0.001). In such cases, the discordance was related to the improvement in WM from the acute phase to the convalescent phase. BMIPP uptake correlated with WM in the subacute phase (tau = 0.50, p less than 0.001). BMIPP showed more severely depressed uptake while WM showed mild asynergy in most cases in which discordance was found between the BMIPP and WM findings. However, there was no correlation between the change in WM from the acute to subacute phases, or the uptakes of BMIPP and TL alone. We concluded that the myocardial condition can be evaluated in detail in acute myocardial infarction by comparing the findings of BMIPP with those of TL and WM.

  17. The impact of sharps injuries on student nurses: a systematic review.

    Hambridge, Kevin; Nichols, Andrew; Endacott, Ruth

    2016-10-27

    The purpose of this review was to discover the impact of sharps injuries in the student nurse population. Much is known and reported about sharps injuries in registered nurses, but there has been a lack of published evidence regarding sharps injuries within the student nurse population. A systematic review of nursing, health and psychology databases was conducted. The limits set were publications between 1980 and 2014 in the English language. Studies were identified then, following a rigorous critical and quality appraisal with validated tools, were selected for the systematic review. A total of 40 articles met the inclusion criteria, reporting studies conducted in 18 countries. Psychological and physical impacts of sharps injuries in student nurses were reported, such as fear, anxiety and depression, although these impacts were not quantified using a validated instrument. The impact of sharps injuries can be severe, both psychological and physical. This systematic review shows that further research is needed into this, especially in under-researched areas such as the UK, to establish the impact of sharps injuries within this population. Further research would also aid the education and prevention of this harmful problem. The review also emphasises the psychological issues relating to sharps injuries, the impact these can have on individuals and the support and counselling that student nurses require after injury. These findings highlight the potential psychological issues that can result from sharps injuries in this population.

  18. On the sharp front-type solution of the Nagumo equation with ...

    One of the methods is to solve the travelling wave equations and compute an exact solution which describes the sharp travelling wavefront. The second method is to solve numer- ically an initial-moving boundary-value problem for the partial differential equation and obtain an approximation for this sharp front-type solution.

  19. Stability analysis of sharp-boundary Vlasov-fluid screw-pinch equilibria

    Lewis, H.R.; Turner, L.

    1975-01-01

    The Vlasov-fluid model is being used to study the linear stability of sharp-boundary screw pinches numerically. The numerical method appears to work well, and some preliminary results are reported. The sharp-boundary calculation is useful for gaining insight and for comparing with known MHD results. (auth)

  20. Imaging techniques for myocardial inflammation

    O'Connell, J.B.; Henkin, R.E.; Robinson, J.A.

    1986-01-01

    Dilated cardiomyopathy (DC) represents a heterogeneous group of disorders which results in morbidity and mortality in young individuals. Recent evidence suggests that a subset of these patients have histologic evidence of myocarditis which is potentially treatable with immunosuppression. The identification of myocardial inflammation may therefore lead to development of therapeutic regimens designed to treat the cause rather than the effect of the myocardial disease. Ultimately, this may result in improvement in the abysmal prognosis of DC. The currently accepted technique for identification of active myocardial inflammation is endomyocardial biopsy. This technique is not perfect, however, since pathologic standards for the diagnosis of myocarditis have not been established. Furthermore, focal inflammation may give rise to sampling error. The inflammation-avid radioisotope gallium-67 citrate has been used as an adjunct to biopsy improving the yield of myocarditis from 7 percent to 36 percent. Serial imaging correlates well to biopsy results. Future studies are designed to study the applicability of lymphocyte labelling techniques to myocardial inflammatory disease

  1. Dosimetry in myocardial perfusion imaging

    Toledo, Janine M.; Trindade, Bruno; Ribeiro, Tarcisio P.C. [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte (Brazil). Dept. de Engenharia Nuclear. Programa de Pos-Graduacao em Ciencias e Tecnicas Nucleares

    2011-07-01

    This paper conducts a dosimetric investigation on the myocardial perfusion image protocol, together with a literature reviewing, motivated by the significant statistic increasing on mortality, morbidity and disability associated with cardiovascular disease, surpassing infectious diseases. Nuclear Cardiology plays a role n the diagnostic functional evaluation of the heart and in the prognostic of patients with suspected or known cardiac ischemia. In the context of unstable myocardial ischemic syndrome, myocardial perfusion scintigraphy is a non-invasive procedure performed by administering a radiopharmaceutical targeted to the heart. As tool for this study are that the images obtained by thoracic angiotomography and abdominal aorta as a anatomic and functional information for model reproduction in SISCODES - System of Codes for Absorbed Dose Calculations based on Stochastic Methods. Data were manipulated in order to create a voxel computational model of the heart to be running in MCNP - Monte Carlo Neutron Particle Code. . It was assumed a homogeneous distribution of Tl-201 in cardiac muscle. Simulations of the transport of particles through the voxel and the interaction with the heart tissue were performed. As a result, the isodose curves in the heart model are displayed as well as the dose versus volume histogram of the heart muscle. We conclude that the present computational tools can generate doses distributed in myocardial perfusion. (author)

  2. Dosimetry in myocardial perfusion imaging

    Toledo, Janine M.; Trindade, Bruno; Ribeiro, Tarcisio P.C.

    2011-01-01

    This paper conducts a dosimetric investigation on the myocardial perfusion image protocol, together with a literature reviewing, motivated by the significant statistic increasing on mortality, morbidity and disability associated with cardiovascular disease, surpassing infectious diseases. Nuclear Cardiology plays a role n the diagnostic functional evaluation of the heart and in the prognostic of patients with suspected or known cardiac ischemia. In the context of unstable myocardial ischemic syndrome, myocardial perfusion scintigraphy is a non-invasive procedure performed by administering a radiopharmaceutical targeted to the heart. As tool for this study are that the images obtained by thoracic angiotomography and abdominal aorta as a anatomic and functional information for model reproduction in SISCODES - System of Codes for Absorbed Dose Calculations based on Stochastic Methods. Data were manipulated in order to create a voxel computational model of the heart to be running in MCNP - Monte Carlo Neutron Particle Code. . It was assumed a homogeneous distribution of Tl-201 in cardiac muscle. Simulations of the transport of particles through the voxel and the interaction with the heart tissue were performed. As a result, the isodose curves in the heart model are displayed as well as the dose versus volume histogram of the heart muscle. We conclude that the present computational tools can generate doses distributed in myocardial perfusion. (author)

  3. Maintaining knife sharpness in industrial meat cutting: A matter of knife or meat cutter ability.

    Karltun, J; Vogel, K; Bergstrand, M; Eklund, J

    2016-09-01

    Knife sharpness is imperative in meat cutting. The aim of this study was to compare the impact of knife blade steel quality with meat cutters' individual ability to maintain the cutting edge sharp in an industrial production setting. Twelve meat cutters in two different companies using three different knives during normal production were studied in this quasi-experimental study. Methods included were measuring knife cutting force before and after knife use, time knives were used, ratings of sharpness and discomfort and interviews. Results showed that the meat cutters' skill of maintaining sharpness during work had a much larger effect on knife sharpness during work than the knife steel differences. The ability was also related to feelings of discomfort and to physical exertion. It was found that meat cutters using more knives were more likely to suffer from discomfort in the upper limbs, which is a risk for developing MSD. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Myocardial contusion following nonfatal blunt chest trauma

    Kumar, S.A.; Puri, V.K.; Mittal, V.K.; Cortez, J.

    1983-01-01

    Currently available diagnostic techniques for myocardial contusion following blunt chest trauma were evaluated. We investigated 30 patients prospectively over a period of 1 year for the presence of myocardial contusion. Among the 30 patients, eight were found to have myocardial contusion on the basis of abnormal electrocardiograms, elevated creatine phosphokinase MB fraction (CPK-MB), and positive myocardial scan. Myocardial scan was positive in seven of eight patients (87.5%). CPK-MB fraction was elevated in four of eight patients (50%). Definitive electrocardiographic changes were seen in only two of eight patients (25%). It appears that myocardial scan using technetium pyrophosphate and CPK-MB fraction determinations are the most reliable aids in diagnosis of myocardial contusion following blunt chest trauma

  5. Effect of collateral circulation on myocardial protection in patients with acute myocardial infarction. Comparison of technetium-99m-tetrofosmin myocardial single photon emission computed tomography and coronary angiography

    Yoshida, Michi; Kondo, Makoto; Abe, Yoshiteru; Kubota, Tomoyuki; Matsuoka, Ryota; Araki, Makoto; Tanio, Hitoshi; Doyama, Kiyoshi

    2006-01-01

    Evaluation of myocardial blood flow from collateral vessels into the infarct area has been estimated by coronary angiography. In patients with acute myocardial infarction with Thrombolysis in Myocardial Infarction (TIMI) 0 flow, myocardial tracer uptake on single photon emission computed tomography (SPECT) images can predict the collateral blood flow in the infarct area if technetium (Tc)-99m-tetrofosmin was administered before recanalization. The present study investigated whether collateral blood flow evaluated by myocardial scintigraphy is a good predictor of myocardial salvage in patients with acute myocardial infarction. The study group consisted of 30 patients (mean age 65±14 years, 23 males, 7 females) with first acute myocardial infarction and coronary angiography evidence of total occlusion (TIMI 0) within 12 hr after the onset. All patients had one vessel disease related to infarction and TIMI 3 flow after percutaneous coronary intervention (PCI). Tc-99m-tetrofosmin was injected intravenously before the PCI. The regional severity score index (RSSI) was obtained from SPECT using the 17 segment method with the four-point scoring system. Myocardial viability was evaluated by the RSSI obtained from thallium-glucose-insulin infusion SPECT after 1 week and regional wall motion score index obtained from echocardiography during the chronic phase. The patients were divided into two groups according to the angiographic collateral finding. There were no differences in RSSI on thallium-glucose-insulin SPECT and regional wall motion score between the good collateral group (n=8) and poor collateral group (n=22). Myocardial Tc-99m-tetrofosmin RSSI was similar in these groups. On the other hand, the patients were divided according to Tc-99m-tetrofosmin scintigraphic evaluation before PCI. RSSI on thallium-glucose-insulin SPECT was significantly greater (0.7±0.5 vs 1.5±0.4, p<0.01) and regional wall motion score was significantly less (1.46±0.50 vs 2.08±0.78, p<0

  6. Insulin stimulates the expression of the SHARP-1 gene via multiple signaling pathways.

    Takagi, K; Asano, K; Haneishi, A; Ono, M; Komatsu, Y; Yamamoto, T; Tanaka, T; Ueno, H; Ogawa, W; Tomita, K; Noguchi, T; Yamada, K

    2014-06-01

    The rat enhancer of split- and hairy-related protein-1 (SHARP-1) is a basic helix-loop-helix transcription factor. An issue of whether SHARP-1 is an insulin-inducible transcription factor was examined. Insulin rapidly increased the level of SHARP-1 mRNA both in vivo and in vitro. Then, signaling pathways involved with the increase of SHARP-1 mRNA by insulin were determined in H4IIE rat hepatoma cells. Pretreatments with LY294002, wortmannin, and staurosporine completely blocked the induction effect, suggesting the involvement of both phosphoinositide 3-kinase (PI 3-K) and protein kinase C (PKC) pathways. In fact, overexpression of a dominant negative form of atypical protein kinase C lambda (aPKCλ) significantly decreased the induction of the SHARP-1 mRNA. In addition, inhibitors for the small GTPase Rac or Jun N-terminal kinase (JNK) also blocked the induction of SHARP-1 mRNA by insulin. Overexpression of a dominant negative form of Rac1 prevented the activation by insulin. Furthermore, actinomycin D and cycloheximide completely blocked the induction of SHARP-1 mRNA by insulin. Finally, when a SHARP-1 expression plasmid was transiently transfected with various reporter plasmids into H4IIE cells, the promoter activity of PEPCK reporter plasmid was specifically decreased. Thus, we conclude that insulin induces the SHARP-1 gene expression at the transcription level via a both PI 3-K/aPKCλ/JNK- and a PI 3-K/Rac/JNK-signaling pathway; protein synthesis is required for this induction; and that SHARP-1 is a potential repressor of the PEPCK gene expression. © Georg Thieme Verlag KG Stuttgart · New York.

  7. Myocardial imaging with cesium-130

    Harper, P.V.; Resnekov, L.; Stark, V.; Odeh, N.

    1984-01-01

    Recently comparative studies using nitrogen-13 ammonia and cesium-130 have shown strikingly different myocardial localization patterns in the same subjects with ischemic heart disease. Initial localization of ammonia, an avidly extracted agent, reflects the perfusion pattern in viable myocardial tissue. The myocardial localization of cesium ion, taking place more slowly over 15 to 20 minutes, is apparently much less flow dependent, causing uptake defects shown with ammonia to be largely filled in. Cesium thus appears to provide information on the extent of the viable myocardial mass, apart from perfusion. Cesium-130 (t1/2 30 m) decays by positron emission and electron capture. The whole body radiation absorbed dose, assuming uniform distribution, is 24 mrad/mCi. While abundant production of Cs-130 results from proton bombardment of natural xenon [Xe-130(rho,n)Cs-130] at 15 MeV, small amounts of Cs-129, -131, and -132 are also produced, and enriched Xe-130 is not available. Alternatively almost completely uncontaminated Cs-130 is available by alpha bombardment of natural I-127. Anhydrous sodium iodide is dissolved in acetone and a thin layer (≅20 mg per centimeter squared) is evaporated onto the gold plated tip of the internal target backing which is oscillated vertically to spread out the area upon which the beam is incident. The target surface is inclined 2.5 degrees to the beam giving a power density of about 400 watts per centimeter squared at 100μA which is adequately handled by water cooling. A 30-minute bombardment yields 4 to 5 mCi of Cs-130 which is dissolved directly from the target. This approach appears to offer a new and helpful method for evaluating ischemic heart disease by permitting evaluation of viable myocardial mass

  8. Myocardial ischemia in Kawasaki disease

    Fukuda, Tsuyoshi

    1993-01-01

    The detection of myocardial ischemia is essential for evaluation of patients with Kawasaki disease, especially who have had coronary artery lesions. To evaluate the clinical efficacy of Tl-201 single photon emission computed tomography (SPECT) after dipyridamole infusion (maximum dose 0.70 mg/kg) for detecting myocardial ischemia, 44 patients with Kawasaki disease aged 7.7±4.8 years at the study and 10 age matched controls were observed. In the Kawasaki disease group, significant coronary artery stenosis was observed in 14, coronary aneurysm without stenosis in 18, the regression of the coronary aneurysms in 2 and without coronary lesions in 10 patients. In 24 of 44 patients, treadmill exercise stress test was also performed at the same period. Myocardial ischemic changes were observed in 11 patients, all combined with significant coronary artery stenosis. The sensitivity of SPECT for detection of overall coronary stenosis was 79%, coronary that of treadmill exercise test was only 33% (p<0.001). Furthermore, among the patients having significant coronary stenosis, the severity score was significantly elevated in patients who had electrocardiographic abnormal Q wave compared to those without abnormal Q wave (51.0±38.8 versus 20.0±12.1, p<0.05). These data suggest that the pharmacological stress scintigraphy using dipyridamole injection provides not only the accurate detection but quantitative evaluation of myocardial ischemia in these patients. This noninvasive technique may become one of the most useful index for detection and follow-up of myocardial ischemia in Kawasaki disease. (author)

  9. Myocardial ischemia and angina pectoris

    Selwyn, A.P.; Fox, K.M.; Jonathan, A.; Lavender, P.; Watson, I.

    1981-01-01

    Ambulatory monitoring of ST segment changes was performed in 60 patients presenting with angina, positive ECG stress tests and coronary artery disease, 85% of ischemic ECG events were asymptomatic, 37% occurred with no increase in heart rate and 15% of episodes either lasted 20 minutes or more or fluctuated in severity. A controlled pilot study in ten patients showed depression. Radionuclide studies in 50 patients with angina and coronary artery disease have shown that stress (i.e., atrial pacing) produced different patterns of disturbed regional myocardial perfusion related to the patient's exercise capacity and eventually leading to a decrease in regional myocardial perfusion during the ischemic episode. ST segment depression appeared only after the decrease in regional myocardial perfusion. These findings combined with past research suggest that patients with angina and coronary artery disease can suffer frequent asymptomatic disturbances of the regional myocardial perfusion. The frequency of these episodes and the time course for the recovery of the metabolic consequences mean that segments of ventricular myocardium may be constantly abnormal. The relative importance of changes in coronary tone and malfunction of platelets in the diseased coronary tree needs to be examined in clinical research. Pilot studies of antiplatelet agents have shown a significant beneficial effect on episodes of ischemia occurring at night and those occurring without any increase in heart rate. The techniques and observations in these patients with coronary artery disease all suggest that acute transient regional myocardial ischemia is caused by a variety of mechnisms. Further research using objective methods is required to discover the causes of ischemia and to rationalize treatment. (orig./MG) [de

  10. Radioiodinated tracers for myocardial imaging

    Kulkarni, P.V.; Corbett, J.R.

    1990-01-01

    Recent advances in the efficient production of high purity radioiodine (123I) and new efficient radiolabeling techniques have allowed the development of new classes of cardiovascular radiopharmaceuticals. These include 123I-labeled fatty acids to assess myocardial metabolism, 123I-metaiodobenzylguanidine (MIBG) for myocardial neuronal activity, labeled monoclonal antibodies for myocardial necrosis, and labeled lipoproteins for receptor concentration. 123I-labeled fatty acids and MIBG are under clinical investigation with encouraging results. 123I- and 111In-labeled fragments of monoclonal antibodies to myosin have been used for imaging myocardial necrosis in humans. The development of radiotracers for imaging of cholinergic and adrenergic receptors is still in the experimental stage. Recent advances in imaging instrumentation and radiopharmaceuticals have resulted in cardiac imaging applications beyond blood pool ventriculography, perfusion, and infarct-avid imaging. Developments of radioiodine (123I)-labeled agents promise to play an important role in the assessment of myocardial metabolism, neuronal activity, and receptor concentration. The chemistry of iodine is well defined compared with that of 99mTc; therefore, iodine isotopes are well suited for labeling biologically important molecules. Among the iodine isotopes, 123I has nearly ideal nuclear properties for nuclear medical applications with a 13.3-hour half-life (T1/2) and 159 keV gamma emission (83%). Despite the nearly ideal chemical and nuclear properties of 123I, the widespread application of 123I-based radiopharmaceuticals in clinical practice has been limited by high production costs (123I is produced in a cyclotron), relatively limited availability, and the presence of undesirable radionuclidic impurities (124I, T1/2 = 4.2 days; 125I, T1/2 = 60 days; 126I, T1/2 = 13.1 days). 77 references

  11. Study of thallium scintigraphy for myocardial infarction performed within 72 hours of attack

    Setsuda, Koichi; Tomita, Yoshifumi; Takayama, Morimasa (Nippon Medical School, Tokyo)

    1983-11-01

    In 40 cases undergoing /sup 201/Tl myocardial scanning within 72 hours of attack of myocardial infarction, a significant correlation was found between the infarct size determined by myocardial scanning and the size of the infarction estimated on the basis of ECG findings and serum enzymes. The group with high pulmonary capillary wedge pressure was the group with low Tl scores. The group showing dyskinesis and aneurysm in left ventriculography showed low Tl scores and a significant correlation between the ejection fraction calculated from left ventriculograms and the Tl score. The above date indicate that /sup 201/Tl myocardial scanning in the acute phase after attack of infarction reflects the infarction size and cardiac function.

  12. Left anterior descending coronary artery myocardial bridging by multislice computed tomography: Correlation with clinical findings

    Jodocy, Daniel; Aglan, Iman; Friedrich, Guy; Mallouhi, Ammar; Pachinger, Otmar; Jaschke, Werner; Feuchtner, Gudrun M.

    2010-01-01

    Objective: To assess the relationship between left anterior descending (LAD) coronary artery myocardial bridging detected by 64-slice computed tomography (CT) and clinical findings. Methods: 221 consecutive patients were examined with coronary 64-slice CT angiography. 21 patients with coronary stenosis >50% were excluded. The length, depth, and luminal narrowing of LAD myocardial bridges during systole and diastole were measured. CT findings were compared with the treadmill ECG-stress test, and clinical symptoms. Results: Myocardial bridges of the LAD were found in 23% of patients (51/221) (length, 14.9 ± 6.5 mm; depth, 2.6 ± 1.6 mm). A significant difference was noted between the LAD luminal diameter before the intramyocardial course and intramyocardially, for both diastole and systole (p 50% was found in 3/25 (8%). 30/51 (59%) of bridges were 'deep' (>2 mm myocardial depth), 21/51 (41%) were 'superficial'. The prevalence of a positive ECG-stress tests for the anterior myocardial region was significantly higher in patients with LAD myocardial bridges (34/50; 68%) compared to those without (28/144; 19.4%) (p < 0.001). There was no difference between 'superficial' and 'deep' LAD myocardial bridges in regard to a positive treadmill ECG-stress test. Typical angina was rare with 6%. Conclusion: LAD myocardial bridges are common findings and can possibly explain a positive exercise ECG-stress test for anterior myocardial ischemia. Intramyocardial LAD segments show mild-to-moderate luminal narrowing at rest, which is higher during end-systolic phase.

  13. Left anterior descending coronary artery myocardial bridging by multislice computed tomography: Correlation with clinical findings

    Jodocy, Daniel; Aglan, Iman [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Friedrich, Guy [Clinical Department of Cardiology, Innsbruck Medical University, Innsbruck (Austria); Mallouhi, Ammar [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Pachinger, Otmar [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Clinical Department of Cardiology, Innsbruck Medical University, Innsbruck (Austria); Jaschke, Werner [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Feuchtner, Gudrun M. [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria)], E-mail: gudrun.feuchtner@i-med.ac.at

    2010-01-15

    Objective: To assess the relationship between left anterior descending (LAD) coronary artery myocardial bridging detected by 64-slice computed tomography (CT) and clinical findings. Methods: 221 consecutive patients were examined with coronary 64-slice CT angiography. 21 patients with coronary stenosis >50% were excluded. The length, depth, and luminal narrowing of LAD myocardial bridges during systole and diastole were measured. CT findings were compared with the treadmill ECG-stress test, and clinical symptoms. Results: Myocardial bridges of the LAD were found in 23% of patients (51/221) (length, 14.9 {+-} 6.5 mm; depth, 2.6 {+-} 1.6 mm). A significant difference was noted between the LAD luminal diameter before the intramyocardial course and intramyocardially, for both diastole and systole (p < 0.001); with a higher diameter reduction of 27% for end-systole compared to end-diastole with 15% (p = 0.006). Systolic LAD intramyocardial luminal narrowing >50% was found in 3/25 (8%). 30/51 (59%) of bridges were 'deep' (>2 mm myocardial depth), 21/51 (41%) were 'superficial'. The prevalence of a positive ECG-stress tests for the anterior myocardial region was significantly higher in patients with LAD myocardial bridges (34/50; 68%) compared to those without (28/144; 19.4%) (p < 0.001). There was no difference between 'superficial' and 'deep' LAD myocardial bridges in regard to a positive treadmill ECG-stress test. Typical angina was rare with 6%. Conclusion: LAD myocardial bridges are common findings and can possibly explain a positive exercise ECG-stress test for anterior myocardial ischemia. Intramyocardial LAD segments show mild-to-moderate luminal narrowing at rest, which is higher during end-systolic phase.

  14. A sharp interface Cartesian grid method for viscous simulation of shocked particle-laden flows

    Das, Pratik; Sen, Oishik; Jacobs, Gustaaf; Udaykumar, H. S.

    2017-09-01

    A Cartesian grid-based sharp interface method is presented for viscous simulations of shocked particle-laden flows. The moving solid-fluid interfaces are represented using level sets. A moving least-squares reconstruction is developed to apply the no-slip boundary condition at solid-fluid interfaces and to supply viscous stresses to the fluid. The algorithms developed in this paper are benchmarked against similarity solutions for the boundary layer over a fixed flat plate and against numerical solutions for moving interface problems such as shock-induced lift-off of a cylinder in a channel. The framework is extended to 3D and applied to calculate low Reynolds number steady supersonic flow over a sphere. Viscous simulation of the interaction of a particle cloud with an incident planar shock is demonstrated; the average drag on the particles and the vorticity field in the cloud are compared to the inviscid case to elucidate the effects of viscosity on momentum transfer between the particle and fluid phases. The methods developed will be useful for obtaining accurate momentum and heat transfer closure models for macro-scale shocked particulate flow applications such as blast waves and dust explosions.

  15. Study progress of cardiac MRI technology in assessment of myocardial viability after myocardial infarction

    Wang Jing; Zhang Hao

    2013-01-01

    Acute myocardial infarction (AMI) is one of the most common diseases that cause disability and death around the world. Correctly and effectively assessing the myocardial viability after myocardial infarction can reduce the disabled rate and mortality rate. At present, many methods could be used to assess myocardial viability. The cardiac magnetic resonance imaging (CMR) technology has a lot of advantages compared to other methods. In this paper, we reviewed the research progress of CMR in assessment of myocardial viability after myocardial infarction, and compared CMR with other technologies. (authors)

  16. Evaluation of left ventricular function in patient with old myocardial infarction by 201-thallium myocardial scintigraphy

    Takahashi, Kanji; Shimohara, Yasuaki; Ito, Misao; Okada, Keisei [Kure Kyosai Hospital, Hiroshima (Japan); Kodama, Kazunori

    1984-08-01

    Correlation between the ratio of myocardial defect calculated by 201-thallium myocardial scintigraphy and the left ventricular ejection fraction (LVEF) obtained by gated blood pool scintigraphy and the maximum level of creatine phosphokinase (CPK) was studied in 70 patients with old myocardial infarction. There was a significant correlation between the defect ratio and the LVEF or CPK level in patients with anterior or septal myocardial infarction. In all patients with inferior myocardial infarction in whom no defect was seen, the LVEF was more than 40%. However, no distinct correlation between the defect ratio and the LVEF or CPK level was obtained in cases of inferior myocardial infarction.

  17. Edge Sharpness Assessment by Parametric Modeling: Application to Magnetic Resonance Imaging.

    Ahmad, R; Ding, Y; Simonetti, O P

    2015-05-01

    In biomedical imaging, edge sharpness is an important yet often overlooked image quality metric. In this work, a semi-automatic method to quantify edge sharpness in the presence of significant noise is presented with application to magnetic resonance imaging (MRI). The method is based on parametric modeling of image edges. First, an edge map is automatically generated and one or more edges-of-interest (EOI) are manually selected using graphical user interface. Multiple exclusion criteria are then enforced to eliminate edge pixels that are potentially not suitable for sharpness assessment. Second, at each pixel of the EOI, an image intensity profile is read along a small line segment that runs locally normal to the EOI. Third, the profiles corresponding to all EOI pixels are individually fitted with a sigmoid function characterized by four parameters, including one that represents edge sharpness. Last, the distribution of the sharpness parameter is used to quantify edge sharpness. For validation, the method is applied to simulated data as well as MRI data from both phantom imaging and cine imaging experiments. This method allows for fast, quantitative evaluation of edge sharpness even in images with poor signal-to-noise ratio. Although the utility of this method is demonstrated for MRI, it can be adapted for other medical imaging applications.

  18. Evaluation of Effects of Warning Sign Position on Driving Behavior in Horizontal Sharp Curves

    Xiao-hua Zhao

    2015-02-01

    Full Text Available In present time, the guidelines on warning sign position in the China National Standard lack detailed and standard regulations of placing warning signs on sharp curves, which may cause road safety problems. Therefore, this paper briefly discussed how to optimize the position of a warning sign on a sharp curve through a driving simulator experiment. This study concluded that a warning sign placed at different positions prior to a sharp curve will have different influence ranges for drivers approaching and negotiating the curve. Meanwhile, different positions of a warning sign imposed different effect obviously on the adjustment of vehicle's lane position on sharp curves with the same radius, especially at the midpoint of a sharp curve. The evaluation results of five positions (0 m, 50 m, 100 m, 200 m, and 400 m in advance showed that only when the warning signs were placed 100 m or 200 m prior to sharp curves, can they achieve positive influence on driving behavior. On this basis, the authors look forward to providing rationalization proposals in selecting the best position of a warning sign on a sharp curve for the engineering implementation and national standard.

  19. Super-Sharp Radio 'Eye' Remeasuring the Universe

    2011-02-01

    Using the super-sharp radio "vision" of astronomy's most precise telescope, scientists have extended a directly-measured "yardstick" three times farther into the cosmos than ever before, an achievement with important implications for numerous areas of astrophysics, including determining the nature of Dark Energy, which constitutes 70 percent of the Universe. The continent-wide Very Long Baseline Array (VLBA) also is redrawing the map of our home Galaxy and is poised to yield tantalizing new information about extrasolar planets, among many other cutting-edge research projects. The VLBA provides the greatest ability to see fine detail, called resolving power, of any telescope in the world. It can produce images hundreds of times more detailed than those from the Hubble Space Telescope -- power equivalent to sitting in New York and reading a newspaper in Los Angeles. This power allows astronomers to make precise cosmic measurements with far-ranging implications for research within our own Galaxy and far beyond. New measurements with the VLBA have placed a galaxy called NGC 6264 at a distance of 450 million light-years from Earth, with an uncertainty of no more than 9 percent. This is the farthest distance ever directly measured, surpassing a measurement of 160 million light-years to another galaxy in 2009. Previously, distances beyond our own Galaxy have been estimated through indirect methods. "Our direct, geometric measurements are independent of the assumptions and complications inherent in other techniques," said James Braatz, of the National Radio Astronomy Observatory (NRAO), who worked with Cheng-Yu Kuo, of the University of Virginia and NRAO. Fine-tuning the measurement of ever-greater distances is vital to determining the expansion rate of the Universe, which helps theorists narrow down possible explanations for the nature of Dark Energy. Different models of Dark Energy predict different values for the expansion rate, known as the Hubble Constant. "Solving

  20. Sharp vorticity gradients in two-dimensional turbulence and the energy spectrum

    Kuznetsov, E.A.; Naulin, Volker; Nielsen, Anders Henry

    2010-01-01

    Formation of sharp vorticity gradients in two-dimensional (2D) hydrodynamic turbulence and their influence on the turbulent spectra are considered. The analog of the vortex line representation as a transformation to the curvilinear system of coordinates moving together with the di-vorticity lines...... is developed and compressibility of this mapping appears as the main reason for the formation of the sharp vorticity gradients at high Reynolds numbers. In the case of strong anisotropy the sharp vorticity gradients can generate spectra which fall off as k −3 at large k, which appear to take the same form...

  1. Testing the efficiency of the wine market using unit root tests with sharp and smooth breaks

    Elie Bouri

    2017-12-01

    Full Text Available This paper examines the efficient market hypothesis for the wine market using a novel unit root test while accounting for sharp shifts and smooth breaks in the monthly data. We find evidence of structural shifts and nonlinearity in the wine indices. Contrary to the results from conventional linear unit root tests, when we account for sharp shifts and smooth breaks, the unit root null for each of the wine indices has been rejected. Overall, our results suggest that the wine market is inefficient when we incorporate breaks. We provide some practical and policy implications of our findings. Keywords: Wine market, Efficiency, Sharp and smooth breaks, Unit root tests

  2. 13N-Ammonia pet-derived ventricular synchrony correlates with myocardial perfusion reserve better than left ventricular ejection fraction : A study in infarcted patients

    Juarez-Orozco, Luis Eduardo; Slart, Riemer; Tio, Rene A.; Inarra-Talboy, Fernando; Monroy, Andrea; Ayala-German, AnaGabriela; Dierckx, Rudi A.; Rosas, Erick Alexanderson

    2016-01-01

    Background: PET myocardial perfusion allows myocardial perfusion reserve (MPR) quantification as well as left ventricular ejection fraction (LVEF) and synchrony estimation through phase analysis. There is a relationship between MPR and LVEF and both have proven prognostic value in coronary artery

  3. Myocardial perfusion modeling using MRI

    Larsson, H B; Fritz-Hansen, T; Rostrup, Egill

    1996-01-01

    In the present study, it is shown that it is possible to quantify myocardial perfusion using magnetic resonance imaging in combination with gadolinium diethylenetriaminopentaacetic acid (Gd-DTPA). Previously, a simple model and method for measuring myocardial perfusion using an inversion recovery...... turbo-FLASH (fast low-angle shot) sequence and Gd-DTPA has been presented. Here, an extension of the model is presented taking into account fast and slow water exchange between the compartments, enabling the calculation of the unidirectional influx constant (Ki) for Gd-DTPA, the distribution volume...... of Gd-DTPA (lambda), the vascular blood volume (Vb), and the time delay through the coronary arteries (delta T). The model was evaluated by computer simulation and used on experimental results from seven healthy subjects. The results in the healthy volunteers for a region of interest placed...

  4. Functional tests for myocardial ischemia

    Levinson, J.R.; Guiney, T.E.; Boucher, C.A.

    1991-01-01

    Functional tests for myocardial ischemia are numerous. Most depend upon a combination of either exercise or pharmacologic intervention with analysis of the electrocardiogram, of regional perfusion with radionuclide imaging, or of regional wall motion with radionuclide imaging or echocardiography. While each test has unique features, especially at the research level, they are generally quite similar in clinical practice, so the clinician is advised to concentrate on one or two in which local expertise is high.22 references

  5. Cardiac MRI for myocardial ischemia.

    Daly, Caroline

    2013-01-01

    Proper assessment of the physiologic impact of coronary artery stenosis on the LV myocardium can affect patient prognosis and treatment decisions. Cardiac magnetic resonance imaging (CMR) assesses myocardial perfusion by imaging the myocardium during a first-pass transit of an intravenous gadolinium bolus, with spatial and temporal resolution substantially higher than nuclear myocardial perfusion imaging. Coupled with late gadolinium enhancement (LGE) imaging for infarction during the same imaging session, CMR with vasodilating stress perfusion imaging can qualitatively and quantitatively assess the myocardial extent of hypoperfusion from coronary stenosis independent of infarcted myocardium. This approach has been validated experimentally, and multiple clinical trials have established its diagnostic robustness when compared to stress single-photon emission computed tomography. In specialized centers, dobutamine stress CMR has been shown to have incremental diagnostic value above stress echocardiography due to its high imaging quality and ability to image the heart with no restriction of imaging window. This paper reviews the technical aspects, diagnostic utility, prognostic values, challenges to clinical adaptation, and future developments of stress CMR imaging.

  6. Jasper Sharp - mees, kes jättis varasema töö, et vaadata Jaapani filme / Jasper Sharp ; intervjueerinud Helen Merila

    Sharp, Jasper, 1971-

    2011-01-01

    Euroopa kultuuripealinn Tallinn 2011 programmi osana ning koostöös Zipangu Fest'iga korraldatakse Tallinna Kinomajas 25.-28. aug.-ni Aasia sõltumatute filmide festival EVA - East via Asia. Festivali kuraator, veebisaidi Midnight Eye kaastoimetaja Jasper Sharp endast, festivalist, Jaapani sõltumatust kinost tänapäeval. Festivali kava

  7. Quadrilateral mesh fitting that preserves sharp features based on multi-normals for Laplacian energy

    Yusuke Imai

    2014-04-01

    Full Text Available Because the cost of performance testing using actual products is expensive, manufacturers use lower-cost computer-aided design simulations for this function. In this paper, we propose using hexahedral meshes, which are more accurate than tetrahedral meshes, for finite element analysis. We propose automatic hexahedral mesh generation with sharp features to precisely represent the corresponding features of a target shape. Our hexahedral mesh is generated using a voxel-based algorithm. In our previous works, we fit the surface of the voxels to the target surface using Laplacian energy minimization. We used normal vectors in the fitting to preserve sharp features. However, this method could not represent concave sharp features precisely. In this proposal, we improve our previous Laplacian energy minimization by adding a term that depends on multi-normal vectors instead of using normal vectors. Furthermore, we accentuate a convex/concave surface subset to represent concave sharp features.

  8. Effects of sharp vorticity gradients in two-dimensional hydrodynamic turbulence

    Kuznetsov, E.A.; Naulin, Volker; Nielsen, Anders Henry

    2007-01-01

    The appearance of sharp vorticity gradients in two-dimensional hydrodynamic turbulence and their influence on the turbulent spectra are considered. We have developed the analog of the vortex line representation as a transformation to the curvilinear system of coordinates moving together with the ......The appearance of sharp vorticity gradients in two-dimensional hydrodynamic turbulence and their influence on the turbulent spectra are considered. We have developed the analog of the vortex line representation as a transformation to the curvilinear system of coordinates moving together...... with the divorticity lines. Compressibility of this mapping can be considered as the main reason for the formation of the sharp vorticity gradients at high Reynolds numbers. For two-dimensional turbulence in the case of strong anisotropy the sharp vorticity gradients can generate spectra which fall off as k−3 at large...

  9. Best Way to Get Rid of Used Needles and Other Sharps

    ... other options are not available. If traveling by plane, check the Transportation Security Administration (TSA) website for ... be thrown away in the common trash. Additional Consumer Information How to Get Rid of a Sharps ...

  10. Surface-enhanced Raman scattering on periodic metal nanotips with tunable sharpness

    Linn, Nicholas C; Sun, C-H; Arya, Ajay; Jiang Peng; Jiang Bin

    2009-01-01

    This paper reports on a scalable bottom-up technology for producing periodic gold nanotips with tunable sharpness as surface-enhanced Raman scattering (SERS) substrates. Inverted silicon pyramidal pits, which are templated from non-close-packed colloidal crystals prepared by a spin-coating technology, are used as structural templates to replicate arrays of polymer nanopyramids with nanoscale sharp tips. The deposition of a thin layer of gold on the polymer nanopyramids leads to the formation of SERS-active substrates with a high enhancement factor (up to 10 8 ). The thickness of the deposited metal determines the sharpness of the nanotips and the resulting Raman enhancement factor. Finite-element electromagnetic modeling shows that the nanotips can significantly enhance the local electromagnetic field and the sharpness of nanotips greatly affects the SERS enhancement.

  11. 78 FR 43183 - Notice of Availability for Sharpe Permit Relinquishment Project Environmental Assessment Finding...

    2013-07-19

    ... for Sharpe Permit Relinquishment Project Environmental Assessment Finding of No Significant Impact... Relinquishment Project Environmental Assessment (EA) Finding of No Significant Impact (FONSI). SUMMARY: On April... environment. Human environment was interpreted comprehensively to include the natural and physical environment...

  12. The pattern of sharps injury to health care workers at Witbank Hospital

    800 000 needle stick injuries occur every year.1 According to UK data, there were ... Factors associated with an increased risk of occupational exposure can differ from ... there are many sharps safety devices on the market, but unfortunately.

  13. The close objects buffer : a sharp shadow detection technique for radiosity methods

    Telea, A.C.; Overveld, van C.W.A.M.

    1997-01-01

    Detecting sharp illumination variations such as shadow boundaries is an important problem for radiosity methods. Such illumination variations are captured using a nonuniform mesh that refines the areas exhibiting high illumination gradients. Nonuniform meshing techniques like discontinuity meshing

  14. The Close Objects Buffer : A Sharp Shadow Detection Technique for Radiosity Methods

    Telea, A.C.; Overveld, C.W.A.M. van

    1998-01-01

    Detecting sharp illumination variations such as shadow boundaries is an important problem for radiosity methods. Such illumination variations are captured using a nonuniform mesh that refines the areas exhibiting high illumination gradients. Nonuniform meshing techniques like discontinuity meshing

  15. LLNL contributions to ANL Report ANL/NE-16/6 'Sharp User Manual'

    Solberg, J. M.

    2016-01-01

    Diablo is a Multiphysics implicit finite element code with an emphasis on coupled structural/thermal analysis. In the SHARP framework, it is used as the structural solver, and may also be used as the mesh smoother.

  16. Needles and Other Sharps (Safe Disposal Outside of Health Care Settings)

    ... disorders, and psoriasis. Examples of sharps include: Needles – hollow needles used to inject drugs (medication) under the ... and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993 1-888-INFO-FDA (1-888- ...

  17. Current status of sharps waste management in the lower-level ...

    Key words: Sharps waste management, health facilities, infection, Tanzania ... and hence improve infection prevention and control at work places in Tanzania. .... The UNICEF /WHO safety boxes were observed in 31 (23%) of the LLHFs, while ...

  18. Evaluation of 99mTc-nitroimidazole in animal of myocardial necrosis

    Shimpi, H.H.; Mahapatra, S.; Noronha, O.P.D.

    1998-01-01

    Full text: Extensive studies carried out using 99m Tc-nitroimidazole (BMS 181321) suggested that it is a useful agent to investigate the status of hypoxia in solid tumors and ischemic myocardium. In vitro studies also showed that 99m Tc nitroimidazole is preferentially trapped in and retained by hypoxic, but viable cardiac muscle. We have evaluated the compound in an animal (rat) model of myocardial necrosis. 99m Tc-nitromidazole was labelled with 99m Tc by using cyclan and Sn-glucaric acid. The radiochemical purity was >95%. It was found to be very stable. Experimental (rat) animal of myocardial necrosis or ischemic necrosis was obtained by injecting iso proternol HCl subcutaneously (S.C.) at a dose of 5.25 mg/kg body weight. After 48 h, gross and microscopic necrotic changes were seen in the heart which closely resembled the myocardial infarct of necrotic lesion akin to ischemic necrosis of the myocardium. Animal biodistribution study demonstrated that 99m Tc nitroimidazole cleared very fast from the blood stream of both normal system. Significantly higher uptake was seen in heart of experimental animals compared to normal animals at 60 min. The ratios of heart to blood, liver and kidneys in both normal and experimental animals showed significantly higher ratios in experimental animals. The heart to blood ratio of experimental animal remained same up to 60 min. compared to a sharp decline with time in normal animals. The above results show that 99m Tc-nitroimidazole could be used for detection of myocardial necrosis or myocardial infarct in clinical conditions

  19. A sharp interface model for void growth in irradiated materials

    Hochrainer, Thomas; El-Azab, Anter

    2015-03-01

    A thermodynamic formalism for the interaction of point defects with free surfaces in single-component solids has been developed and applied to the problem of void growth by absorption of point defects in irradiated metals. This formalism consists of two parts, a detailed description of the dynamics of defects within the non-equilibrium thermodynamic frame, and the application of the second law of thermodynamics to provide closure relations for all kinetic equations. Enforcing the principle of non-negative entropy production showed that the description of the problem of void evolution under irradiation must include a relationship between the normal fluxes of defects into the void surface and the driving thermodynamic forces for the void surface motion; these thermodynamic forces are identified for both vacancies and interstitials and the relationships between these forces and the normal point defect fluxes are established using the concepts of transition state theory. The latter theory implies that the defect accommodation into the surface is a thermally activated process. Numerical examples are given to illustrate void growth dynamics in this new formalism and to investigate the effect of the surface energy barriers on void growth. Consequences for phase field models of void growth are discussed.

  20. A faunistic study of genus Chasmogenus Sharp, 1882 of China (Coleoptera, Hydrophilidae

    Fenglong Jia

    2018-02-01

    Full Text Available Chasmogenus Sharp, 1882 is newly reported from the Chinese Mainland. A new species, C. parorbus sp. n., is described from China (Yunnan. Chasmogenus orbus Watanabe, 1987 is reported from Hong Kong, the first record outside Japan. Chasmogenus abnormalis (Sharp, 1890 is reported from the Chinese mainland for the first time. The male genitalia of each species are illustrated. A key to the Chinese species of the genus is provided.

  1. A faunistic study of genus Chasmogenus Sharp, 1882 of China (Coleoptera, Hydrophilidae).

    Jia, Fenglong; Tang, Yu-Dan

    2018-01-01

    Chasmogenus Sharp, 1882 is newly reported from the Chinese Mainland. A new species, C. parorbus sp. n. , is described from China (Yunnan). Chasmogenus orbus Watanabe, 1987 is reported from Hong Kong, the first record outside Japan. Chasmogenus abnormalis (Sharp, 1890) is reported from the Chinese mainland for the first time. The male genitalia of each species are illustrated. A key to the Chinese species of the genus is provided.

  2. Single-step electrochemical method for producing very sharp Au scanning tunneling microscopy tips

    Gingery, David; Buehlmann, Philippe

    2007-01-01

    A single-step electrochemical method for making sharp gold scanning tunneling microscopy tips is described. 3.0M NaCl in 1% perchloric acid is compared to several previously reported etchants. The addition of perchloric acid to sodium chloride solutions drastically shortens etching times and is shown by transmission electron microscopy to produce very sharp tips with a mean radius of curvature of 15 nm

  3. Evaluation of a method to determine the myocardial uptake from 123I-BMIPP myocardial SPECT and its significance

    Iwase, Mikio; Toriyama, Takayuki; Itou, Masato; Shimao, Ryuichiro; Ikeda, Koshiro; Suzuki, Takeshi; Nobuta, Takaaki; Iida, Akihiko.

    1996-01-01

    We examined methods of calculating myocardial uptake (TU) of 123 I-BMIPP by SPECT, and compared TU to heart function (ejection fraction (EF), cardiac output (CO), cardiac index (CI)) calculated by left ventriculography. Forty-two patients with acute myocardial infarction were classified into 5 groups; within 1 week (I), from 1 to 2 weeks (II), from 2 weeks to 1.5 months (III), from 1.5 to 3 months (IV) and more than 3 months (V) after percutaneous transluminal coronary angioplasty (PTCA). Chest depth (Tw) was calculated by measuring the thoracic absorption rate of 123 I. In calculating TU, the myocardial count was calculated from short-axis tomograms, and then absorption was corrected using Tw to calculate each value on early-phase image (E) and delay-phase image (D). The influence of lung uptake on myocardial count was only 1.76%. When TU was compared to heart function, there were correlations between group I and group V. Especially in group VD-TU was a significantly correlated with heart function. In heart function CI, but not EF nor CO, was significantly correlated with TU. It was suggested that the correlation between TU and heart function reflected the infarct condition before PTCA in group I, and that the individual difference in recovery of fatty acid metabolism in group V. The significant correlation between D-TU and CI suggests that D-TU reflects heart function and fatty acid metabolism, although TU is influenced by differences in physical status. (author)

  4. Understanding sharps injuries in home healthcare: The Safe Home Care qualitative methods study to identify pathways for injury prevention.

    Markkanen, Pia; Galligan, Catherine; Laramie, Angela; Fisher, June; Sama, Susan; Quinn, Margaret

    2015-04-11

    Home healthcare is one of the fastest growing sectors in the United States. Percutaneous injuries from sharp medical devices (sharps) are a source of bloodborne pathogen infections among home healthcare workers and community members. Sharps use and disposal practices in the home are highly variable and there is no comprehensive analysis of the system of sharps procurement, use and disposal in home healthcare. This gap is a barrier to effective public health interventions. The objectives of this study were to i) identify the full range of pathways by which sharps enter and exit the home, stakeholders involved, and barriers for using sharps with injury prevention features; and ii) assess the leverage points for preventive interventions. This study employed qualitative research methods to develop two systems maps of the use of sharps and prevention of sharps injuries in home healthcare. Twenty-six in-depth interview sessions were conducted including home healthcare agency clinicians, public health practitioners, sharps device manufacturers, injury prevention advocates, pharmacists and others. Interview transcripts were audio-recorded and analyzed thematically using NVIVO qualitative research analysis software. Analysis of supporting archival material also was conducted. All findings guided development of the two maps. Sharps enter the home via multiple complex pathways involving home healthcare providers and home users. The providers reported using sharps with injury prevention features. However, home users' sharps seldom had injury prevention features and sharps were commonly re-used for convenience and cost-savings. Improperly discarded sharps present hazards to caregivers, waste handlers, and community members. The most effective intervention potential exists at the beginning of the sharps systems maps where interventions can eliminate or minimize sharps injuries, in particular with needleless treatment methods and sharps with injury prevention features

  5. A report on SHARP (Spacecraft Health Automated Reasoning Prototype) and the Voyager Neptune encounter

    Martin, R. G. (Editor); Atkinson, D. J.; James, M. L.; Lawson, D. L.; Porta, H. J.

    1990-01-01

    The development and application of the Spacecraft Health Automated Reasoning Prototype (SHARP) for the operations of the telecommunications systems and link analysis functions in Voyager mission operations are presented. An overview is provided of the design and functional description of the SHARP system as it was applied to Voyager. Some of the current problems and motivations for automation in real-time mission operations are discussed, as are the specific solutions that SHARP provides. The application of SHARP to Voyager telecommunications had the goal of being a proof-of-capability demonstration of artificial intelligence as applied to the problem of real-time monitoring functions in planetary mission operations. AS part of achieving this central goal, the SHARP application effort was also required to address the issue of the design of an appropriate software system architecture for a ground-based, highly automated spacecraft monitoring system for mission operations, including methods for: (1) embedding a knowledge-based expert system for fault detection, isolation, and recovery within this architecture; (2) acquiring, managing, and fusing the multiple sources of information used by operations personnel; and (3) providing information-rich displays to human operators who need to exercise the capabilities of the automated system. In this regard, SHARP has provided an excellent example of how advanced artificial intelligence techniques can be smoothly integrated with a variety of conventionally programmed software modules, as well as guidance and solutions for many questions about automation in mission operations.

  6. Stem cell mobilization induced by subcutaneous granulocyte-colony stimulating factor to improve cardiac regeneration after acute ST-elevation myocardial infarction: result of the double-blind, randomized, placebo-controlled stem cells in myocardial infarction (STEMMI) trial

    Ripa, RS; Jorgensen, E; Wang, Y

    2006-01-01

    BACKGROUND: Phase 1 clinical trials of granulocyte-colony stimulating factor (G-CSF) treatment after myocardial infarction have indicated that G-CSF treatment is safe and may improve left ventricular function. This randomized, double-blind, placebo-controlled trial aimed to assess the efficacy of......: Bone marrow stem cell mobilization with subcutaneous G-CSF is safe but did not lead to further improvement in ventricular function after acute myocardial infarction compared with the recovery observed in the placebo group...

  7. Noninvasive assessment of canine myocardial oxidative metabolism with carbon-11 acetate and positron emission tomography

    Brown, M.A.; Myears, D.W.; Bergmann, S.R.

    1988-01-01

    Noninvasive quantification of regional myocardial metabolism would be highly desirable to evaluate pathogenetic mechanisms of heart disease and their response to therapy. It was previously demonstrated that the metabolism of radiolabeled acetate, a readily utilized myocardial substrate predominantly metabolized to carbon dioxide (CO2) by way of the tricarboxylic acid cycle, provides a good index of oxidative metabolism in isolated perfused rabbit hearts because of tight coupling between the tricarboxylic acid cycle and oxidative phosphorylation. In the present study, in a prelude to human studies, the relation between myocardial clearance of carbon-11 (11C)-labeled acetate and myocardial oxygen consumption was characterized in eight intact dogs using positron emission tomography. Anesthetized dogs were studied during baseline conditions and again during either high or low work states induced pharmacologically. High myocardial extraction and rapid blood clearance of tracer yielded myocardial images of excellent quality. The turnover (clearance) of 11C radioactivity from the myocardium was biexponential with the mean half-time of the dominant rapid phase averaging 5.4 +/- 2.2, 2.8 +/- 1.3 and 11.1 +/- 1.3 min in control, high and low work load studies, respectively. No significant difference was found between the rate of clearance of 11C radioactivity from the myocardium measured noninvasively with positron emission tomography and the myocardial efflux of 11CO2 measured directly from the coronary sinus. The rate of clearance of the 11C radioactivity from the heart correlated closely with myocardial oxygen consumption (r = 0.90, p less than 0.001) as well as with the rate-pressure product (r = 0.95, p less than 0.001). Hence, the rate of oxidation of 11C-acetate can be determined noninvasively with positron emission tomography, providing a quantitative index of oxidative metabolism under diverse conditions

  8. Screening for silent myocardial ischemia caseof diabetics : interest of myocardial perfusion scintigraphy

    Bahri, Haifa

    2007-01-01

    Silent myocardial ischemia is a major cause of morbidity and mortality in diabetic patients. Its diagnosis by noninvasive means such as myocardial SPECT would improve the management of these patients. The purpose of this study is to assess the frequency of silent myocardial ischemia in asymptomatic diabetics and their evolution. As a result, the myocardial SPECT is a reliable tool for screening for silent myocardial ischemia in diabetic patients. Its prognostic value allows to stratify the cardiac risk and guide therapeutic management. Its integration into a screening strategy in Tunisia seems limited by its low availability and cost. The latter could be reduced by better patient selection.

  9. Nanoparticle Stability in Axial InAs-InP Nanowire Heterostructures with Atomically Sharp Interfaces.

    Zannier, Valentina; Rossi, Francesca; Dubrovskii, Vladimir G; Ercolani, Daniele; Battiato, Sergio; Sorba, Lucia

    2018-01-10

    The possibility to expand the range of material combinations in defect-free heterostructures is one of the main motivations for the great interest in semiconductor nanowires. However, most axial nanowire heterostructures suffer from interface compositional gradients and kink formation, as a consequence of nanoparticle-nanowire interactions during the metal-assisted growth. Understanding such interactions and how they affect the growth mode is fundamental to achieve a full control over the morphology and the properties of nanowire heterostructures for device applications. Here we demonstrate that the sole parameter affecting the growth mode (straight or kinked) of InP segments on InAs nanowire stems by the Au-assisted method is the nanoparticle composition. Indeed, straight InAs-InP nanowire heterostructures are obtained only when the In/Au ratio in the nanoparticles is low, typically smaller than 1.5. For higher In content, the InP segments tend to kink. Tailoring the In/Au ratio by the precursor fluxes at a fixed growth temperature enables us to obtain straight and radius-uniform InAs-InP nanowire heterostructures (single and double) with atomically sharp interfaces. We present a model that is capable of describing all the experimentally observed phenomena: straight growth versus kinking, the stationary nanoparticle compositions in pure InAs and InAs-InP nanowires, the crystal phase trends, and the interfacial abruptness. By taking into account different nanowire/nanoparticle interfacial configurations (forming wetting or nonwetting monolayers in vertical or tapered geometry), our generalized model provides the conditions of nanoparticle stability and abrupt heterointerfaces for a rich variety of growth scenarios. Therefore, our results provide a powerful tool for obtaining high quality InAs-InP nanowire heterostructures with well-controlled properties and can be extended to other material combinations based on the group V interchange.

  10. Disruption of perineuronal nets increases the frequency of sharp wave ripple events.

    Sun, Zhi Yong; Bozzelli, P Lorenzo; Caccavano, Adam; Allen, Megan; Balmuth, Jason; Vicini, Stefano; Wu, Jian-Young; Conant, Katherine

    2018-01-01

    Hippocampal sharp wave ripples (SWRs) represent irregularly occurring synchronous neuronal population events that are observed during phases of rest and slow wave sleep. SWR activity that follows learning involves sequential replay of training-associated neuronal assemblies and is critical for systems level memory consolidation. SWRs are initiated by CA2 or CA3 pyramidal cells (PCs) and require initial excitation of CA1 PCs as well as participation of parvalbumin (PV) expressing fast spiking (FS) inhibitory interneurons. These interneurons are relatively unique in that they represent the major neuronal cell type known to be surrounded by perineuronal nets (PNNs), lattice like structures composed of a hyaluronin backbone that surround the cell soma and proximal dendrites. Though the function of the PNN is not completely understood, previous studies suggest it may serve to localize glutamatergic input to synaptic contacts and thus influence the activity of ensheathed cells. Noting that FS PV interneurons impact the activity of PCs thought to initiate SWRs, and that their activity is critical to ripple expression, we examine the effects of PNN integrity on SWR activity in the hippocampus. Extracellular recordings from the stratum radiatum of horizontal murine hippocampal hemisections demonstrate SWRs that occur spontaneously in CA1. As compared with vehicle, pre-treatment (120 min) of paired hemislices with hyaluronidase, which cleaves the hyaluronin backbone of the PNN, decreases PNN integrity and increases SWR frequency. Pre-treatment with chondroitinase, which cleaves PNN side chains, also increases SWR frequency. Together, these data contribute to an emerging appreciation of extracellular matrix as a regulator of neuronal plasticity and suggest that one function of mature perineuronal nets could be to modulate the frequency of SWR events. © 2017 Wiley Periodicals, Inc.

  11. Myocardial contusion in patients with blunt chest trauma as evaluated by thallium 201 myocardial scintigraphy

    Bodin, L.; Rouby, J.J.; Viars, P.

    1988-01-01

    Fifty five patients suffering from blunt chest trauma were studied to assess the diagnosis of myocardial contusion using thallium 201 myocardial scintigraphy. Thirty-eight patients had consistent scintigraphic defects and were considered to have a myocardial contusion. All patients with scintigraphic defects had paroxysmal arrhythmias and/or ECG abnormalities. Of 38 patients, 32 had localized ST-T segment abnormalities; 29, ST-T segment abnormalities suggesting involvement of the same cardiac area as scintigraphic defects; 21, echocardiographic abnormalities. Sixteen patients had segmental hypokinesia involving the same cardiac area as the scintigraphic defects. Fifteen patients had clinical signs suggestive of myocardial contusion and scintigraphic defects. Almost 70 percent of patients with blunt chest trauma had scintigraphic defects related to areas of myocardial contusion. When thallium 201 myocardial scintigraphy directly showed myocardial lesion, two-dimensional echocardiography and standard ECG detected related functional consequences of cardiac trauma

  12. Clinical Characteristics and Outcomes of Patients with Myocardial Infarction, Myocardial Injury, and Nonelevated Troponins

    Sarkisian, Laura; Saaby, Lotte; Poulsen, Tina S

    2016-01-01

    BACKGROUND: Cardiac troponins have emerged as the preferred biomarkers for detecting myocardial necrosis and diagnosing myocardial infarction. However, current cardiac troponin assays do not discriminate between ischemic and nonischemic causes of myocardial cell death. Thus, when an increased...... troponin value is encountered in the absence of obvious myocardial ischemia, a careful search for other clinical conditions is crucial. METHODS: In 2010 to 2011, we prospectively studied hospitalized patients who had cardiac troponin I measured on clinical indication. An acute myocardial infarction...... was diagnosed in cases of a cardiac troponin I increase or decrease pattern with at least 1 value >30 ng/L (99th percentile) together with myocardial ischemia. Myocardial injury was defined as cardiac troponin I values >30 ng/L, but without signs or symptoms indicating overt cardiac ischemia. Patients with peak...

  13. Assessment of myocardial washout of Tc-99m-sestamibi in patients with chronic heart failure. Comparison with normal control

    Kumita, Shin-ichiro; Seino, Yoshihiko; Cho, Keiichi; Nakajo, Hidenobu; Toba, Masahiro; Fukushima, Yoshimitsu; Takano, Teruo; Kumazaki, Tatsuo [Nippon Medical School, Tokyo (Japan); Okamoto, Noriake [Bristol-Myers Squibb K.K., Tokyo (Japan)

    2002-06-01

    In contrast to {sup 201}TlCl, {sup 99m}Tc-sestamibi shows very slow myocardial clearance after its initial myocardial uptake. In the present study, myocardial washout of {sup 99m}Tc-sestamibi was calculated in patients with non-ischemic chronic heart failure (CHF) and compared with biventricular parameters obtained from first-pass and ECG-gated myocardial perfusion SPECT data. After administration of {sup 99m}Tc-sestamibi, 25 patients with CHF and 8 normal controls (NC) were examined by ECG-gated myocardial perfusion SPECT and planar data acquisition in the early and delayed (interval of 3 hours) phase. Left ventricular ejection fraction (LVEF, %), peak filling rate (PFR, sec{sup -1}), end-diastolic volume (LVEDV, ml) and end-systolic volume (LVESV, ml) were automatically calculated from the ECG-gated SPECT data. Myocardial washout rates over 3 hours were calculated from the early and delayed planar images. Myocardial washout rates in the CHF group (39.6{+-}5.2%) were significantly higher than those in the NC group (31.2{+-}5.5%, p<0.01). The myocardial washout rates for the 33 subjects showed significant correlations with LVEF (r=-0.61, p<0.001), PFR (r=-0.47, p<0.01), LVEDV (r=0.45, p<0.01) and LVESV (r=0.48, p<0.01). The myocardial washout rate of {sup 99m}Tc-sestamibi is considered to be a novel marker for the diagnosis of myocardial damage in patients with chronic heart failure. (author)

  14. Myocardial strains from 3D displacement encoded magnetic resonance imaging

    Kindberg, Katarina; Haraldsson, Henrik; Sigfridsson, Andreas; Engvall, Jan; Ingels, Neil B Jr; Ebbers, Tino; Karlsson, Matts

    2012-01-01

    The ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. The recent development of magnetic resonance imaging methods, such as harmonic phase analysis of tagging and displacement encoding with stimulated echoes (DENSE), make detailed non-invasive 3D kinematic analyses of human myocardium possible in the clinic and for research purposes. A robust analysis method is required, however. We propose to estimate strain using a polynomial function which produces local models of the displacement field obtained with DENSE. Given a specific polynomial order, the model is obtained as the least squares fit of the acquired displacement field. These local models are subsequently used to produce estimates of the full strain tensor. The proposed method is evaluated on a numerical phantom as well as in vivo on a healthy human heart. The evaluation showed that the proposed method produced accurate results and showed low sensitivity to noise in the numerical phantom. The method was also demonstrated in vivo by assessment of the full strain tensor and to resolve transmural strain variations. Strain estimation within a 3D myocardial volume based on polynomial functions yields accurate and robust results when validated on an analytical model. The polynomial field is capable of resolving the measured material positions from the in vivo data, and the obtained in vivo strains values agree with previously reported myocardial strains in normal human hearts

  15. Myocardial strains from 3D displacement encoded magnetic resonance imaging

    Kindberg Katarina

    2012-04-01

    Full Text Available Abstract Background The ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. The recent development of magnetic resonance imaging methods, such as harmonic phase analysis of tagging and displacement encoding with stimulated echoes (DENSE, make detailed non-invasive 3D kinematic analyses of human myocardium possible in the clinic and for research purposes. A robust analysis method is required, however. Methods We propose to estimate strain using a polynomial function which produces local models of the displacement field obtained with DENSE. Given a specific polynomial order, the model is obtained as the least squares fit of the acquired displacement field. These local models are subsequently used to produce estimates of the full strain tensor. Results The proposed method is evaluated on a numerical phantom as well as in vivo on a healthy human heart. The evaluation showed that the proposed method produced accurate results and showed low sensitivity to noise in the numerical phantom. The method was also demonstrated in vivo by assessment of the full strain tensor and to resolve transmural strain variations. Conclusions Strain estimation within a 3D myocardial volume based on polynomial functions yields accurate and robust results when validated on an analytical model. The polynomial field is capable of resolving the measured material positions from the in vivo data, and the obtained in vivo strains values agree with previously reported myocardial strains in normal human hearts.

  16. Nifedipine for angina and acute myocardial ischemia

    P.G. Hugenholtz (Paul); J.W. de Jong (Jan Willem); P.D. Verdouw (Pieter); P.W.J.C. Serruys (Patrick)

    1983-01-01

    textabstractThis paper reviews the mechanisms believed to be responsible for myocardial ischaemia and the mode of action of calcium antagonist drugs. The clinical management of patients with myocardial ischaemia is discussed in the context of current knowledge about patho-physiology and drug action.

  17. The end of the unique myocardial band

    MacIver, David H; Partridge, John B; Agger, Peter

    2018-01-01

    Two of the leading concepts of mural ventricular architecture are the unique myocardial band and the myocardial mesh model. We have described, in an accompanying article published in this journal, how the anatomical, histological and high-resolution computed tomographic studies strongly favour th...

  18. When is 201Tl myocardial scintigraphy indicated?

    Klepzig, H. Jr.; Kaltenbach, M.

    1987-01-01

    Myocardial scintigraphy with thallium-201 has met with good acceptance in cardiology and has proven its value. The method implies only low risk and yields diagnostic results that allow verification or disqualification of suspected myocardial ischemia in those cases where there is only reduced accuracy of the exercise electrocardiogram. (TRV) [de

  19. Do episodes of anger trigger myocardial infarction?

    Möller, J; Hallqvist, J; Diderichsen, Finn

    1999-01-01

    Our objectives were to study anger as a trigger of acute myocardial infarction (MI) and to explore potential effect modification by usual behavioral patterns related to hostility.......Our objectives were to study anger as a trigger of acute myocardial infarction (MI) and to explore potential effect modification by usual behavioral patterns related to hostility....

  20. Monitoring of myocardial edema following acute myocardial infarction

    Tahir, E.; Sinn, M.; Avanesov, M.; Wien, J.; Saering, D.; Stehning, C.; Radunski, U. K.; Muellerleile, K.; Adam, G.; Lund, G. K.

    2015-01-01

    Full text: Currently, myocardial edema monitoring after acute myocardial infarction (AMI) is based on visualization of the region with increased signal-intensity on T2-weighted images. Native T1 and T2 mapping are promising novel MRI techniques to quantitatively assess myocardial edema. The purpose of the study was to quantitatively evaluate resorption of myocardial edema following AMI by native T1 and T2 -mapping cardiac magnetic resonance imaging (CMR). CMR (1.5 Tesla Philips Achieva) was performed in 30 patients four times after reperfused AMI at baseline (BL) at 9±6 days after infarction and at 7±1 weeks (follow-up 1, FU1), 3.6±0.5 months (FU2) and 6.5±0.7 months (FU3), respectively. Edema sensitive black-blood T2-weighted (T2w) STIR CMR was performed on end-diastolic LV short-axes. A free-breathing, navigatorgated multi-echo sequence was used for short-axis T2 mapping. T1 mapping was performed using the modified look-locker inversion recovery (MOLLI) sequence. T2 maps were calculated from nine and T1 maps from eight echoes using a dedicated plug-in written for OsiriX software. Two experienced observers independently evaluated T2w-CMR as well as T1 and T2 mapping using the HeAT-Software applying a threshold method. Size of edema and prolongation of the native T1- or T2-time was measured using a cutoff >2SD of remote normal myocardium. Edema size continuously decreased from BL with 32.8 %LV to 24.6 %LV at FU1, to 19.1 %LV at FU2 and to 16.4 %LV at FU3 using T2w-CMR. An almost identical decrease of edema size was observed using native T1 and T2 - mapping. T2 times only decreased between BL from 79±5 ms to 73±2 ms at FU1 (P<0.05), but no further change was observed at later time points with 70±5 ms at FU2 and 70±6 ms at FU3. At all time points the T2 times of remote normal myocardium were about 50±2 ms and significantly lower compared to the edema zone. Also native T1 time within the edema was with 1253 ±103 ms significantly increased compared to remote

  1. Exploring Moho sharpness in Northeastern North China Craton with frequency-dependence analysis of Ps receiver function

    Zhang, P.; Yao, H.; Chen, L.; WANG, X.; Fang, L.

    2017-12-01

    The North China Craton (NCC), one of the oldest cratons in the world, has attracted wide attention in Earth Science for decades because of the unusual Mesozoic destruction of its cratonic lithosphere. Understanding the deep processes and mechanism of this craton destruction demands detailed knowledge about the deep structure of this region. In this study, we calculate P-wave receiver functions (RFs) with two-year teleseismic records from the North China Seismic Array ( 200 stations) deployed in the northeastern NCC. We observe both diffused and concentered PpPs signals from the Moho in RF waveforms, which indicates heterogeneous Moho sharpness variations in the study region. Synthetic Ps phases generated from broad positive velocity gradients at the depth of the Moho (referred as Pms) show a clear frequency dependence nature, which in turn is required to constrain the sharpness of the velocity gradient. Practically, characterizing such a frequency dependence feature in real data is challenging, because of low signal-to-noise ratio, contaminations by multiples generated from shallow structure, distorted signal stacking especially in double-peak Pms signals, etc. We attempt to address these issues by, firstly, utilizing a high-resolution Moho depth model of this region to predict theoretical delay times of Pms that facilitate more accurate Pms identifications. The Moho depth model is derived by wave-equation based poststack depth migration on both Ps phase and surface-reflected multiples in RFs in our previous study (Zhang et al., submitted to JGR). Second, we select data from a major back azimuth range of 100° - 220° that includes 70% teleseismic events due to the uneven data coverage and to avoid azimuthal influence as well. Finally, we apply an adaptive cross-correlation stacking of Pms signals in RFs for each station within different frequency bands. High-quality Pms signals at different frequencies will be selected after careful visual inspection and adaptive

  2. Ventricular and myocardial scintiscanning: Methodical fundamentals

    Standke, R.; Hoer, G.; Maul, F.D.

    1984-01-01

    Nuclear cardiology is concerned with non invasive procedures to quantitate global and regional left ventricular function (Radionuclide ventriculography), also the imaging of vitally perfused myocardium (Myocardial scintigraphy) is achieved. A gammacamera and a minicomputer are necessary. Radionuclide ventriculography enables the analysis of global and regional time dependent left ventricular volume curves and hence the evaluation of contraction and contractility of the heart muscle. The basis is a sequence of scans covering an average heartcycle. This sequence may be produced either by first pass or equilibrium technique. Myocardial scintigraphy at rest images vital myocardium, scans immediately after exercise represent the interference of myocardial perfusion and muscle mass. The regional difference (Redistribution) between normalized exercise- and rest scans provide quantitative parameters to detect impairment of exercise-induced myocardial perfusion anomalies. The procedures of sectorial analysis of left ventricular function and myocardial perfusion are presented. (orig.) [de

  3. Anticoagulants for secondary prevention after acute myocardial infarction: lessons from the past decade

    Atar, D.; Bode, C.; Stuerzenbecher, A.; Verheugt, F.W.A.

    2014-01-01

    The impact of an acute coronary syndrome (ACS) event, such as an acute myocardial infarction (MI), is not limited to the acute management phase; patients face an elevated risk of residual atherothrombotic events that commonly requires chronic management for months or even years. Significant advances

  4. SHARP: A multi-mission artificial intelligence system for spacecraft telemetry monitoring and diagnosis

    Lawson, Denise L.; James, Mark L.

    1989-01-01

    The Spacecraft Health Automated Reasoning Prototype (SHARP) is a system designed to demonstrate automated health and status analysis for multi-mission spacecraft and ground data systems operations. Telecommunications link analysis of the Voyager 2 spacecraft is the initial focus for the SHARP system demonstration which will occur during Voyager's encounter with the planet Neptune in August, 1989, in parallel with real time Voyager operations. The SHARP system combines conventional computer science methodologies with artificial intelligence techniques to produce an effective method for detecting and analyzing potential spacecraft and ground systems problems. The system performs real time analysis of spacecraft and other related telemetry, and is also capable of examining data in historical context. A brief introduction is given to the spacecraft and ground systems monitoring process at the Jet Propulsion Laboratory. The current method of operation for monitoring the Voyager Telecommunications subsystem is described, and the difficulties associated with the existing technology are highlighted. The approach taken in the SHARP system to overcome the current limitations is also described, as well as both the conventional and artificial intelligence solutions developed in SHARP.

  5. SHARP: A multi-mission AI system for spacecraft telemetry monitoring and diagnosis

    Lawson, Denise L.; James, Mark L.

    1989-01-01

    The Spacecraft Health Automated Reasoning Prototype (SHARP) is a system designed to demonstrate automated health and status analysis for multi-mission spacecraft and ground data systems operations. Telecommunications link analysis of the Voyager II spacecraft is the initial focus for the SHARP system demonstration which will occur during Voyager's encounter with the planet Neptune in August, 1989, in parallel with real-time Voyager operations. The SHARP system combines conventional computer science methodologies with artificial intelligence techniques to produce an effective method for detecting and analyzing potential spacecraft and ground systems problems. The system performs real-time analysis of spacecraft and other related telemetry, and is also capable of examining data in historical context. A brief introduction is given to the spacecraft and ground systems monitoring process at the Jet Propulsion Laboratory. The current method of operation for monitoring the Voyager Telecommunications subsystem is described, and the difficulties associated with the existing technology are highlighted. The approach taken in the SHARP system to overcome the current limitations is also described, as well as both the conventional and artificial intelligence solutions developed in SHARP.

  6. Consideration of vision and picture quality: psychological effects induced by picture sharpness

    Kusaka, Hideo

    1989-08-01

    A psychological hierarchy model of human vision(1)(2) suggests that the visual signals are processed in a serial manner from lower to higher stages: that is "sensation" - "perception" - "emotion." For designing a future television system, it is important to find out what kinds of physical factors affect the "emotion" experienced by an observer in front of the display. This paper describes the psychological effects induced by the sharpness of the picture. The subjective picture quality was evaluated for the same pictures with five different levels of sharpness. The experiment was performed on two kinds of printed pictures: (A) a woman's face, and (B) a town corner. From these experiments, it was found that the amount of high-frequency peaking (physical value of the sharpness) which psychologically gives the best picture quality, differs between pictures (A) and (B). That is, the optimum picture sharpness differs depending on the picture content. From these results, we have concluded that the psychophysical sharpness of the picture is not only determined at the stage of "perception" (e.g., resolution or signal to noise ratio, which everyone can judge immediately), but also at the stage of "emotion" (e.g., sensation of reality or beauty).

  7. Weapon Use in Korean Homicide: Differences Between Homicides Involving Sharp and Blunt Instruments.

    Park, Jisun; Son, Hyeonseo

    2017-10-23

    On the basis of information regarding 276 homicides committed in South Korea between 1987 and 2008, we compared offenders' and victims' characteristics, injury locations, weapon-related behavior, and offending behavior between homicides involving sharp and blunt instruments. The victims of sharp-force homicide were much younger relative to those of blunt-force homicide. In addition, homicides involving blunt instruments were more likely to be committed by offenders who lived with the victims. Most sharp-force homicides involved injuries to the torso, while blunt-force homicides involved mainly head injuries. Furthermore, perpetrators of sharp-force homicides tended to preselect their weapons, while those of blunt-force homicides were likely to use weapons of opportunity. Logistic regression analysis identified a number of factors, including injury location and body transportation, which significantly predicted weapon type. As this was the first South Korean study to compare sharp- and blunt-force homicides, the results have practical implications for homicide investigations. © 2017 American Academy of Forensic Sciences.

  8. Objective assessment of knife sharpness over a working day cutting meat.

    Savescu, Adriana; Cuny-Guerrier, Aude; Wild, Pascal; Reno, Gilles; Aublet-Cuvelier, Agnès; Claudon, Laurent

    2018-04-01

    Knife sharpness is one of multiple factors involved in musculoskeletal disorders in industrial meat cutting. The aim of this study was to objectively evaluate, in real working situations, how knife sharpness changed over a working day cutting meat, and to analyse the impact of sharpening, steeling and meat-cutting activities on these variations. Twenty-two meat-cutting workers from three different companies participated in the study. The methods included measurements of knife sharpness in relation to real work situations and consideration of the way meat-cutting and sharpening operations were organised. Results showed that the type of meat-cutting activities, the steeling strategy adopted by the worker, including the types of tool used, and the overall organisation of the sharpening task all had a significant influence on how knife sharpness evolved over a 2-h period and over an entire working day. To improve MSD prevention, sharpening and steeling operations should not be considered as independent activities, but taken into account as a continuity of working actions. Appropriate assessment of knife sharpness by meat cutters affects how they organise meat-cutting and sharpening tasks. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Direct Evidence that Myocardial Insulin Resistance following Myocardial Ischemia Contributes to Post-Ischemic Heart Failure

    Fu, Feng; Zhao, Kun; Li, Jia; Xu, Jie; Zhang, Yuan; Liu, Chengfeng; Yang, Weidong; Gao, Chao; Li, Jun; Zhang, Haifeng; Li, Yan; Cui, Qin; Wang, Haichang; Tao, Ling; Wang, Jing; Quon, Michael J; Gao, Feng

    2015-01-01

    A close link between heart failure (HF) and systemic insulin resistance has been well documented, whereas myocardial insulin resistance and its association with HF are inadequately investigated. This study aims to determine the role of myocardial insulin resistance in ischemic HF and its underlying mechanisms. Male Sprague-Dawley rats subjected to myocardial infarction (MI) developed progressive left ventricular dilation with dysfunction and HF at 4 wk post-MI. Of note, myocardial insulin sensitivity was decreased as early as 1 wk after MI, which was accompanied by increased production of myocardial TNF-α. Overexpression of TNF-α in heart mimicked impaired insulin signaling and cardiac dysfunction leading to HF observed after MI. Treatment of rats with a specific TNF-α inhibitor improved myocardial insulin signaling post-MI. Insulin treatment given immediately following MI suppressed myocardial TNF-α production and improved cardiac insulin sensitivity and opposed cardiac dysfunction/remodeling. Moreover, tamoxifen-induced cardiomyocyte-specific insulin receptor knockout mice exhibited aggravated post-ischemic ventricular remodeling and dysfunction compared with controls. In conclusion, MI induces myocardial insulin resistance (without systemic insulin resistance) mediated partly by ischemia-induced myocardial TNF-α overproduction and promotes the development of HF. Our findings underscore the direct and essential role of myocardial insulin signaling in protection against post-ischemic HF. PMID:26659007

  10. Three-dimension structure of ventricular myocardial fibers after myocardial infarction

    Li Libin

    2010-11-01

    Full Text Available Abstract Background To explore the pathological changes of three-dimension structure of ventricular myocardial fibers after anterior myocardial infarction in dog heart. Methods Fourteen acute anterior myocardial infarction models were made from healthy dogs (mean weight 17.6 ± 2.5 kg. Six out of 14 dogs with old myocardial infarction were sacrificed, and their hearts were harvested after they survived the acute anterior myocardial infarction for 3 months. Each heart was dissected into ventricular myocardial band (VMB, morphological characters in infarction region were observed, and infarct size percents in descending segment and ascending segment were calculated. Results Six dog hearts were successfully dissected into VMB. Uncorresponding damages in myocardial fibers of descending segment and ascending segment were found in apical circle in anterior wall infarction. Infarct size percent in the ascending segment was significantly larger than that in the descending segment (23.36 ± 3.15 (SD vs 30.69 ± 2.40%, P = 0.0033; the long axis of infarction area was perpendicular to the orientation of myocardial fibers in ascending segment; however, the long axis of the infarction area was parallel with the orientation of myocardial fibers in descending segment. Conclusions We found that damages were different in both morphology and size in ascending segment and descending segment in heart with myocardial infarction. This may provide an important insight for us to understand the mechanism of heart failure following coronary artery diseases.

  11. Diagnostic value of exercise induced 18F-FDG myocardial metabolism scintigraphy in myocardial ischemia

    Shen Rui; He Zuoxiang; Shi Rongfang; Liu Xiujie; Tian Yueqin; Guo Feng; Wei Hongxing; Wu Yongjian; Qin Xuewen; Gao Runlin

    2006-01-01

    Objective: To evaluate the feasibility and diagnostic accuracy of exercise induced myocardial imaging with 18 F-fluorodeoxyglucose (FDG) in myocardial ischemia. Methods: Twenty-six patients with known or suspected coronary artery, disease (CAD) and with no prior myocardial infarction underwent simultaneous myocardial perfusion and metabolism imaging following intravenous injection of 99 Tc m -methoxy-isobutylisonitrile ( 99 Tc m -sestamibi) and 18 F-FDG at peak exercise. Subsequently rest perfusion imaging and coronary angiography (CAG) were performed in all patients. Exercise 18 F-FDG myocardial imaging was compared with 99 Tc m -sestamibi imaging and CAG. Results: In 22 patients with ≥50% narrowing over l coronary artery, 18 had perfusion abnormalities (sensitivity 82%), whereas 20 had abnormal myocardial 18 F-FDG uptake (sensitivity 91%, P>0.05). Patients with reversible (12 cases) or partial reversible (3 cases) perfusion abnormalities had increased myocardial 18 F-FDG uptake in abnormal perfusion segments. Compared with CAG, perfusion defect was seen in myocardial segments corresponding to 25 vascular territories of 51 vessels with ≥50% narrowing in 22 patients in 99 Tc m -sestamibi imaging (sensitivity 49%), whereas increased 18 F-FDG uptake was seen in 34 vascular territories (sensitivity 67%, P=0.008). Conclusions: Exercise induced myocardial ischemia can be imaged directly with 18 F-FDG. Combined exercise 18 F-FDG and 99 Tc m -sestamibi imaging provides a better assessment of exercise-induced myocardial ischemia as compared with exercise-rest perfusion imaging. (authors)

  12. Summer High School Apprenticeship Research Program (SHARP) of the National Aeronautics and Space Administration

    1984-01-01

    A total of 125 talented high school students had the opportunity to gain first hand experience about science and engineering careers by working directly with a NASA scientist or engineer during the summer. This marked the fifth year of operation for NASA's Summer High School Apprenticehsip Research Program (SHARP). Ferguson Bryan served as the SHARP contractor and worked closely with NASA staff at Headquarters and the eight participating sites to plan, implement, and evaluate the Program. The main objectives were to strengthen SHARP and expand the number of students in the Program. These eight sites participated in the Program: Ames Research Center North, Ames' Dryden Flight Research Facility, Goddard Space Flight Center, Goddard's Wallops Flight Facility, Kennedy Space Center, Langley Research Center, Lewis Research Center, and Marshall Space Flight Center.

  13. Enhanced Transmissions Through Three-dimensional Cascade Sharp Waveguide Bends Using C-slit Diaphragms.

    Yang, Rui; Hu, Bowei; Zhang, Aofang; Gao, Dongxing; Wang, Hui; Shi, Ayuan; Lei, Zhenya; Yang, Pei

    2017-03-21

    Transmission properties through sharp rectangular waveguide bends are investigated to determine the cut-off bending angles of the wave propagation. We show that a simple metallic diaphragm at the bending corner with properly devised sub-wavelength defect apertures of C-slits would be readily to turn on the transmissions with scarce reflections of the propagating modes, while preserving the integrity of the transmitting fields soon after the bends. In particularly, our design also demonstrates the capability of eliminating all the unwanted cavity resonant transmissions that exist in the three-dimensional cascade sharp waveguide bends, and solely let the desired signals travel along the whole passage of the waveguide. The present approach, using C-slit diaphragms to support the sharp bending behaviors of the guided waves with greatly enhanced transmissions, would be especially effective in constructing novel waveguides and pave the way for the development of more compact and miniaturized electromagnetic systems that exploit these waveguide bends.

  14. Lacosamide and Levetiracetam Have No Effect on Sharp-Wave Ripple Rate.

    Kudlacek, Jan; Chvojka, Jan; Posusta, Antonin; Kovacova, Lubica; Hong, Seung Bong; Weiss, Shennan; Volna, Kamila; Marusic, Petr; Otahal, Jakub; Jiruska, Premysl

    2017-01-01

    Pathological high-frequency oscillations are a novel marker used to improve the delineation of epileptogenic tissue and, hence, the outcome of epilepsy surgery. Their practical clinical utilization is curtailed by the inability to discriminate them from physiological oscillations due to frequency overlap. Although it is well documented that pathological HFOs are suppressed by antiepileptic drugs (AEDs), the effect of AEDs on normal HFOs is not well known. In this experimental study, we have explored whether physiological HFOs (sharp-wave ripples) of hippocampal origin respond to AED treatment. The results show that application of a single dose of levetiracetam or lacosamide does not reduce the rate of sharp-wave ripples. In addition, it seems that these new generation drugs do not negatively affect the cellular and network mechanisms involved in sharp-wave ripple generation, which may provide a plausible explanation for the absence of significant negative effects on cognitive functions of these drugs, particularly on memory.

  15. Relationship between sharps disposal containers and Clostridium difficile infections in acute care hospitals.

    Pogorzelska-Maziarz, Monika

    2015-10-01

    Sharps disposal containers are ubiquitous in health care facilities; however, there is paucity of data on their potential role in pathogen transmission. This study assessed the relationship between use of single-use versus reusable sharps containers and rates of Clostridium difficile infections in a national sample of hospitals. A 2013 survey of 1,990 hospitals collected data on the use of sharps containers. Responses were linked to the 2012 Medicare Provider Analysis and Review dataset. Bivariate and multivariable negative binomial regression were conducted to examine differences in C difficile rates between hospitals using single-use versus reusable containers. There were 604 hospitals who completed the survey; of these, 539 provided data on use of sharps containers in 2012 (27% response rate). Hospitals had, on average, 289 beds (SD ± 203) and were predominantly non-for-profit (67%) and nonteaching (63%). Most used reusable sharps containers (72%). In bivariate regression, hospitals using single-use containers had significantly lower rates of C difficile versus hospitals using reusable containers (incidence rate ratio [IRR] = 0.846, P = .001). This relationship persisted in multivariable regression (IRR = 0.870, P = .003) after controlling for other hospital characteristics. This is the first study to show a link between use of single-use sharps containers and lower C difficile rates. Future research should investigate the potential for environmental contamination of reusable containers and the role they may play in pathogen transmission. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  16. Myocardial perfusion imaging with dual energy CT

    Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, SMG-SNU Boramae Medical Center, Seoul (Korea, Republic of); De Cecco, Carlo N. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncology and Pathology, University of Rome “Sapienza”, Rome (Italy); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Spandorfer, Adam; Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States)

    2016-10-15

    Highlights: • Stress dual-energy sCTMPI offers the possibility to directly detect the presence of myocardial perfusion defects. • Stress dual-energy sCTMPI allows differentiating between reversible and fixed myocardial perfusion defects. • The combination of coronary CT angiography and dual-energy sCTMPI can improve the ability of CT to detect hemodynamically relevant coronary artery disease. - Abstract: Dual-energy CT (DECT) enables simultaneous use of two different tube voltages, thus different x-ray absorption characteristics are acquired in the same anatomic location with two different X-ray spectra. The various DECT techniques allow material decomposition and mapping of the iodine distribution within the myocardium. Static dual-energy myocardial perfusion imaging (sCTMPI) using pharmacological stress agents demonstrate myocardial ischemia by single snapshot images of myocardial iodine distribution. sCTMPI gives incremental values to coronary artery stenosis detected on coronary CT angiography (CCTA) by showing consequent reversible or fixed myocardial perfusion defects. The comprehensive acquisition of CCTA and sCTMPI offers extensive morphological and functional evaluation of coronary artery disease. Recent studies have revealed that dual-energy sCTMPI shows promising diagnostic accuracy for the detection of hemodynamically significant coronary artery disease compared to single-photon emission computed tomography, invasive coronary angiography, and cardiac MRI. The aim of this review is to present currently available DECT techniques for static myocardial perfusion imaging and recent clinical applications and ongoing investigations.

  17. Inference for the Sharpe Ratio Using a Likelihood-Based Approach

    Ying Liu

    2012-01-01

    Full Text Available The Sharpe ratio is the prominent risk-adjusted performance measure used by practitioners. Statistical testing of this ratio using its asymptotic distribution has lagged behind its use. In this paper, highly accurate likelihood analysis is applied for inference on the Sharpe ratio. Both the one- and two-sample problems are considered. The methodology has O(n−3/2 distributional accuracy and can be implemented using any parametric return distribution structure. Simulations are provided to demonstrate the method's superior accuracy over existing methods used for testing in the literature.

  18. A rare case of a sharp foreign body on the vocal cord

    Khairunnisak Misron

    2017-08-01

    Full Text Available A foreign body (FB in the upper aerodigestive tract is a common clinical problem that presents as as acute emergency. Sharp FB, such as fish bone or chicken bone, commonly lodges in the tonsil, base of tongue, vallecula or pyriform fossa. Dislodgement of a FB into the laryngopharynx is very rare and specifically onto the vocal cord is extremely uncommon. This case report illustrates a rare case of a sharp FB that was dislodged into the airway and stuck on to the right vocal cord, which was removed under local anaesthesia.

  19. Comparison of image sharpness metrics and real-time sharpening methods with GPU implementations

    De Villiers, Johan P

    2010-06-01

    Full Text Available , and not in trying to adjust the image to some fixed sharpness value. With the advent of the increased progammability of Graphics Pro- cessing Units (GPU) and their seemingly ever increasing number of processor cores (the dual-GPU NVidia GTX295 has 480 cores...) Quadro MDS 140M 16 400 64 700 ATI HD 2400XT 40 800 64 700 NVidia 9600GT 64 650 256 900 NVidia GTX280 240 602 512 1107 2 Metric descriptions Three metrics are used to evaluate images for sharpness. The first two are a measure of how much information...

  20. Soft yet Sharp Interfaces in a Vertex Model of Confluent Tissue

    Sussman, Daniel M.; Schwarz, J. M.; Marchetti, M. Cristina; Manning, M. Lisa

    2018-01-01

    How can dense biological tissue maintain sharp boundaries between coexisting cell populations? We explore this question within a simple vertex model for cells, focusing on the role of topology and tissue surface tension. We show that the ability of cells to independently regulate adhesivity and tension, together with neighbor-based interaction rules, lets them support strikingly unusual interfaces. In particular, we show that mechanical- and fluctuation-based measurements of the effective surface tension of a cellular aggregate yield different results, leading to mechanically soft interfaces that are nevertheless extremely sharp.

  1. Epitaxial growth of topological insulator Bi{sub 2}Se{sub 3} film on Si(111) with atomically sharp interface

    Bansal, Namrata [Department of Electrical and Computer Engineering, Rutgers, State University of New Jersey, Piscataway, NJ 08854 (United States); Kim, Yong Seung [Graphene Research Institute, Sejong University, Seoul 143-747 (Korea, Republic of); Edrey, Eliav; Brahlek, Matthew; Horibe, Yoichi [Department of Physics and Astronomy, Rutgers, State University of New Jersey, Piscataway, NJ 08854 (United States); Iida, Keiko; Tanimura, Makoto [Research Department, Nissan Arc, Ltd. Yokosuka, Kanagawa 237-0061 (Japan); Li Guohong; Feng Tian; Lee, Hang-Dong; Gustafsson, Torgny; Andrei, Eva [Department of Physics and Astronomy, Rutgers, State University of New Jersey, Piscataway, NJ 08854 (United States); Oh, Seongshik, E-mail: ohsean@physics.rutgers.edu [Department of Physics and Astronomy, Rutgers, the State University of New Jersey, Piscataway, NJ 08854 (United States)

    2011-10-31

    Atomically sharp epitaxial growth of Bi{sub 2}Se{sub 3} films is achieved on Si(111) substrate with molecular beam epitaxy. Two-step growth process is found to be a key to achieve interfacial-layer-free epitaxial Bi{sub 2}Se{sub 3} films on Si substrates. With a single-step high temperature growth, second phase clusters are formed at an early stage. On the other hand, with low temperature growth, the film tends to be disordered even in the absence of a second phase. With a low temperature initial growth followed by a high temperature growth, second-phase-free atomically sharp interface is obtained between Bi{sub 2}Se{sub 3} and Si substrate, as verified by reflection high energy electron diffraction (RHEED), transmission electron microscopy (TEM) and X-ray diffraction. The lattice constant of Bi{sub 2}Se{sub 3} is observed to relax to its bulk value during the first quintuple layer according to RHEED analysis, implying the absence of strain from the substrate. TEM shows a fully epitaxial structure of Bi{sub 2}Se{sub 3} film down to the first quintuple layer without any second phase or an amorphous layer.

  2. Regional myocardial metabolism in patients with acute myocardial infarction assessed by positron emission tomography

    Schwaiger, M.; Brunken, R.; Grover-McKay, M.; Krivokapich, J.; Child, J.; Tillisch, J.H.; Phelps, M.E.; Schelbert, H.R.

    1986-01-01

    Positron emission tomography has been shown to distinguish between reversible and irreversible ischemic tissue injury. Using this technique, 13 patients with acute myocardial infarction were studied within 72 hours of onset of symptoms to evaluate regional blood flow and glucose metabolism with nitrogen (N)-13 ammonia and fluorine (F)-18 deoxyglucose, respectively. Serial noninvasive assessment of wall motion was performed to determine the prognostic value of metabolic indexes for functional tissue recovery. Segmental blood flow and glucose utilization were evaluated using a circumferential profile technique and compared with previously established semiquantitative criteria. Relative N-13 ammonia uptake was depressed in 32 left ventricular segments. Sixteen segments demonstrated a concordant decrease in flow and glucose metabolism. Regional function did not change over time in these segments. In contrast, 16 other segments with reduced blood flow revealed maintained F-18 deoxyglucose uptake consistent with remaining viable tissue. The average wall motion score improved significantly in these segments (p less than 0.01), yet the degree of recovery varied considerably among patients. Coronary anatomy was defined in 9 of 13 patients: patent infarct vessels supplied 8 of 10 segments with F-18 deoxyglucose uptake, while 10 of 13 segments in the territory of an occluded vessel showed concordant decreases in flow and metabolism (p less than 0.01). Thus, positron emission tomography reveals a high incidence of residual tissue viability in ventricular segments with reduced flow and impaired function during the subacute phase of myocardial infarction. Absence of residual tissue metabolism is associated with irreversible injury, while preservation of metabolic activity identifies segments with a variable outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Nitrogen-13-labeled ammonia for myocardial imaging

    Walsh, W.F.; Fill, H.R.; Harper, P.V.

    1977-01-01

    Cyclotron-produced nitrogen-13 (half-life 10 min), as labeled ammonia (/sup 13/NH/sub 4//sup +/), has been evaluated as a myocardial perfusion imaging agent. The regional myocardial uptake of /sup 13/NH/sub 4//sup +/ has been shown to be proportional to regional tissue perfusion in animal studies. Intravenously administered /sup 13/NH/sub 4//sup +/ is rapidly cleared from the circulation, being extracted by the liver (15 percent), lungs, myocardium (2 percent--4 percent), brain, kidney, and bladder. Myocardial ammonia is metabolized mainly to glutamine via the glutamine synthetase pathway. Pulmonary uptake is substantial, but usually transient, except in smokers where clearance may be delayed. The positron annihilation irradiation (511 keV) of /sup 13/N may be imaged with a scintillation camera, using either a specially designed tungsten collimator or a pinhole collimator. After early technical problems with collimation and the production method of /sup 13/NH/sub 4//sup +/ were overcome, reproducible high quality myocardial images were consistently obtained. The normal myocardial image was established to be of a homogeneous ''doughnut'' configuration. Imaging studies performed in patients with varying manifestations of ischemic and valvular heart disease showed a high incidence of localized perfusion defects, especially in patients with acute myocardial infarction. Sequential studies at short intervals in patients with acute infarction showed correlation between alterations in regional perfusion and the clinical course of the patient. It is concluded that myocardial imaging with /sup 13/NH/sub 4//sup +/ and a scintillation camera provides a valid and noninvasive means of assessing regional myocardial perfusion. This method is especially suitable for sequential studies of acute cardiac patients at short intervals. Coincidence imaging of the 511 keV annihilation irradiation provides a tomographic and potentially quantitative assessment of the

  4. Re-initiating professional working activity after myocardial infarction in primary percutaneous coronary intervention networks era

    Zdravko Babić

    2015-12-01

    Full Text Available Objectives: To investigate the aspects of return to work, socio-economic and quality of life aspects in 145 employed patients under 60 years of age treated with primary percutaneous coronary intervention for acute ST-elevation myocardial infarction. Material and Methods: During hospital treatment demographic and clinical data was collected. Data about major adverse cardiovascular events, rehabilitation, sick leave, discharge from job and retirement, salary, major life events and estimation of quality of life after myocardial infarction were obtained after follow-up (mean: 836±242 days. Results: Average sick leave was 126±125 days. Following myocardial infarction, 3.4% of patients were discharged from their jobs while 31.7% retired. Lower salary was reported in 17.9% patients, major life events in 9.7%, while 40.7% estimated quality of life as worse following the event. Longer hospitalization was reported in patients transferred from surrounding counties, those with inferior myocardial wall and right coronary artery affected. Age, hyperlipoproteinemia and lower education degree were connected to permanent working cessation. Significant salary decrease was observed in male patients. Employer type was related to sick leave duration. Impaired quality of life was observed in patients who underwent in-hospital rehabilitation and those from surrounding counties. Longer sick leave was observed in patients with lower income before and after myocardial infarction. These patients reported lower quality of life after myocardial infarction. Conclusions: Inadequate health policy and delayed cardiac rehabilitation after myocardial infarction may lead to prolonged hospitalization and sick leave as well as lower quality of life after the event, regardless of optimal treatment in acute phase of disease.

  5. Re-initiating professional working activity after myocardial infarction in primary percutaneous coronary intervention networks era.

    Babić, Zdravko; Pavlov, Marin; Oštrić, Mirjana; Milošević, Milan; Misigoj Duraković, Marjeta; Pintarić, Hrvoje

    2015-01-01

    To investigate the aspects of return to work, socio-economic and quality of life aspects in 145 employed patients under 60 years of age treated with primary percutaneous coronary intervention for acute ST-elevation myocardial infarction. During hospital treatment demographic and clinical data was collected. Data about major adverse cardiovascular events, rehabilitation, sick leave, discharge from job and retirement, salary, major life events and estimation of quality of life after myocardial infarction were obtained after follow-up (mean: 836±242 days). Average sick leave was 126±125 days. Following myocardial infarction, 3.4% of patients were discharged from their jobs while 31.7% retired. Lower salary was reported in 17.9% patients, major life events in 9.7%, while 40.7% estimated quality of life as worse following the event. Longer hospitalization was reported in patients transferred from surrounding counties, those with inferior myocardial wall and right coronary artery affected. Age, hyperlipoproteinemia and lower education degree were connected to permanent working cessation. Significant salary decrease was observed in male patients. Employer type was related to sick leave duration. Impaired quality of life was observed in patients who underwent in-hospital rehabilitation and those from surrounding counties. Longer sick leave was observed in patients with lower income before and after myocardial infarction. These patients reported lower quality of life after myocardial infarction. Inadequate health policy and delayed cardiac rehabilitation after myocardial infarction may lead to prolonged hospitalization and sick leave as well as lower quality of life after the event, regardless of optimal treatment in acute phase of disease. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  6. Myocardial infarction, androgen and the skin.

    Halim, M M; Meyrick, G; Jeans, W D; Murphy, D; Burton, J L

    1978-01-01

    Various indices of masculinity were compared in 48 men who had recovered from myocardial infarction and in their age-matched controls. We found little evidence to support the idea that myocardial infarction is related to increased androgenic stimulation. The patients with myocardial infarction had no increase in plasma testosterone, muscle thickness, sebum excretion rate, maximal sweat secretion rate, male pattern alopecia or density of terminal body hair, but as a group they had a slight increase in skin and bone thickness compared with the controls.

  7. [Hypertrophic cardiomyopathy showing no 123I-BMIPP myocardial accumulation with type I CD36 deficiency].

    Watanabe, K; Miyajima, S; Kusano, Y; Tanabe, N; Hirokawa, Y

    1997-07-01

    A 57 years old male consulted our hospital in complaining chest oppression and short of breath. Familial and dilated phase hypertrophic cardiomyopathy (HCM) was detected by ECG, echocardiography, left ventriculography and left ventricular endomyocardial biopsy. 201T1 SPECT showed regional increased accumulation in the ventricular septum, however, no myocardial accumulation of 123I-beta-methyl-p-iodophenylpentadecanoic acid (123I-BMIPP) was observed. We analyzed CD36 in this patient, and found he had type 1 CD36 deficiency. Myocardial uptake of long-chain fatty acids occurs via a specific transporter, which is homologous with human CD36. We hypothesize that CD36 deficiency, especially type 1 CD36 deficiency, might be one factor of no myocardial 123I-BMIPP uptake.

  8. Origins of sharp cosmic-ray electron structures and the DAMPE excess

    Huang, Xian-Jun; Wu, Yue-Liang; Zhang, Wei-Hong; Zhou, Yu-Feng

    2018-05-01

    Nearby sources may contribute to cosmic-ray electron (CRE) structures at high energies. Recently, the first DAMPE results on the CRE flux hinted at a narrow excess at energy ˜1.4 TeV . We show that in general a spectral structure with a narrow width appears in two scenarios. The first is spectrum broadening for the continuous sources with a δ -function-like injection spectrum. In this scenario, a finite width can develop after propagation through the Galaxy, which can reveal the distance of the source. Well-motivated sources include minispikes and subhalos formed by dark matter (DM) particles χs which annihilate directly into e+e- pairs. The second is phase-space shrinking for burstlike sources with a power-law-like injection spectrum. The spectrum after propagation can shrink at a cooling-related cutoff energy and form a sharp spectral peak. The peak can be more prominent due to the energy-dependent diffusion. In this scenario, the width of the excess constrains both the power index and the distance of the source. Possible such sources are pulsar wind nebulae (PWNe) and supernova remnants (SNRs). We analysis the DAMPE excess and find that the continuous DM sources should be fairly close within ˜0.3 kpc , and the annihilation cross sections are close to the thermal value. For the burstlike source, the narrow width of the excess suggests that the injection spectrum must be hard with power index significantly less than two, the distance is within ˜(3 - 4 ) kpc , and the age of the source is ˜0.16 Myr . In both scenarios, large anisotropies in the CRE flux are predicted. We identify possible candidates of minispike and PWN sources in the current Fermi-LAT 3FGL and ATNF catalog, respectively. The diffuse γ -rays from these sources can be well below the Galactic diffuse γ -ray backgrounds and less constrained by the Fermi-LAT data, if they are located at the low Galactic latitude regions.

  9. SPECT Myocardial Blood Flow Quantitation Concludes Equivocal Myocardial Perfusion SPECT Studies to Increase Diagnostic Benefits.

    Chen, Lung-Ching; Lin, Chih-Yuan; Chen, Ing-Jou; Ku, Chi-Tai; Chen, Yen-Kung; Hsu, Bailing

    2016-01-01

    Recently, myocardial blood flow quantitation with dynamic SPECT/CT has been reported to enhance the detection of coronary artery disease in human. This advance has created important clinical applications to coronary artery disease diagnosis and management for areas where myocardial perfusion PET tracers are not available. We present 2 clinical cases that undergone a combined test of 1-day rest/dipyridamole-stress dynamic SPECT and ECG-gated myocardial perfusion SPECT scans using an integrated imaging protocol and demonstrate that flow parameters are capable to conclude equivocal myocardial perfusion SPECT studies, therefore increasing diagnostic benefits to add value in making clinical decisions.

  10. Myocardial accumulation of a dopamine D[sub 2] receptor-binding radioligand, 2'-iodospiperone

    Saji, Hideo; Yonekura, Yoshiharu; Tanahashi, Kiyoko; Iida, Yasuhiko; Iwasaki, Yasushi; Magata, Yasuhiro; Konishi, Junji; Yokoyama, Akira [Kyoto Univ. (Japan). Faculty of Medicine

    1993-08-01

    [sup 125]I-iodospiperone (2'-ISP), which has a high and selective affinity for dopamine D[sub 2] receptors, produced a high myocardial accumulation of radioactivity in the early phase after intravenous injection into mice. A human scintigraphic study also showed that the myocardium was clearly visualized soon after intravenous injection of the tracer. Analysis of the myocardial homogenate obtained from mice showed that [sup 125]I-2'-ISP was metabolically stable and was taken up by the myocardium in its intact form. Administration of spiperone significantly reduced the myocardial uptake of [sup 125]I-2'-ISP in mice. Treatment with haloperidol and (+) butaclamol, which have a high affinity for dopamine D[sub 2] receptors, also tended to reduce the myocardial uptake of radioactivity, while (-)-butaclamol, which has no affinity for dopamine D[sub 2] receptors, caused no change in uptake. These findings suggest that the myocardial accumulation of 2'-ISP occurred in association with dopamine D[sub 2] (DA[sub 2]) receptors. (author).

  11. Multislice coronary computed tomographic angiography in emergency department presentations of unsuspected acute myocardial infarction.

    Hecht, Harvey S; Bhatti, Tandeep

    2009-01-01

    Coronary computed tomographic angiography (CCTA) is not indicated in the setting of acute myocardial infarction in the emergency department (ED). Nonetheless, acute coronary syndromes may have atypical presentations, and CCTA may be inadvertently performed in this setting. This study was designed to determine the frequency and characteristics of CCTA imaging of unsuspected acute myocardial infarction in the ED. All CCTAs performed in the ED at Lenox Hill Hospital were reviewed for clinical indications and subsequent course; patients with documented acute myocardial infarction were identified. Of the 500 CCTAs performed on ED patients in the Lenox Hill laboratory, 5 patients (1%) were imaged during the initial phase of an unsuspected acute myocardial infarction; in all cases the CCTAs were key to the diagnosis. The imaging characteristics were (1) total or subtotal occlusion and (2) transmural hypodensity in the infarct area. Although acute myocardial infarction on CCTA in ED patients is an infrequent event, proper and prompt recognition is critical for appropriate patient care, particularly as applications to the ED increase.

  12. Computer simulation of radiographic images sharpness in several system of image record

    Silva, Marcia Aparecida; Schiable, Homero; Frere, Annie France; Marques, Paulo M.A.; Oliveira, Henrique J.Q. de; Alves, Fatima F.R.; Medeiros, Regina B.

    1996-01-01

    A method to predict the influence of the record system on radiographic images sharpness by computer simulation is studied. The method intend to previously show the image to be obtained for each type of film or screen-film combination used during the exposure

  13. Load modeling for sharp V-cutter cutting litchi ( Litchi chinensis Sonn ...

    harvesting. Cutting load is a key parameter for 'hand-held auto-picker' operation. However, there is still no suitable model for cutting load setting. Hence, a model describing the relationship among cutting load, blade angle and friction coefficient was developed for cutting operation by sharp V-cutters. The model was based ...

  14. Conformal coating by photoresist of sharp corners of anisotropically etched through-holes in silicon

    Heschel, Matthias; Bouwstra, Siebe

    1997-01-01

    The authors describe a photoresist treatment yielding conformal coating of three-dimensional silicon structures. This even includes the sharp corners of through-holes obtained by anisotropic etching in (100)-silicon. Resist reflow from these corners is avoided by replacing the common baking...

  15. A new species of the genus Linoderus Sharp, 1885 (Coleoptera, Staphylinidae, Philonthina) from the Colombian Andes.

    López-García, Margarita M; Méndez-Rojas, Diana M

    2014-05-09

    The monotypic genus Linoderus Sharp, 1885 was described based on a species from Panama and since the original description nearly nothing has been added to its taxonomical knowledge. The aim of the present paper is to describe a new species of the genus from Colombia and to report the genus for the first time from South America, adding some biological notes of the species.

  16. Intercomparison of field measurements of nitrous acid (HONO) during the SHARP Campaign

    Because of the importance of HONO as a radical reservoir, consistent and accurate measurements of its concentration are needed. As part of the SHARP (Study of Houston Atmospheric Radical Precursors), time series of HONO were obtained by five different measurement techniques on th...

  17. Sharp Central Venous Recanalization in Hemodialysis Patients: A Single-Institution Experience

    Arabi, Mohammad, E-mail: marabi2004@hotmail.com; Ahmed, Ishtiaq; Mat’hami, Abdulaziz [Prince Sultan Military Medical City (PSMMC), Division of Endovascular Interventional Radiology, Department of Medical Imaging (Saudi Arabia); Ahmed, Dildar; Aslam, Naveed [Prince Sultan Military Medical City (PSMMC), Department of Nephrology (Saudi Arabia)

    2016-06-15

    PurposeWe report our institutional experience with sharp central venous recanalization in chronic hemodialysis patients who failed standard techniques.Materials and MethodsSince January 2014, a series of seven consecutive patients (four males and three females), mean age 35 years (18–65 years), underwent sharp central venous recanalization. Indications included obtaining hemodialysis access (n = 6) and restoration of superior vena cava (SVC) patency to alleviate occlusion symptoms and restore fistula function (n = 1). The transseptal needle was used for sharp recanalization in six patients, while it could not be introduced in one patient due to total occlusion of the inferior vena cava. Instead, transmediastinal SVC access using Chiba needle was obtained.ResultsTechnical success was achieved in all cases. SVC recanalization achieved symptoms’ relief and restored fistula function in the symptomatic patient. One patient underwent arteriovenous fistula creation on the recanalized side 3 months after the procedure. The remaining catheters were functional at median follow-up time of 9 months (1–14 months). Two major complications occurred including a right hemothorax and a small hemopericardium, which were managed by covered stent placement across the perforated SVC.ConclusionSharp central venous recanalization using the transseptal needle is feasible technique in patients who failed standard recanalization procedures. The potential high risk of complications necessitates thorough awareness of anatomy and proper technical preparedness.

  18. Development of the Children's Scale of Hostility and Aggression: Reactive/Proactive (C-SHARP)

    Farmer, Cristan A.; Aman, Michael G.

    2009-01-01

    Whereas some scales exist for assessing aggression in typically developing children, they do not give a detailed analysis, and none is available for populations with developmental disabilities (DD). Parents of 365 children with DD completed the Children's Scale of Hostility and Aggression: Reactive/Proactive (C-SHARP), which surveys the severity…

  19. Cryptic species of sharp-nosed reed frogs in the Hyperolius nasutus ...

    The sharp-nosed reed frog is widespread in Africa. Although currently recognized as one species, suggestions have been made that more than one species might exist. We analysed 237 calls of 69 males from 19 localities in the western to southern parts of Africa. Calls fall into three groups, which we recognize as cryptic ...

  20. Space-time adaptive hp-FEM for problems with traveling sharp fronts

    Šolín, Pavel; Korous, L.

    2013-01-01

    Roč. 95, č. 1 (2013), S709-S722 ISSN 0010-485X Institutional support: RVO:61388998 Keywords : adaptive hp-FEM * transient problems * sharp fronts Subject RIV: BA - General Mathematics Impact factor: 1.055, year: 2013

  1. A sharp Rogers–Shephard type inequality for Orlicz-difference body ...

    Abstract. In this paper, we prove a sharp Rogers–Shephard type inequality for the Orlicz-difference body of planar convex bodies, which extend the works of Bianchini and Colesanti (Proc. Amer. Math. Soc. 138(7) (2008) 2575–2582).

  2. Hydrovatus caraibus Sharp, 1882 (Dytiscidae, Hydroporinae, Hydrovatini new for the fauna of South America

    Benetti, C. J.

    2003-11-01

    Full Text Available The species Hydrovatus caraibus Sharp, 1882 is recorded for the first time for South America, after the recollection of specimens of this species in the municipality of Gramado, State of Rio Grande do Sul, Brazil. The range of distribution of the species, previously restricted to the Caribbean, is now extended to the latitude 29º 26’ South, approximately.

  3. Numerical deconvolution to enhance sharpness and contrast of portal images for radiotherapy patient positioning verification

    Looe, H.K.; Uphoff, Y.; Poppe, B.; Carl von Ossietzky Univ., Oldenburg; Harder, D.; Willborn, K.C.

    2012-01-01

    The quality of megavoltage clinical portal images is impaired by physical and geometrical effects. This image blurring can be corrected by a fast numerical two-dimensional (2D) deconvolution algorithm implemented in the electronic portal image device. We present some clinical examples of deconvolved portal images and evaluate the clinical advantages achieved by the improved sharpness and contrast. The principle of numerical 2D image deconvolution and the enhancement of sharpness and contrast thereby achieved are shortly explained. The key concept is the convolution kernel K(x,y), the mathematical equivalent of the smearing or blurring of a picture, and the computer-based elimination of this influence. Enhancements of sharpness and contrast were observed in all clinical portal images investigated. The images of fine bone structures were restored. The identification of organ boundaries and anatomical landmarks was improved, thereby permitting a more accurate comparison with the x-ray simulator radiographs. The visibility of prostate gold markers is also shown to be enhanced by deconvolution. The blurring effects of clinical portal images were eliminated by a numerical deconvolution algorithm that leads to better image sharpness and contrast. The fast algorithm permits the image blurring correction to be performed in real time, so that patient positioning verification with increased accuracy can be achieved in clinical practice. (orig.)

  4. Numerical deconvolution to enhance sharpness and contrast of portal images for radiotherapy patient positioning verification

    Looe, H.K.; Uphoff, Y.; Poppe, B. [Pius Hospital, Oldenburg (Germany). Clinic for Radiation Therapy; Carl von Ossietzky Univ., Oldenburg (Germany). WG Medical Radiation Physics; Harder, D. [Georg August Univ., Goettingen (Germany). Medical Physics and Biophysics; Willborn, K.C. [Pius Hospital, Oldenburg (Germany). Clinic for Radiation Therapy

    2012-02-15

    The quality of megavoltage clinical portal images is impaired by physical and geometrical effects. This image blurring can be corrected by a fast numerical two-dimensional (2D) deconvolution algorithm implemented in the electronic portal image device. We present some clinical examples of deconvolved portal images and evaluate the clinical advantages achieved by the improved sharpness and contrast. The principle of numerical 2D image deconvolution and the enhancement of sharpness and contrast thereby achieved are shortly explained. The key concept is the convolution kernel K(x,y), the mathematical equivalent of the smearing or blurring of a picture, and the computer-based elimination of this influence. Enhancements of sharpness and contrast were observed in all clinical portal images investigated. The images of fine bone structures were restored. The identification of organ boundaries and anatomical landmarks was improved, thereby permitting a more accurate comparison with the x-ray simulator radiographs. The visibility of prostate gold markers is also shown to be enhanced by deconvolution. The blurring effects of clinical portal images were eliminated by a numerical deconvolution algorithm that leads to better image sharpness and contrast. The fast algorithm permits the image blurring correction to be performed in real time, so that patient positioning verification with increased accuracy can be achieved in clinical practice. (orig.)

  5. Proliferation of sharp kinks on cosmic (super)string loops with junctions

    Binetruy, P.; Bohe, A.; Hertog, T.; Steer, D. A.

    2010-01-01

    Motivated by their effect on the gravitational wave signal emitted by cosmic strings, we study the dynamics of kinks on strings of different tensions meeting at junctions. The propagation of a kink through a Y junction leads to the formation of three 'daughter' kinks. Assuming a uniform distribution of the incoming wave vectors at the junction, we find there is a significant region of configuration space in which the sharpness of at least one of the daughter kinks is enhanced relative to the sharpness of the initial kink. For closed loops with junctions we show this leads to an exponential growth in time of very sharp kinks. Using numerical simulations of realistic, evolving cosmic string loops with junctions to calculate the distribution of kink amplitudes as a function of time, we show that loops of this kind typically develop several orders of magnitude of very sharp kinks before the two junctions collide. This collision, or other effects such as gravitational backreaction, may end the proliferation.

  6. Reversibility and hysteresis of the sharp yielding transition of a colloidal glass under oscillatory shear

    Dang, M. T.; Denisov, D.; Struth, B.; Zaccone, A.; Schall, P.

    The mechanical response of glasses remains challenging to understand. Recent results indicate that the oscillatory rheology of soft glasses is accompanied by a sharp non-equilibrium transition in the microscopic dynamics. Here, we use simultaneous x-ray scattering and rheology to investigate the

  7. Short-term responses of Dutch vacationers to a sharp increase in transport costs

    van Cranenburgh, S.

    2016-01-01

    This paper investigates vacationers’ short-term responses to a sharp increase in transport costs. It aims to (1) acquire an understanding of the relative popularity of the different types of responses among vacationers and (2) explore whether there are distinct market segments of vacationers that

  8. Sharp Central Venous Recanalization in Hemodialysis Patients: A Single-Institution Experience

    Arabi, Mohammad; Ahmed, Ishtiaq; Mat’hami, Abdulaziz; Ahmed, Dildar; Aslam, Naveed

    2016-01-01

    PurposeWe report our institutional experience with sharp central venous recanalization in chronic hemodialysis patients who failed standard techniques.Materials and MethodsSince January 2014, a series of seven consecutive patients (four males and three females), mean age 35 years (18–65 years), underwent sharp central venous recanalization. Indications included obtaining hemodialysis access (n = 6) and restoration of superior vena cava (SVC) patency to alleviate occlusion symptoms and restore fistula function (n = 1). The transseptal needle was used for sharp recanalization in six patients, while it could not be introduced in one patient due to total occlusion of the inferior vena cava. Instead, transmediastinal SVC access using Chiba needle was obtained.ResultsTechnical success was achieved in all cases. SVC recanalization achieved symptoms’ relief and restored fistula function in the symptomatic patient. One patient underwent arteriovenous fistula creation on the recanalized side 3 months after the procedure. The remaining catheters were functional at median follow-up time of 9 months (1–14 months). Two major complications occurred including a right hemothorax and a small hemopericardium, which were managed by covered stent placement across the perforated SVC.ConclusionSharp central venous recanalization using the transseptal needle is feasible technique in patients who failed standard recanalization procedures. The potential high risk of complications necessitates thorough awareness of anatomy and proper technical preparedness.

  9. The clinical application value of myocardial perfusion imaging in evaluating coronary artery myocardial bridge patients with symptoms

    Wang Yuetao; Fu Ning; Ding Xuemei; Lu Cunzhi; Zhu Feng; Wang Guanmin; Huang Yijie; Wang Linguang

    2008-01-01

    Objective: Myocardial bridge is a common inborn coronary artery anomaly, myocardial bridge may be associated with myocardial ischemia. Only a few patients with coronary artery myocardial bridge were evaluated with nuclear medicine techniques. The aim of this study was to investigate the role of nuclear cardiology with myocardial perfusion technique in symptomatic myocardial bridge patients. Methods Nineteen myocardial bridge patients with the symptoms of chest pain and chest distress were analyzed retrospectively. 99 Tc m -methoxyisobutylisonitrile (MIBI) myocardial perfusion images (both exercise and rest) were performed in all. Imaging results were compared with the results of movement electrocardiogram (ECG) and coronary arteriography. The t test or χ 2 test was used to statistically analyze the data with Stata 7.0 software. Results: Of the 19 patients, 18 patients had myocardial bridge locating at the left anterior descending artery, 1 patient at the left anterior descending and left circumflex artery, the mean angiographic systolic occlusion within the myocardial bridge was (65.4 ± 22.1)%. Of these 19 patients, Exercise-rest 99 Tc m -MIBI myocardial perfusion imaging defined positive myocardial ischemia in 10 and negative in 9 patients. Of the 10 patients with 99 Tc m -MIBI myocardial perfusion imaging defined myocardial ischemia, 8 had reversible radioactive defect of partial anterior wall and (or) apex, 1 had reversible defect of post lateral wall and post septal wall, and 1 had reversible defect of inferior wall. The positive predictive value of myocardial perfusion imaging was 52.6% (10/19), which was higher than movement ECG [21.1% (4/19), χ 2 = 4.07, P 99 Tc m -MIBI myocardial periusion imaging defined myocardial ischemia. Six cases with Grade II stenosis, two were 99 Tc m -MIBI myocardial perfusion imaging defined myocardial ischemia. Eight cases with Grade III stenosis, seven were 99 Tc m -MIBI myocardial perfusion imaging defined myocardial

  10. Quantitative aspects of myocardial perfusion imaging

    Vogel, R.A.

    1980-01-01

    Myocardial perfusion measurements have traditionally been performed in a quantitative fashion using application of the Sapirstein, Fick, Kety-Schmidt, or compartmental analysis principles. Although global myocardial blood flow measurements have not proven clinically useful, regional determinations have substantially advanced our understanding of and ability to detect myocardial ischemia. With the introduction of thallium-201, such studies have become widely available, although these have generally undergone qualitative evaluation. Using computer-digitized data, several methods for the quantification of myocardial perfusion images have been introduced. These include orthogonal and polar coordinate systems and anatomically oriented region of interest segmentation. Statistical ranges of normal and time-activity analyses have been applied to these data, resulting in objective and reproducible means of data evaluation

  11. Myocardial perfusion scintigraphy - possibilities of diagnosing CAD

    Tsonevska, A.

    1998-01-01

    A reviewing the diagnostic methods used in the intricate process of evaluating CAD patients in a attempt to establish the role played by radionuclide methods in the diagnostic strategy is done. The perfusion cardiotropic radiopharmaceuticals used and the various methods of evaluating myocardial are discussed. Although 210 Tl-chloride is the most widely used myocardial perfusion agent, recently 99m Tc-MIBI is proposed as an alternative because of its advantages. Myocardial perfusion assessment is done by various techniques depending on the specific aim, each of them having its proper advantages and shortcomings. The inference is reached that regardless of the routine practical implementation of myocardial perfusion scintigraphy and comprehensive studies along this line in course, there are problems still not well enough clarified awaiting solution

  12. The Pathogenesis of Human Myocardial Infarction

    Rona, George

    1966-01-01

    Coronary arteriography, dissection of the coronary arteries and histopathological examination of the heart were carried out in 150 autopsies to study the effect of coronary narrowing and occlusion, of the presence of collaterals, and of coronary artery predominance on the development of myocardial infarction. The thrombosis rate was related to the severity of coronary sclerosis. The development of collaterals was not enhanced by coronary sclerosis and occlusion, and collaterals did not protect the myocardium against reinfarction. Coronary occlusion was regularly demonstrable in recent myocardial infarct cases. The association of atrial and posterior ventricular infarcts was explained by occlusion of their common arterial branch. The interdependence between coronary sclerosis, thrombosis and myocardial infarction in human autopsy material emphasizes the importance of mural coronary artery disease in the genesis of coronary occlusion and myocardial infarction, and it is at variance with statistical data and experimental results. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6 PMID:5924947

  13. DEPRESSIVE DISORDERS IN PATIENTS AFTER MYOCARDIAL INFARCTION

    MUXAMADIYEVA NIGINA BAKHODIROVNA

    2016-01-01

    In article the depressions arising at patients after a myocardial infarction (MI) are shined, necessity of overcoming stigma concerning weight of the transferred MI, rational under-standing of illness especially in early period of the post infraction is defined.

  14. Notes on breeding sharp-shinned hawks and cooper’s hawks in Barnwell County, South Carolina

    Mark Vukovich; John C. Kilgo

    2009-01-01

    Breeding records of Accipiter striatus (Sharp-shinned Hawks) in the southeastern US are scattered and isolated. We documented a Sharp-shinned Hawk and Accipiter cooperii (Cooper’s Hawk) nest while conducting a telemetry study on Melanerpes erythrocephalus (Red-headed Woodpeckers) in Barnwell County, SC in 2006 and 2007. We report the first known nest of a Sharp-shinned...

  15. Cannula Versus Sharp Needle for Placement of Soft Tissue Fillers: An Observational Cadaver Study.

    van Loghem, Jani A J; Humzah, Dalvi; Kerscher, Martina

    2017-12-13

    Soft-tissue fillers have become important products for facial rejuvenation. Deep fat compartments and facial bones lose volume during the natural aging process. For the most natural-looking results, deep volumetric injections at strategic sites are therefore preferred. Supraperiosteal placement is performed with a sharp needle or a non-traumatic cannula. The primary objective was to determine whether there is a difference in precision between supraperiosteal placement with a sharp needle compared with a non-traumatic cannula in cadaver specimens. A secondary objective was to analyze the safety profiles of both injection techniques. Cadaver heads were injected with dye material and soft-tissue fillers at multiple aesthetic facial sites on the supraperiosteum and subsequently dissected for observation of dye and filler placement. The non-traumatic cannula technique resulted in product being confined to the deep anatomic layers. In contrast, with the sharp needle technique, material was placed in multiple anatomic layers, from the periosteum to more superficial skin layers. For both techniques results were consistent for all facial sites. Although direct extrapolation from cadavers to the in vivo situation cannot be made, cannulae showed more precision in placement of product. With the sharp needle, the material was injected on the periosteum, and then migrated in a retrograde direction along the trajectory of the needle path, ending up in multiple anatomic layers. The sharp needle technique also showed a higher complication risk with intra-arterial injection occurring, even though the needle tip was positioned on the periosteum and the product was injected with the needle in constant contact with the periosteum. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com

  16. Echocardiography diagnosis of myocardial infarction complications

    N.D. Oryshchyn

    2016-03-01

    Full Text Available Diagnosis and management of myocardial infarction complications are discussed in this article. These complications are associated with high level of mortality and surgery is a main treatment method. High level of suspicion and early diagnosis are essential for appropriate treatment and improvement of prognosis. Echocardiography is a main diagnostic method. Analysis of literature about contemporary management of mechanical complications of myocardial infarction has been performed, case reports are presented.

  17. Acute myocardial infarction: 'telomerasing' for cardioprotection

    Sanchís-Gomar, Fabián; Lucía Mulas, Alejandro

    2015-01-01

    Reactivating the telomerase gene through gene therapy after acute myocardial infarction (AMI) has been recently reported to improve survival in mice. Given that regular physical exercise also activates this gene, therapeutic and lifestyle interventions targeting telomerase need to be explored as possible additions to the current armamentarium for myocardial regeneration. 9.292 JCR (2015) Q1, 17/289 Biochemistry & mollecular biology, 17/187 Cell biology, 8/124 Medicine, research & experimen...

  18. Improved exercise myocardial perfusion during lidoflazine therapy

    Shapiro, W.; Narahara, K.A.; Park, J.

    1983-01-01

    Lidoflazine is a synthetic drug with calcium-channel blocking effects. In a study of 6 patients with severe classic angina pectoris, single-blind administration of lidoflazine was associated with improved myocardial perfusion during exercise as determined by thallium-201 stress scintigraphy. These studies demonstrate that lidoflazine therapy is associated with relief of angina, an increased physical work capacity, and improved regional myocardial perfusion during exercise

  19. Measurement of myocardial perfusion using magnetic resonance

    Fritz-Hansen, T.; Jensen, L.T.; Larsson, H.B.

    2008-01-01

    Cardiac magnetic resonance imaging (MRI) has evolved rapidly. Recent developments have made non-invasive quantitative myocardial perfusion measurements possible. MRI is particularly attractive due to its high spatial resolution and because it does not involve ionising radiation. This paper reviews...... myocardial perfusion imaging with MR contrast agents: methods, validation and experiences from clinical studies. Unresolved issues still restrict the use of these techniques to research although clinical applications are within reach Udgivelsesdato: 2008/12/8...

  20. Towards quantitative off-axis electron holographic mapping of the electric field around the tip of a sharp biased metallic needle

    Beleggia, Marco; Kasama, Takeshi; Larson, D. J.

    2014-01-01

    We apply off-axis electron holography and Lorentz microscopy in the transmission electron microscope to map the electric field generated by a sharp biased metallic tip. A combination of experimental data and modelling provides quantitative information about the potential and the field around...... the tip. Close to the tip apex, we measure a maximum field intensity of 82 MV/m, corresponding to a field k factor of 2.5, in excellent agreement with theory. In order to verify the validity of the measurements, we use the inferred charge density distribution in the tip region to generate simulated phase...

  1. Automated quantitative coronary computed tomography correlates of myocardial ischaemia on gated myocardial perfusion SPECT

    Graaf, Michiel A. de; Boogers, Mark J.; Veltman, Caroline E.; El-Naggar, Heba M.; Bax, Jeroen J.; Delgado, Victoria; Broersen, Alexander; Kitslaar, Pieter H.; Dijkstra, Jouke; Kroft, Lucia J.; Younis, Imad Al; Reiber, Johan H.; Scholte, Arthur J.

    2013-01-01

    Automated software tools have permitted more comprehensive, robust and reproducible quantification of coronary stenosis, plaque burden and plaque location of coronary computed tomography angiography (CTA) data. The association between these quantitative CTA (QCT) parameters and the presence of myocardial ischaemia has not been explored. The aim of the present investigation was to evaluate the association between QCT parameters of coronary artery lesions and the presence of myocardial ischaemia on gated myocardial perfusion single-photon emission CT (SPECT). Included in the study were 40 patients (mean age 58.2 ± 10.9 years, 27 men) with known or suspected coronary artery disease (CAD) who had undergone multidetector row CTA and gated myocardial perfusion SPECT within 6 months. From the CTA datasets, vessel-based and lesion-based visual analyses were performed. Consecutively, lesion-based QCT was performed to assess plaque length, plaque burden, percentage lumen area stenosis and remodelling index. Subsequently, the presence of myocardial ischaemia was assessed using the summed difference score (SDS ≥2) on gated myocardial perfusion SPECT. Myocardial ischaemia was seen in 25 patients (62.5 %) in 37 vascular territories. Quantitatively assessed significant stenosis and quantitatively assessed lesion length were independently associated with myocardial ischaemia (OR 7.72, 95 % CI 2.41-24.7, p 2 = 20.7) and lesion length (χ 2 = 26.0) to the clinical variables and the visual assessment (χ 2 = 5.9) had incremental value in the association with myocardial ischaemia. Coronary lesion length and quantitatively assessed significant stenosis were independently associated with myocardial ischaemia. Both quantitative parameters have incremental value over baseline variables and visually assessed significant stenosis. Potentially, QCT can refine assessment of CAD, which may be of potential use for identification of patients with myocardial ischaemia. (orig.)

  2. Effect of eating on thallium myocardial imaging

    Wilson, R.A.; Sullivan, P.J.; Okada, R.D.; Boucher, C.A.; Morris, C.; Pohost, G.M.; Strauss, H.W.

    1986-01-01

    To determine if eating between initial and delayed thallium images alters the appearance of the delayed thallium scan, a prospective study was performed; 184 subjects sent for routine thallium imaging were randomized into two groups, those who ate a meal high in carbohydrates between initial and delayed thallium myocardial images (n = 106), and those who fasted (n = 78). The 201 Tl images were interpreted in blinded fashion for global myocardial and pulmonary clearance of 201 Tl myocardial defects. The eating group had a significantly lower incidence of transient myocardial defects compared to the noneating group (7 percent vs 18 percent, respectively; p less than 0.05). The time between initial and delayed images and the incidence of exercise-induced ischemic ST-segment depression or pathologic Q waves on the electrocardiogram were not significantly different between the two groups. These data suggest that eating a high-carbohydrate meal between initial and delayed 201 Tl images causes increased 201 Tl myocardial clearance rates and may alter 201 Tl myocardial redistribution over time

  3. Myocardial infarction in Swedish subway drivers.

    Bigert, Carolina; Klerdal, Kristina; Hammar, Niklas; Gustavsson, Per

    2007-08-01

    Particulate matter in urban air is associated with the risk of myocardial infarction in the general population. Very high levels of airborne particles have been detected in the subway system of Stockholm, as well as in several other large cities. This situation has caused concern for negative health effects among subway staff. The aim of this study was to investigate whether there is an increased incidence of myocardial infarction among subway drivers. Data from a population-based case-control study of men aged 40-69 in Stockholm County in 1976-1996 were used. The study included all first events of myocardial infarction in registers of hospital discharges and deaths. The controls were selected randomly from the general population. National censuses were used for information on occupation. Altogether, 22 311 cases and 131 496 controls were included. Among these, 54 cases and 250 controls had worked as subway drivers. The relative risk of myocardial infarction among subway drivers was not increased. It was 0.92 [95% confidence interval (95% CI) 0.68-1.25] when the subway drivers were compared with other manual workers and 1.06 (95% CI 0.78-1.43) when the subway drivers were compared with all other gainfully employed men. Subgroup analyses indicated no influence on the risk of myocardial infarction from the duration of employment, latency time, or time since employment stopped. Subway drivers in Stockholm do not have a higher incidence of myocardial infarction than other employed persons.

  4. Quantitative myocardial blood flow with Rubidium-82 PET

    Hagemann, Christoffer E; Ghotbi, Adam A; Kjær, Andreas

    2015-01-01

    Positron emission tomography (PET) allows assessment of myocardial blood flow in absolute terms (ml/min/g). Quantification of myocardial blood flow (MBF) and myocardial flow reserve (MFR) extend the scope of conventional semi-quantitative myocardial perfusion imaging (MPI): e.g. in 1) identificat......Positron emission tomography (PET) allows assessment of myocardial blood flow in absolute terms (ml/min/g). Quantification of myocardial blood flow (MBF) and myocardial flow reserve (MFR) extend the scope of conventional semi-quantitative myocardial perfusion imaging (MPI): e.g. in 1...... global MFR and major adverse cardiovascular events (MACE), and together with new diagnostic possibilities from measuring the longitudinal myocardial perfusion gradient, cardiac (82)Rb PET faces a promising clinical future. This article reviews current evidence on quantitative (82)Rb PET's ability...

  5. Mitochondrial Membrane Permeability Inhibitors in Acute Myocardial Infarction

    Cory Trankle, MD

    2016-10-01

    Full Text Available Despite therapeutic advances, acute myocardial infarction (AMI remains a leading cause of morbidity and mortality worldwide. One potential limitation of the current treatment paradigm is the lack of effective therapies to optimize reperfusion after ischemia and prevent reperfusion-mediated injury. Experimental studies indicate that this process accounts for up to 50% of the final infarct size, lending it importance as a potential target for cardioprotection. However, multiple therapeutic approaches have shown potential in pre-clinical and early phase trials but a paucity of clear clinical benefit when expanded to larger studies. Here we explore this history of trials and errors of the studies of cyclosporine A and other mitochondrial membrane permeability inhibitors, agents that appeared to have a promising pre-clinical record yet provided disappointing results in phase III clinical trials.

  6. Applicability of myocardial perfusion scintigraphy in the evaluation of cardiac synchronization

    Reis, Christiane Cigagna Wiefels; Nascimento, Erivelton Alessandro do; Dias, Fernanda Baptista Ribeiro; Ribeiro, Mario Luiz; Wanderley, Annelise Passos Bispo; Batista, Layanara Albino; Nunes, Thais Helena Peixoto; Mesquita, Claudio Tinoco, E-mail: chriswreis@gmail.com [Universidade Federal Fluminense (UFF), Niterói, RJ (Brazil). Hospital Universitário Antônio Pedro

    2017-07-15

    To systematically assess the literature on the applicability of myocardial perfusion scintigraphy with phase analysis in the investigation of cardiac dyssynchrony and in the selection of patients for cardiac resynchronization therapy (CRT), manuscripts published on the PubMed database over the past five years have been reviewed. The following MeSH terms were used: heart failure, left ventricular, dyssynchrony, gated-SPECT, phase analysis and resynchronization therapy. Altogether, 99 manuscripts were included for discussion. Speckle-tracking echocardiography is still widely used in the evaluation of dyssynchrony, but the advent of myocardial perfusion scintigraphy with the phase analysis technique has been gaining ground, as besides being operator independent, it can evaluate myocardial viability in the same test. Its use became more widespread in patients with left bundle branch block, with recommendation of CRT. Phase analysis also allows evaluating, in a highly reproducible way, the last ventricular segment to contract, hence allowing the best positioning of the CRT electrode. Knowing that the presence, location and extent of fibrosis in the left ventricle, associated with dyssynchrony are determinants of response to resynchronization therapy, GATED- SPECT can provide this information in a single test and in a reproducible and accurate way. Phase histogram offers several parameters that provide greater sensitivity and specificity to the method. It seems that the technique is able to add value both in the selection and in the evaluation of response of patients eligible to CRT. Further studies are being conducted to demonstrate its clinical applicability. (author)

  7. Quantifying the margin sharpness of lesions on radiological images for content-based image retrieval

    Xu Jiajing; Napel, Sandy; Greenspan, Hayit; Beaulieu, Christopher F.; Agrawal, Neeraj; Rubin, Daniel

    2012-01-01

    Purpose: To develop a method to quantify the margin sharpness of lesions on CT and to evaluate it in simulations and CT scans of liver and lung lesions. Methods: The authors computed two attributes of margin sharpness: the intensity difference between a lesion and its surroundings, and the sharpness of the intensity transition across the lesion boundary. These two attributes were extracted from sigmoid curves fitted along lines automatically drawn orthogonal to the lesion margin. The authors then represented the margin characteristics for each lesion by a feature vector containing histograms of these parameters. The authors created 100 simulated CT scans of lesions over a range of intensity difference and margin sharpness, and used the concordance correlation between the known parameter and the corresponding computed feature as a measure of performance. The authors also evaluated their method in 79 liver lesions (44 patients: 23 M, 21 F, mean age 61) and 58 lung nodules (57 patients: 24 M, 33 F, mean age 66). The methodology presented takes into consideration the boundary of the liver and lung during feature extraction in clinical images to ensure that the margin feature do not get contaminated by anatomy other than the normal organ surrounding the lesions. For evaluation in these clinical images, the authors created subjective independent reference standards for pairwise margin sharpness similarity in the liver and lung cohorts, and compared rank orderings of similarity used using our sharpness feature to that expected from the reference standards using mean normalized discounted cumulative gain (NDCG) over all query images. In addition, the authors compared their proposed feature with two existing techniques for lesion margin characterization using the simulated and clinical datasets. The authors also evaluated the robustness of their features against variations in delineation of the lesion margin by simulating five types of deformations of the lesion margin

  8. Myocardial adrenergic nerve activity in valvular diseases assessed by iodine-123-metaiodobenzylguanidine myocardial scintigraphy

    Imamura, Yoshihiro; Fukuyama, Takaya

    1997-01-01

    Iodine-123-metaiodobenzylguanidine (MIBG) imaging was used to assess myocardial adrenergic nerve activity in patients with heart failure. MIBG planar images were obtained in 94 patients. The uptake of MIBG, calculated as the heart-to-mediastinum activity ratio in the immediate image (15 min), showed a significant decrease only in patients with severe heart failure due to cardiomyopathy, but was not changed in those with valvular diseases. Storage and release of MIBG, calculated as the percentage myocardial MIBG washout from 15 min to 4 hours after isotope injection, was substantially accelerated in both patients with cardiomyopathy and valvular diseases in proportion to the severity of heart failure. These data suggest that, in severe heart failure associated with cardiomyopathy, norepinephrine uptake is reduced. Also, myocardial adrenergic nerve activity is accelerated in proportion to the severity of heart failure independent of the underlying cause. MIBG images were analyzed in 20 patients with mitral stenosis with the same methods to clarify whether myocardial adrenergic nerve activity is different in patients with heart failure without left ventricular volume or pressure overload. Myocardial uptake of MIBG did not show any significant difference. The percentage myocardial MIBG washout was increased in patients with severe heart failure. The closest correlation was between myocardial washout and cardiac output. In heart failure due to mitral stenosis, myocardial adrenergic nerve activity is intensified. Decrease in cardiac output associated with mitral stenosis acts as a potent stimulus for this intensification. (author)

  9. The diagnosis of silent myocardial ischemia. Motion-Frozen (or morphing) myocardial perfusion imaging.

    Chang, Cheng; Ye, Bo; Xie, Wenhui; Zhang, Daoliang; Lei, Bei; Ye, Xiaodan

    2016-01-01

    Silent myocardial ischemia is typically defined as objective evidence of myocardial ischemia in patients without subjective ischemia symptoms. Currently, coronary artery angiography is the gold standard for diagnosis of asymptomatic coronary artery disease (CAD). Computed tomography coronary angiography (CTCA) can visually demonstrate the morphology, trend and extent of coronary stenosis and is commonly used in clinical screening of CAD. Myocardial perfusion imaging can be used not only to identify whether anatomical stenosis causes myocardial dysfunction, but to also assess the risk stratification and prognosis of myocardial disease (MD). Myocardial perfusion imaging using morphing combined with CTCA can simultaneously show the relationship between CAD and myocardial ischemia from an anatomical and functional aspect. This allows earlier diagnosis of asymptomatic CAD myocardial ischemia, accurate identification of the culprit vessels, and could prevent unnecessary interventional therapy. The 1-day dobutamine stress/resting met-hod is also one of the methods used. The combination of CTCA and the morphing technique can provide anatomical and functional information on coronary arteries at the same time, significantly improving the diagnostic sensitivity, specificity, and accuracy of MD.

  10. Application of the SHARP Toolkit to Sodium-Cooled Fast Reactor Challenge Problems

    Shemon, E. R. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Yu, Y. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Kim, T. K. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

    2017-09-30

    The Simulation-based High-efficiency Advanced Reactor Prototyping (SHARP) toolkit is under development by the Nuclear Energy Advanced Modeling and Simulation (NEAMS) Campaign of the U.S. Department of Energy, Office of Nuclear Energy. To better understand and exploit the benefits of advanced modeling simulations, the NEAMS Campaign initiated the “Sodium-Cooled Fast Reactor (SFR) Challenge Problems” task, which include the assessment of hot channel factors (HCFs) and the demonstration of zooming capability using the SHARP toolkit. If both challenge problems are resolved through advanced modeling and simulation using the SHARP toolkit, the economic competitiveness of a SFR can be significantly improved. The efforts in the first year of this project focused on the development of computational models, meshes, and coupling procedures for multi-physics calculations using the neutronics (PROTEUS) and thermal-hydraulic (Nek5000) components of the SHARP toolkit, as well as demonstration of the HCF calculation capability for the 100 MWe Advanced Fast Reactor (AFR-100) design. Testing the feasibility of the SHARP zooming capability is planned in FY 2018. The HCFs developed for the earlier SFRs (FFTF, CRBR, and EBR-II) were reviewed, and a subset of these were identified as potential candidates for reduction or elimination through high-fidelity simulations. A one-way offline coupling method was used to evaluate the HCFs where the neutronics solver PROTEUS computes the power profile based on an assumed temperature, and the computational fluid dynamics solver Nek5000 evaluates the peak temperatures using the neutronics power profile. If the initial temperature profile used in the neutronics calculation is reasonably accurate, the one-way offline method is valid because the neutronics power profile has weak dependence on small temperature variation. In order to get more precise results, the proper temperature profile for initial neutronics calculations was obtained from the

  11. Prognostic impact of physical activity prior to myocardial infarction

    Ejlersen, Hanne; Andersen, Zorana Jovanovic; von Euler-Chelpin, My Catarina

    2017-01-01

    the course of myocardial infarction by reducing case fatality and the subsequent risk of heart failure and mortality. Methods: A total of 14,223 participants in the Copenhagen City Heart Study were assessed at baseline in 1976-1978; 1,664 later developed myocardial infarction (mean age at myocardial...... estimated by logistic and Cox proportional hazards regression models, adjusted for age at myocardial infarction and other potential confounders. Results: A total of 425 (25.5%) myocardial infarctions were fatal. Higher levels of LTPA prior to myocardial infarction were associated with lower case fatality...

  12. Evaluation of myocardial involvement in Duchenne's progressive muscular dystrophy with thallium-201 myocardial perfusion imaging

    Kawai, Naoki; Sotobata, Iwao; Okada, Mitsuhiro

    1985-01-01

    Myocardial involvement in progressive muscular dystrophy of the Duchenne type was evaluated in 19 patients using thallium-201 myocardial perfusion imaging. A qualitative analysis was performed from five projection images by three experienced physicians. Distinct perfusion defects were shown in 13 patients, especially in the LV posterolateral or posterior wall (11 patients). There was no significant relationship between the presence of perfusion defects and the skeletal muscle involvements or thoracic deformities assessed by transmission computed tomography. Extensive perfusion defects were shown in 2 patients who died of congestive heart failure 1 to 2 years after the scintigraphic study. Progression of the myocardial scintigraphic abnormalities were considered to be minimal in 7 of 9 patients who underwent two serial scintigraphic studies over 2 to 3 years. It was concluded that thallium myocardial perfusion imaging is a useful clinical technique to assess myocardial involvement in Duchenne's progressive muscular dystrophy. (author)

  13. Localization and quantification of acute myocardial infarction by myocardial perfusion tomographic imaging

    Lin Xiufang; Min Changgeng; Lin Zhihu; Ke Ruoyi

    1994-01-01

    The authors reported the result of the quantification and localization of 30 clinically confirmed acute myocardial infarction patients in comparison with that of ECG. A left ventricle model was used to correct the area calculated by the method of Bull's eye. The result indicated that the infarction area calculated by the corrected Bull's eye method correlated closely with that determined by the ECG QRS scoring method (r = 0.706, P<0.01). Myocardial infarctions of all 30 patients were detected by both ECG and myocardial perfusion tomographic imaging. The accuracy of localization of myocardial infarction by myocardial perfusion imaging was similar to that of ECG in the anterior wall, anterior septum, anterior lateral and inferior wall, but superior to that of ECG in the apex, posterior lateral, posterior septum, and posterior wall

  14. [Genetic factors in myocardial infarction].

    Hara, Masahiko; Sakata, Yasuhiko; Sato, Hiroshi

    2013-02-01

    One of the main mechanisms of acute myocardial infarction (AMI) is plaque rupture or erosion followed by intraluminal thrombus formation and occlusion of the coronary arteries. Thus far, many underlying conditions or environmental factors, such as hypertension, diabetes, dyslipidemia, smoking or obesity, as well as a family history of coronary artery diseases have been identified as risks for the onset of AMI. These risks suggest that AMI occurs due to interactions between underlying conditions and multiple genetic susceptibilities. For this reason, many target gene-disease association studies have been performed with the recent introduction of genome-wide association studies (GWAS) that have further revealed new genetic susceptibilities for AMI. GWAS is a way to examine many common genetic variants in different individuals to see if any variant is associated with a trait in a case-control fashion, and typically focuses on associations between single-nucleotide polymorphisms (SNP) and traits. SNP on chromosome 9p21 is one of the robust susceptibility variants for AMI which has been identified by many GWAS. In this review, we overview the methodology of GWAS, introduce genetic variants identified by GWAS as those with susceptibility for AMI, and describe the foresight of using GWAS to investigate genetic susceptibility to AMI.

  15. Tl myocardial SPECT demonstrates importance of collateral circulation in patients with myocardial infarction

    Hattori, Fukunori

    1997-01-01

    The influence of collateral circulation on the preservation of myocardial viability and the efficacy of drug therapy and PTCA were evaluated by exercise 201 Tl myocardial SPECT before and after treatment. Thirty-five patients with a history of myocardial infarction resulting from total or subtotal obstruction of the responsible coronary artery were divided into four groups, according to the method of the treatment and the degree of collateral blood flow. Patients in groups A and B received drug therapy and displayed developed and undeveloped collateral circulation, respectively. Groups C and D received PTCA and displayed developed and undeveloped collateral circulation, respectively. Tl myocardial SPECT was performed before treatment to record the extent of redistribution to the occluded region, the degree of myocardial viability and the nature and extent of the ischemic lesion. In group A, myocardial perfusion improved, although redistribution remained in all cases, while in group B, 4 of 7 cases improved after drug therapy. In group C, myocardial perfusion improved in all cases, and redistribution disappeared in 7 of 12 cases. 5 of 6 cases improved in group D after PTCA. After drug therapy, the %Tl uptake in the infarcted region improved significantly in initial and delayed images of patients in group A. The differences in initial and delayed images in group B before and after drug therapy were not significant. In contrast, groups C and D both registered significant improvement in initial and delayed images after PTCA. The washout rate improved significantly in groups A, C and D after their respective treatments. These results suggest that developed collateral circulation helps to preserve myocardial viability in cases of myocardial infarction. Myocardial perfusion improved after drug therapy in cases with developed collateral circulation, and in patients with developed and undeveloped collateral circulation receiving PTCA. (K.H.)

  16. Biphasic thallium 201 SPECT-imaging for the noninvasive diagnosis of myocardial perfusion abnormalities in a child with Kawasaki disease--a case report

    Hausdorf, G.; Nienaber, C.A.; Spielman, R.P.

    1988-01-01

    The mucocutaneous lymph node syndrome (Kawasaki disease) is of increasing importance for the pediatric cardiologist, for coronary aneurysms with the potential of thrombosis and subsequent stenosis can develop in the course of the disease. The authors report a 2 1/2-year-old female child in whom, fourteen months after the acute phase of Kawasaki disease, myocardial infarction occurred. Biphasic thallium 201 SPECT-imaging using dipyridamole depicted anterior wall ischemia and inferolateral infarction. This case demonstrates that noninvasive vasodilation-redistribution thallium 201 SPECT-imaging has the potential to predict reversible myocardial perfusion defects and myocardial necrosis, even in small infants with Kawasaki disease

  17. Study of hydrodynamic characteristics of a Sharp Eagle wave energy converter

    Zhang, Ya-qun; Sheng, Song-wei; You, Ya-ge; Huang, Zhen-xin; Wang, Wen-sheng

    2017-06-01

    According to Newton's Second Law and the microwave theory, mechanical analysis of multiple buoys which form Sharp Eagle wave energy converter (WEC) is carried out. The movements of every buoy in three modes couple each other when they are affected with incident waves. Based on the above, mechanical models of the WEC are established, which are concerned with fluid forces, damping forces, hinge forces, and so on. Hydrodynamic parameters of one buoy are obtained by taking the other moving buoy as boundary conditions. Then, by taking those hydrodynamic parameters into the mechanical models, the optimum external damping and optimal capture width ratio are calculated out. Under the condition of the optimum external damping, a plenty of data are obtained, such as the displacements amplitude of each buoy in three modes (sway, heave, pitch), damping forces, hinge forces, and speed of the hydraulic cylinder. Research results provide theoretical references and basis for Sharp Eagle WECs in the design and manufacture.

  18. Multi-Physics Demonstration Problem with the SHARP Reactor Simulation Toolkit

    Merzari, E. [Argonne National Lab. (ANL), Argonne, IL (United States); Shemon, E. R. [Argonne National Lab. (ANL), Argonne, IL (United States); Yu, Y. Q. [Argonne National Lab. (ANL), Argonne, IL (United States); Thomas, J. W. [Argonne National Lab. (ANL), Argonne, IL (United States); Obabko, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Jain, Rajeev [Argonne National Lab. (ANL), Argonne, IL (United States); Mahadevan, Vijay [Argonne National Lab. (ANL), Argonne, IL (United States); Tautges, Timothy [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Solberg, Jerome [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ferencz, Robert Mark [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Whitesides, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-12-21

    This report describes to employ SHARP to perform a first-of-a-kind analysis of the core radial expansion phenomenon in an SFR. This effort required significant advances in the framework Multi-Physics Demonstration Problem with the SHARP Reactor Simulation Toolkit used to drive the coupled simulations, manipulate the mesh in response to the deformation of the geometry, and generate the necessary modified mesh files. Furthermore, the model geometry is fairly complex, and consistent mesh generation for the three physics modules required significant effort. Fully-integrated simulations of a 7-assembly mini-core test problem have been performed, and the results are presented here. Physics models of a full-core model of the Advanced Burner Test Reactor have also been developed for each of the three physics modules. Standalone results of each of the three physics modules for the ABTR are presented here, which provides a demonstration of the feasibility of the fully-integrated simulation.

  19. The 1985 National Aeronautics and Space Administration's Summer High School Apprenticeship Research Program (SHARP)

    1985-01-01

    In 1985, a total of 126 talented high school students gained first hand knowledge about science and engineering careers by working directly with a NASA scientist or engineer during the summer. This marked the sixth year of operation for NASA's Summer High School Apprenticeship Research Program (SHARP). The major priority of maintaining the high standards and success of prior years was satisfied. The following eight sites participated in the Program: Ames Research Center, Ames' Dryden Flight Research Facility, Goddard Space Flight Center, Goddard's Wallop Flight Facility, Kennedy Space Center, Langley Research Center, Lewis Research Center, and Marshall Space Flight Center. Tresp Associates served as the SHARP contractor and worked closely with NASA staff at headquarters and the sites just mentioned to plan, implement, and evaluate the program.

  20. Sensitivity of using blunt and sharp crack models in elastic-plastic fracture mechanics

    Pan, Y.C.; Kennedy, J.M.; Marchertas, A.H.

    1985-01-01

    J-integral values are calculated for both the blunt (smeared) crack and the sharp (discrete) crack models in elastic-plastic fracture mechanics problems involving metallic materials. A sensitivity study is performed to show the relative strengths and weaknesses of the two cracking models. It is concluded that the blunt crack model is less dependent on the orientation of the mesh. For the mesh which is in line with the crack direction, however, the sharp crack model is less sensitive to the mesh size. Both models yield reasonable results for a properly discretized finite-element mesh. A subcycling technique is used in this study in the explicit integration scheme so that large time steps can be used for the coarse elements away from the crack tip. The savings of computation time by this technique are reported. 6 refs., 9 figs

  1. Growth of aluminum oxide on silicon carbide with an atomically sharp interface

    Silva, Ana Gomes; Pedersen, Kjeld; Li, Zheshen

    2017-01-01

    this system up to around 600 °C (all in ultrahigh vacuum). This converts all the SiO2 into a uniform layer of Al2O3 with an atomically sharp interface between the Al2O3 and the Si surface. In the present work, the same procedures are applied to form Al2O3 on a SiC film grown on top of Si (111). The results...... indicate that a similar process, resulting in a uniform layer of 1-2 nm of Al2O3 with an atomically sharp Al2O3/SiC interface, also works in this case.......The development of SiC wafers with properties suitable for electronic device fabrication is now well established commercially. A critical issue for developing metal-oxide-semiconductor field effect transistor devices of SiC is the choice of dielectric materials for surface passivation...

  2. Sharp Absorption Peaks in THz Spectra Valuable for Crystal Quality Evaluation of Middle Molecular Weight Pharmaceuticals

    Sasaki, Tetsuo; Sakamoto, Tomoaki; Otsuka, Makoto

    2018-05-01

    Middle molecular weight (MMW) pharmaceuticals (MW 400 4000) are attracting attention for their possible use in new medications. Sharp absorption peaks were observed in MMW pharmaceuticals at low temperatures by measuring with a high-resolution terahertz (THz) spectrometer. As examples, high-resolution THz spectra for amoxicillin trihydrate, atorvastatin calcium trihydrate, probucol, and α,β,γ,δ-tetrakis(1-methylpyridinium-4-yl)porphyrin p-toluenesulfonate (TMPyP) were obtained at 10 K. Typically observed as peaks with full width at half-height (FWHM) values as low as 5.639 GHz at 0.96492 THz in amoxicillin trihydrate and 8.857 GHz at 1.07974 THz for probucol, many sharp peaks of MMW pharmaceuticals could be observed. Such narrow absorption peaks enable evaluation of the crystal quality of MMW pharmaceuticals and afford sensitive detection of impurities.

  3. Feeding ecology of sharp-shinned hawks in deciduous and coniferous forests in Colorado

    Suzanne M. Joy; Richard T. Reynolds; Richard L. Knight; Richard W. Hoffman

    1994-01-01

    Feeding ecology of 11 Sharp-skinned Hawk (Accipiter striates) pairs nesting in aspen (Populus tremuloides), conifer (Abies, Picea spp.), and mixed aspen-conifer habitats in southwest Colorado was investigated during 1988-1989. Small birds (x-bar = 20.9 g, SE = 0.8 g) and mammals (x-bar = 41.1 g, SE = 3.3 g) comprised 91 and 9% of...

  4. Driving Skills Training for Older Adults: An Assessment of DriveSharp.

    Johnston, Katherine A; Borkenhagen, David; Scialfa, Charles T

    2015-12-01

    RÉSUMÉ Les procédures de formation cognitive informatique visent à augmenter la sécurité en améliorant les compétences relatives à la conduite, comme la vitesse-de-traitement et le Useful Field of View. L'étude actuelle a évalué l'efficacité du DriveSharp dans la formation des conducteurs âgés dans un cadre de classe réaliste. Les participants (n = 24) ont assisté à 10 heures de cours de DriveSharp pendant 5 semaines. Les séances pré- et post-test ont evalués améliorations sur un essai dynamique de la perception du risque, Trails A et Trails B. Un groupe de contrôle (n = 18) a terminé seulement les séances pré- et post-test. En classe, les temps de formation étaient plus bas que prévus. L'amélioration des participants aux jeux ont stabilisée après la première évaluation, et le groupe de DriveSharp n'a pas démontré une amélioration significative des performances sur les tests, par rapport au groupe de contrôle. Parmi plusieurs questions relatives à la facilité d'utilisation, les plus problématiques étaient le malentendudes objectifs de la tâche et la différence entre la formation et l'évaluation. Il y a plusieurs implications pour ceux qui utilisent DriveSharp pour améliorer la sécurité des conducteurs âgés.

  5. On sharp estimates of the convergence of double Fourier-Bessel series

    Abilov, V. A.; Abilova, F. V.; Kerimov, M. K.

    2017-11-01

    The problem of approximation of a differentiable function of two variables by partial sums of a double Fourier-Bessel series is considered. Sharp estimates of the rate of convergence of the double Fourier-Bessel series on the class of differentiable functions of two variables characterized by a generalized modulus of continuity are obtained. The proofs of four theorems on this issue, which can be directly applied to solving particular problems of mathematical physics, approximation theory, etc., are presented.

  6. Purchasing Power Parity in Transition Countries: Panel Stationary Test with Smooth and Sharp Breaks

    Mohsen Bahmani-Oskooee

    2015-05-01

    Full Text Available This study examines whether the long-run purchasing power parity (PPP holds in transition economies (Bulgaria, the Czech Republic, Hungary, Latvia, Lithuania, Poland, Romania and Russia using monthly data over the 1995–2011 period. We apply a recently introduced panel stationary test, which accounts for sharp breaks and smooth shifts. The results indicate that the PPP holds only in two countries (i.e., Lithuania and Poland.

  7. Sharp transition between thermal and quantum tunneling regimes in magnetization relaxation processes

    Tejada, J.; Zhang, X. X.; Barbara, B.

    1993-03-01

    In this paper we describe experiments involving measurements of the dependence on time of the thermoremanence magnetization of 2-dimensional random magnets. The low temperature values for the magnetic viscosity agree well with both current theories of tunneling of the magnetization vector (Chudnovsky et al.) and the work of Grabert et al. who predicted that the transition from classical to quantum regime is rather sharp for undamped systems.

  8. Portfolio Optimization under Local-Stochastic Volatility: Coefficient Taylor Series Approximations & Implied Sharpe Ratio

    Lorig, Matthew; Sircar, Ronnie

    2015-01-01

    We study the finite horizon Merton portfolio optimization problem in a general local-stochastic volatility setting. Using model coefficient expansion techniques, we derive approximations for the both the value function and the optimal investment strategy. We also analyze the `implied Sharpe ratio' and derive a series approximation for this quantity. The zeroth-order approximation of the value function and optimal investment strategy correspond to those obtained by Merton (1969) when the risky...

  9. Notes on breeding sharp-shinned hawks and Cooper’s hawks in Barnwell County, South Carolina.

    Vukovich, Mark; Kilgo, John, C.

    2009-07-01

    Abstract - Breeding records of Accipiter striatus (Sharp-shinned Hawks) in the southeastern US are scattered and isolated. We documented a Sharp-shinned Hawk and Accipiter cooperii (Cooper’s Hawk) nest while conducting a telemetry study on Melanerpes erythrocephalus (Red-headed Woodpeckers) in Barnwell County, SC in 2006 and 2007. We report the first known nest of a Sharp-shinned Hawk in Barnwell County, SC and the first report of Sharp-shinned Hawks preying upon Red-headed Woodpeckers. Thirteen of 93 (13.9 %) woodpeckers were killed by accipiters in the summers of 2006 and 2007. Large, contiguous forests managed for Picoides borealis (Red-cockaded Woodpeckers) may be used by breeding Sharp-shinned Hawks. The bright plumage, loud calls, and behavior of Red-headed Woodpeckers, particularly during the nestling stage, may make them conspicuous prey for accipiters.

  10. Adaptive moving mesh methods for simulating one-dimensional groundwater problems with sharp moving fronts

    Huang, W.; Zheng, Lingyun; Zhan, X.

    2002-01-01

    Accurate modelling of groundwater flow and transport with sharp moving fronts often involves high computational cost, when a fixed/uniform mesh is used. In this paper, we investigate the modelling of groundwater problems using a particular adaptive mesh method called the moving mesh partial differential equation approach. With this approach, the mesh is dynamically relocated through a partial differential equation to capture the evolving sharp fronts with a relatively small number of grid points. The mesh movement and physical system modelling are realized by solving the mesh movement and physical partial differential equations alternately. The method is applied to the modelling of a range of groundwater problems, including advection dominated chemical transport and reaction, non-linear infiltration in soil, and the coupling of density dependent flow and transport. Numerical results demonstrate that sharp moving fronts can be accurately and efficiently captured by the moving mesh approach. Also addressed are important implementation strategies, e.g. the construction of the monitor function based on the interpolation error, control of mesh concentration, and two-layer mesh movement. Copyright ?? 2002 John Wiley and Sons, Ltd.

  11. Adjusted Empirical Likelihood Method in the Presence of Nuisance Parameters with Application to the Sharpe Ratio

    Yuejiao Fu

    2018-04-01

    Full Text Available The Sharpe ratio is a widely used risk-adjusted performance measurement in economics and finance. Most of the known statistical inferential methods devoted to the Sharpe ratio are based on the assumption that the data are normally distributed. In this article, without making any distributional assumption on the data, we develop the adjusted empirical likelihood method to obtain inference for a parameter of interest in the presence of nuisance parameters. We show that the log adjusted empirical likelihood ratio statistic is asymptotically distributed as the chi-square distribution. The proposed method is applied to obtain inference for the Sharpe ratio. Simulation results illustrate that the proposed method is comparable to Jobson and Korkie’s method (1981 and outperforms the empirical likelihood method when the data are from a symmetric distribution. In addition, when the data are from a skewed distribution, the proposed method significantly outperforms all other existing methods. A real-data example is analyzed to exemplify the application of the proposed method.

  12. Study of microstructure and fracture properties of blunt notched and sharp cracked high density polyethylene specimens.

    Pan, Huanyu; Devasahayam, Sheila; Bandyopadhyay, Sri

    2017-07-21

    This paper examines the effect of a broad range of crosshead speed (0.05 to 100 mm/min) and a small range of temperature (25 °C and 45 °C) on the failure behaviour of high density polyethylene (HDPE) specimens containing a) standard size blunt notch and b) standard size blunt notch plus small sharp crack - all tested in air. It was observed that the yield stress properties showed linear increase with the natural logarithm of strain rate. The stress intensity factors under blunt notch and sharp crack conditions also increased linearly with natural logarithm of the crosshead speed. The results indicate that in the practical temperature range of 25 °C and 45 °C under normal atmosphere and increasing strain rates, HDPE specimens with both blunt notches and sharp cracks possess superior fracture properties. SEM microstructure studies of fracture surfaces showed craze initiation mechanisms at lower strain rate, whilst at higher strain rates there is evidence of dimple patterns absorbing the strain energy and creating plastic deformation. The stress intensity factor and the yield strength were higher at 25 °C compared to those at 45 °C.

  13. Lithium implantation at low temperature in silicon for sharp buried amorphous layer formation and defect engineering

    Oliviero, E.; David, M. L.; Beaufort, M. F.; Barbot, J. F.; Fichtner, P. F. P.

    2013-01-01

    The crystalline-to-amorphous transformation induced by lithium ion implantation at low temperature has been investigated. The resulting damage structure and its thermal evolution have been studied by a combination of Rutherford backscattering spectroscopy channelling (RBS/C) and cross sectional transmission electron microscopy (XTEM). Lithium low-fluence implantation at liquid nitrogen temperature is shown to produce a three layers structure: an amorphous layer surrounded by two highly damaged layers. A thermal treatment at 400 °C leads to the formation of a sharp amorphous/crystalline interfacial transition and defect annihilation of the front heavily damaged layer. After 600 °C annealing, complete recrystallization takes place and no extended defects are left. Anomalous recrystallization rate is observed with different motion velocities of the a/c interfaces and is ascribed to lithium acting as a surfactant. Moreover, the sharp buried amorphous layer is shown to be an efficient sink for interstitials impeding interstitial supersaturation and {311} defect formation in case of subsequent neon implantation. This study shows that lithium implantation at liquid nitrogen temperature can be suitable to form a sharp buried amorphous layer with a well-defined crystalline front layer, thus having potential applications for defects engineering in the improvement of post-implantation layers quality and for shallow junction formation.

  14. Towards a sharp-interface volume-of-fluid methodology for modeling evaporation

    Pathak, Ashish; Raessi, Mehdi

    2017-11-01

    In modeling evaporation, the diffuse-interface (one-domain) formulation yields inaccurate results. Recent efforts approaching the problem via a sharp-interface (two-domain) formulation have shown significant improvements. The reasons behind their better performance are discussed in the present work. All available sharp-interface methods, however, exclusively employ the level-set. In the present work, we develop a sharp-interface evaporation model in a volume-of-fluid (VOF) framework in order to leverage its mass-conserving property as well as its ability to handle large topographical changes. We start with a critical review of the assumptions underlying the mathematical equations governing evaporation. For example, it is shown that the assumption of incompressibility can only be applied in special circumstances. The famous D2 law used for benchmarking is valid exclusively to steady-state test problems. Transient is present over significant lifetime of a micron-size droplet. Therefore, a 1D spherical fully transient model is developed to provide a benchmark transient solution. Finally, a 3D Cartesian Navier-Stokes evaporation solver is developed. Some preliminary validation test-cases are presented for static and moving drop evaporation. This material is based upon work supported by the Department of Energy, Office of Energy Efficiency and Renewable Energy and the Department of Defense, Tank and Automotive Research, Development, and Engineering Center, under Award Number DEEE0007292.

  15. Numerical investigation of rarefaction effects in the vicinity of a sharp leading edge

    Pan, Shaowu; Gao, Zhenxun; Lee, Chunhian

    2014-12-01

    This paper presents a study of rarefaction effect on hypersonic flow over a sharp leading edge. Both continuum approach and kinetic method: a widely spread commercial Computational Fluid Dynamics-Navior-Stokes-Fourier (CFD-NSF) software - Fluent together with a direct simulation Monte Carlo (DSMC) code developed by the authors are employed for simulation of transition regime with Knudsen number ranging from 0.005 to 0.2. It is found that Fluent can predict the wall fluxes in the case of hypersonic argon flow over the sharp leading edge for the lowest Kn case (Kn = 0.005) in current paper while for other cases it also has a good agreement with DSMC except at the location near the sharp leading edge. Among all of the wall fluxes, it is found that coefficient of pressure is the most sensitive to rarefaction while heat transfer is the least one. A parameter based on translational nonequilibrium and a cut-off value of 0.34 is proposed for continuum breakdown in this paper. The structure of entropy and velocity profile in boundary layer is analyzed. Also, it is found that the ratio of heat transfer coefficient to skin friction coefficient remains uniform along the surface for the four cases in this paper.

  16. SHARP, a first step towards a full sized Jules Verne Launcher

    Bertolini, L.R.; Hunter, J.W. [Lawrence Livermore National Lab., CA (United States); Powell, J.R. [Brookhaven National Lab., Upton, NY (United States); Tidman, D.A. [GT-Devices, Inc., Alexandria, VA (United States)

    1993-05-01

    A vital element for space exploration and utilization is the ability to affordably place large quantities of consumables and building material into low earth orbit. Calculations and supportive data indicate this can be done with a large hydrogen gas gun referred to as the Jules Verne Launcher (JVL). We present a design for the JVL based upon the concept of side injecting preheated hydrogen along a long barrel. This dramatically reduces the peak pressures in the launcher as well as the pressures and g-loads at the vehicle. The JVL has the promise of reducing payload delivery costs to Low Earth Orbit (LEO) to below $500/kg. The Super High Altitude Research Project (SHARP) is a conventional two-stage hydrogen gas gun which is configured to launch 5 kg packages on suborbital trajectories. It is the first step towards the much larger Jules Verne system and will demonstrate several important features of the larger system. SHARP is currently in the middle of a series of tests aimed at its first milestone. This is to launch 5 kg at 4 km/sec horizontally. In its inclined configuration SHARP should launch vehicles to apogees in excess of 400 km and ranges in excess of 700 km.

  17. Development of a Silicon Microneedle with Three-Dimensional Sharp Tip by Electrochemical Etching

    Izumi, Hayato; Okamoto, Tokusuke; Suzuki, Masato; Aoyagi, Seiji

    Aiming at the use in low-invasive medical treatments, this paper reports a fabrication technique of silicon microneedle of conical sharp point. The electrochemical etching technique is employed for sharpening the tip of a pillar, which is diced from a silicon wafer. A finely smooth tip surface is obtained due to electrochemical etching reactions, and is effective for easy insertion. The fabrication method is based on inexpensive wet etching, which does not require expensive fabrication facilities such as deep reactive ion etching (DRIE). A sharp needle was successfully fabricated, the tip angle of which was considerably small and was distributed within the range from 15 to 30 deg. An experiment of inserting the fabricated needle into an artificial skin of silicone rubber was carried out. As the results, the resistance force during insertion was much reduced compared to those of two-dimensional sharp needles. Imitating mosquito's motion, the effectiveness of applying vibration to the fabricated needle during insertion was also confirmed. After biocompatible Parylene coating, puncturing a human skin was demonstrated assuming a lancet usage for the diabetics, in which the bleeding was surely observed.

  18. Vatellini Sharp (Coleoptera, Dytiscidae) from Brazil: two new species, new records, and a checklist.

    Braga, Rafael Benzi; Ferreira, Nelson

    2016-05-12

    The tribe Vatellini Sharp, 1882 is composed of 55 species divided in two genera. Even though a recent revision of the tribe was made, Vatellini of the new world are weakly explored with great gaps in the distributions of species. In Brazil the knowledge is based only on a few localities. In this work two new species are described and illustrated, Vatellus caissara sp. nov. and Vatellus yanomami sp. nov.; new records are given for Brazil: Vatellus maculosus Miller, 2005 in the state of Mato Grosso, Derovatellus lentus (Wehncke, 1876) in Amazonas, Pará and Rio de Janeiro, Vatellus lateralis (Sharp, 1882) in Alagoas, Ceará, Espírito Santo, Pará, Pernambuco and Rio Grande do Sul, Vatellus sahlbergi (Sharp, 1882) in Rio de Janeiro, and Vatellus tarsatus (Laporte, 1835) in Pará. A checklist with all species of Vatellini occurring in Brazil is provided and steps for identification of the new species are added in the key of Miller (2005).

  19. The Influence of the Sharpe Ratio on Appreciation Savings Intended for the Payment of Lifetime Pensions

    Petr Kupčík

    2015-01-01

    Full Text Available The paper focuses on the payment of lifetime pensions paid by pension companies based on the selected mortality table of the Czech Statistical Office. We assume different input values depending on the size of the Sharpe ratio pension companies from selected countries. This paper aims to identify and assess the impact of the Sharpe ratio on the payment of lifetime pensions in postproduction period. We used data of nominal appreciation of pension companies from the Visegrad countries and Sweden, Switzerland and the Netherlands in the period 2005–2013. In the empirical analysis we additionally distinguished between guaranteed and non-guaranteed pension funds. For the purpose of calculating lifetime pensions, we used the formula early paid pension by the pension company on the Czech market down in its her pension plan with an expected median payment period of r years. We found link between the value of the Sharpe ratio and the size of lifetime pensions. Conclusion of the paper shows the effects of low performance of pension funds on lifetime pension with a focus on the Czech Republic. The scientific paper describes partial results reached within the project no. 54/2014 of the Internal Grant Agency of the Faculty of Business and Economics of the Mendel University in Brno following the aims and methodology of the given project.

  20. Assessment of myocardial viability by MR imaging

    Sandstede, Joern J.W.

    2003-01-01

    Diagnosis of myocardial viability after infarction focuses on the prediction of functional improvement of dysfunctional myocardium after revascularization therapy. Magnetic resonance imaging provides different approaches for the detection of myocardial viability. Measurement of end-diastolic wall thickness is easy to perform and has a high sensitivity, but a low specificity, and can only be used 4 months after myocardial infarction due to infarct healing processes. Low-dose dobutamine stress has a good sensitivity with a high specificity for the prediction of wall motion improvement, but this is only true for patients with a singular dysfunctional area and only slightly depressed cardiac function. Late enhancement allows for direct visualization of necrotic or scarred tissue. By measuring the transmural extent of late enhancement, the probability of mechanical improvement can precisely be given. Imaging of microvascular obstruction by first-pass perfusion or late enhancement gives additional information on viability and patient prognosis. Metabolic imaging techniques, such as 31 P-MR spectroscopy and 23 Na-MR imaging, provide further insights into the mechanisms of myocardial infarction and viability. In conclusion, cardiac MRI offers several clinically usable approaches for the assessment of myocardial viability and will probably become the method of choice in the near future. (orig.)

  1. Stress myocardial scintigraphy in coronary artery disease

    Hata, Noritake; Koumi, Shin-ichi; Yasutake, Masahiro; Imaizumi, Takahiro; Saito, Tsutomu; Kishida, Hiroshi; Hayakawa, Hirokazu

    1991-01-01

    To evaluate the clinical significance of asymptomatic ischemic heart disease, exercise electrocardiography and stress myocardial scintigraphy were performed. These were correlated with symptoms during exercise tests and histories of myocardial infarction (MI). The study subjects consisted of 70 patients with coronary artery disease, including 34 with MI, and 36 without MI but with angina pectoris. Stress tests were performed using bicycle ergometer under electrocardiographic monitoring throughout the test. Transient myocardial ischemia was confirmed by perfusion defects on thallium myocardial imaging demonstrated immediately after exercise, but not 3 hours after the stress test. Asymptomatic ST depression was observed in 18 of 34 patients with MI (53%) and in 21 of the 36 patients with angina (58%); however, transient myocardial perfusion defects were confimred in 61% of the patients with MI (11 of 18 patients), but in only 33% of those with angina (7 of 21 patients). The difference was statistically significant (p<0.05). It was suggested that there are some differences in the clinical significance of asymptomatic ST depression between the patients with MI and those without MI but with angina pectoris. (author)

  2. Meta-Analysis of Stress Myocardial Perfusion Imaging

    2017-06-06

    Coronary Disease; Echocardiography; Fractional Flow Reserve, Myocardial; Hemodynamics; Humans; Magnetic Resonance Imaging; Myocardial Perfusion Imaging; Perfusion; Predictive Value of Tests; Single Photon Emission Computed Tomography; Positron Emission Tomography; Multidetector Computed Tomography; Echocardiography, Stress; Coronary Angiography

  3. Association of blood transfusion with increased mortality in myocardial infarction

    Chatterjee, Saurav; Wetterslev, Jørn; Sharma, Abhishek

    2013-01-01

    The benefit of blood transfusion in patients with myocardial infarction is controversial, and a possibility of harm exists.......The benefit of blood transfusion in patients with myocardial infarction is controversial, and a possibility of harm exists....

  4. Aircraft noise, air pollution, and mortality from myocardial infarction.

    Huss, A.; Spoerri, A.; Egger, M.; Roosli, M.

    2010-01-01

    OBJECTIVE: Myocardial infarction has been associated with both transportation noise and air pollution. We examined residential exposure to aircraft noise and mortality from myocardial infarction, taking air pollution into account. METHODS: We analyzed the Swiss National Cohort, which includes

  5. Association between intraoperative hypotension and myocardial injury after vascular surgery

    van Waes, JAR; Van Klei, Wilton A.; Wijeysundera, Duminda N.; Van Wolfswinkel, Leo; Lindsay, Thomas F.; Beattie, W. Scott

    2016-01-01

    Background: Postoperative myocardial injury occurs frequently after noncardiac surgery and is strongly associated with mortality. Intraoperative hypotension (IOH) is hypothesized to be a possible cause. The aim of this study was to determine the association between IOH and postoperative myocardial

  6. Usefulness of rest-redistribution on thallium myocardial scintigraphy in patients with acute myocardial infarction by SPECT; Analysis by bull's eye and unfolded map images

    Tahara, Yorio; Taya, Makoto; Sasaki, Akira; Nishimura, Tooru; Shimoyama, Katsuya; Mizuno, Haruyoshi; Ono, Akifumi; Okada, Michio; Ishikawa, Kyozo (Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine)

    1990-01-01

    The purpose of this study was to clarify the clinical significance of rest-redistribution in myocardial scintigraphy (SPECT) in acute myocardial infarction (AMI). 30 patients with AMI within one week after the onset of attack were studied. SPECT images were obtained 10 min and 3hrs after injection of {sup 201}Tl. Bull's eye images and unfolded map images were prepared. A {sup 201}Tl uptake was studied at the infarct and non-infarct sites. Exercise SPECT and radionuclide angiography were performed in all patients one month after the onset of AMI, and the findings were compared with clinical and coronary angiographic (CAG) findings. Redistribution of Tl at rest was observed at the infarct sites in 9 of the 30 patients. Redistribution at rest was observed at the non-infarct sites in 8 patients. Redistribution at rest was observed during exercise SPECT one month after the onset of AMI in patients with redistribution at rest in the acute phase. In patients with redistribution at rest at the infarct site, left ventricular ejection fraction (EF) improved one month after the onset of AMI ({Delta}EF>5%), but it decreased slightly during exercise. Wall motion at the infarct site was not much impaired in patients who showed redistribution at rest at the infarct site. Angina pectoris and recurrence of myocardial infarction were observed more frequently on SPECT, but no characteristic findings were obtained on CAG in those with redistribution at rest. In conclusion, cardiac function and wall motion at the infarct site are better preserved in patients with redistribution of Tl at rest on SPECT in the acute stage of myocardial infarction, as compared with patients having fixed defects, but the EF decrease slightly during exercise and the frequency of post-infarction angina is greater in those patients. Resting SPECT in AMI is considered to provide useful information for predicting cardiac function and the clinical course following myocardial infarction. (author).

  7. [Reduction of in-hospital mortality and improved secondary prevention after acute myocardial infarction. First results from the registry of secondary prevention after acute myocardial infarction (SAMI)].

    Tebbe, U; Messer, C; Stammwitz, E; The, G S; Dietl, J; Bischoff, K-O; Schulten-Baumer, U; Tebbenjohanns, J; Gohlke, H; Bramlage, P

    2007-07-30

    In hospital mortality of acute myocardial infarction (AMI) has been reduced due to the availability of better therapeutic strategies. But there is still a gap between mortality rates in randomised trials and daily clinical practice. Thus, it was aim of the present registry to document the course and outcome of patients with AMI and to improve patient care by implementing recent guidelines. In a nationwide registry study in hospitals in Germany with a cardiology unit or an internal medicine department data on consecutive patients were recorded for six to twelve months at admission, discharge and during a follow-up of one year. From 02/2003 until 10/2004 a total of 5,353 patients with acute myocardial infarction (65.7 % male, mean age of 67.6 +/- 17.7 years; 55.1 % of them with ST elevation myocardial infarction (STEMI) were included in the registry. Of the patients with STEMI, 76.6 % underwent acute intervention, 37.1 % had thrombolysis, 69.7 % percutaneous transluminal coronary angioplasty (PTCA). 40.0 % of those with non-Stemi (NSTEMI) had an acute intervention, 6.6 % thrombolysis, 73.5 % PTCA. Recommended secondary prevention consisted of ASS (93.2 %), beta-blockers (93.0 %), CSE-inhibitors (83.5 %), ACE-inhibitors (80.9 %) and clopidogrel (74.0 %). In-hospital mortality was 10.5 % (STEMI) and 7.4 % (NSTEMI). The 9 % mortality among patients with acute myocardial infarction treated in the hospitals participating in the SAMI registry is low compared to that in similar collectives. The high number of patients who had thrombofibrinolysis and coronary interventions as well as the early initiation of drug therapy contributed to these results. Medical treatment in the prehospital phase of these patients remains still insufficient and to a substantial extent contributes to the mortality of acute myocardial infarction.

  8. Myocardial dysfunction in malnourished children

    Faddan Nagla Hassan

    2010-01-01

    Full Text Available Background : Malnourished children suffer several alterations in body composition that could produce cardiac abnormalities. Aim : The aim of the present study was to detect the frequency of myocardial damage in malnourished children as shown by echocardiography and cardiac troponin T (cTnT level. Methods : Forty-five malnourished infants and young children (mean±SD of age was 11.24 ±7.88 months were matched with 25 apparently healthy controls (mean±SD of age was 10.78±6.29 months. Blood sample was taken for complete blood picture, liver and kidney function tests, serum sodium, potassium, calcium levels and cTnT. All the malnourished children were subjected to echocardiographic evaluation. Results : Malnourished children showed a significantly lower left ventricular (LV mass than the control group. The LV systolic functions were significantly impaired in patients with severe malnutrition. The cTnT level was higher than the upper reference limits in 11 (24.44% of the studied malnourished children and all of them had a severe degree of malnutrition. The cTnT level was significantly higher in patients with anemia, sepsis and electrolyte abnormalities and it correlated negatively with LV ejection fraction (EF. Six of the studied children with high cTnT levels (54.5% died within 21 days of treatment while only one case (2.9% with normal level of cTnT died within the same period. Conclusions: LV mass is reduced in malnourished children. Children with severe malnutrition have a significant decrease in LV systolic functions. Elevated cTnT levels in malnourished children has both diagnostic and prognostic significance for cardiomyocyte damage.

  9. Delayed ventricular septal rupture complicating acute inferior wall myocardial infarction

    Cho, Jae Hyung; Sattiraju, Srinivasan; Mehta, Sanjay; Missov, Emil

    2013-01-01

    Background Ventricular septal rupture is a potentially fatal complication of acute myocardial infarction. Its incidence has declined with modern reperfusion therapy. In the era of percutaneous coronary interventions, it occurs a median of 18?24?hours after myocardial infarction and is most commonly associated with anterior myocardial infarction. We present a case of delayed ventricular septal rupture complicating acute inferior wall myocardial infarction. Case presentation A 53-year-old Cauca...

  10. Rationale and radiopharmaceuticals for myocardial imaging

    Poe, N.D.

    1976-01-01

    Static radionuclide imaging procedures are now available for evaluating regional myocardial perfusion and for detecting acute myocardial infarction. Thallium-201, a radiopharmaceutical which possesses many of the characteristics of potassium analogs, at present is receiving the greatest attention as a regional blood flow indicator. Ischemic lesions appear as areas of decreased tracer uptake. Unfortunately, this agent is expensive, is in limited supply and has a photopeak which is low for optimum imaging. Positive infarct images can be obtained with various technetium-99m chelates. Pyrophosphate appears to be the best of the technetium compounds studied to date although the mechanism of uptake of the chelates has not yet been fully elucidated. Therefore, quantitative measurements of infarct size are not justified. As perfusion imaging and infarct imaging provide useful, complementary data, a dual tracer approach to evaluating patients with suspected coronary artery disease and/or myocardial infarction is probably justifiable

  11. Perfusion scintigraphy in acute myocardial infarction

    Schricke, U.; Schwaiger, M.; Kastrati, A.; Schoemig, A.

    1999-01-01

    The Tc-99m sestamibi perfusion SPECT scintigraphy in acute myocardial infarction is a feasible method to assess the size of area at risk and the residual blood flow to this area as the most important determinants of final infarct size without any delay in treatment. In combination with a follow-up study final infarct size as well as myocardial salvage can be quantified. Clinical indications for the use of Tc-99m sestamibi scintigraphy are the noninvasive identification of arterial occlusion in patients suspected to acute myocardial infarction without electrocardiographic ST-elevation and the assessment of reperfusion success. In clinical trials Tc-99m sestamibi scintigraphy has proven to be a useful method to assess the impact of varying reperfusion therapies. The present review article discusses the indication, the study protocol, the interpretation of results and the clinical and scientifically importance of this method. (orig.) [de

  12. Alcohol and the risk of myocardial infarction.

    Flesch, M; Rosenkranz, S; Erdmann, E; Böhm, M

    2001-04-01

    Epidemiological studies have repeatedly demonstrated a beneficial effect of moderate alcohol consumption on the incidence of coronary heart disease, myocardial infarction and overall mortality. The latter increases with excessive alcohol consumption. Although most epidemiological studies demonstrate a beneficial effect of alcohol consumption independent from the specific kind of alcoholic beverage, there is increasing evidence that wine and in particular red wine might contain pharmacological substances, which prevent atherosclerosis and myocardial infarction independent from the wine ethanol. Pathophysiological mechanisms mediating these beneficial effects include effects of wine phenols and tannins on LDL-cholesterol oxidation status, thrombocyte aggregation, endothelial function and smooth muscle cell proliferation. Identification and characterization of the pharmacologically active substances might provide the stage for the development of new substances to be used in the prevention of coronary artery disease and myocardial infarction.

  13. Acute myocardial infarction in a young patient

    Hameed, A.; Ata-ur-Rehman Quraishi

    2004-01-01

    Myocardial infarction (MI) is considered to be the disease of the fifth and sixth decade as seen in the West but an earlier age incidence is not infrequently encountered in the South Asian population. However, occurrence of MI in the teen-age still remains a rare happening. We are reporting a case of a teenager, who suffered a myocardial infarction with cardiogenic shock and pulmonary edema on two separate occasions with ECG and biochemical evidence of myocardial infarction. An exercise stress test done in between the two episodes was negative at a workload of 13.5 METs. A coronary angiogram done after the second event revealed normal coronary arteries and a preserved left ventricular systolic and segmental function. Except for low HDL (high density lipoprotein) and mildly raised homocysteine levels, the patient did not have other conventional or novel risk factors for coronary artery disease. (author)

  14. The Myocardial Performance Index During Low Dose Dobutamine Echocardiography in Normals and Patients With a Recent Myocardial Infarction

    Nørager, Betina; Husic, Mirza; Møller, Jacob E

    2004-01-01

    BACKGROUND: Wall-motion analysis during low-dose dobutamine echocardiography (LDDE) is a semiquantitative measure of left ventricular contractile reserve after myocardial infarction (MI). The Doppler echocardiographic myocardial performance index (MPI) is a quantitative measure of combined left...

  15. Analysis of the cardiac motion in myocardial infarction by the ECG-synchronized CT

    Watanabe, Shigeru; Shimizu, Masahiko; Yoshida, Hideo; Morooka, Nobuhiro; Shukuya, Masaki

    1981-01-01

    The cardiac motion in patients with myocardial infarction was analyzed by the ECG-synchronized computed tomography (CT). For ECG synchronization, the ECG gating method and the data sorting method were used. By the ECG gating method, the gated cardiac images during 0.1 msec intervals at end-diastolic and the end-systolic phases were obtained. By the data sorting method, phasic CT images were reconstructed retrospectively by selecting appropriate data from a series of consecutive scans taken with simultaneous continuous ECG recordings. Six normal subjects and eight patients with myocardial infarction were studied by the ECG gating method, and 14 normal subjects and 25 patients with myocardial infarction were studied by the data sorting method. The end-diastolic and the end-systolic pictures at mid left ventricular level were superimposed and the cardiac borders were traced for the analysis (Fig. 4). Then the cardiac cross-sectional areas at each cardiac phase (40 msec) were calculated, and a cardiac area curve was obtained by plotting them consecutively. The cross-sectional images were divided into right anterior, right posterior, left anterior and left posterior segments. Cardiac area curves of the each segment were also obtained for further analysis. From these curves, the changing ratio of cardiac areas (maximum area - minimum area/maximum area) and the maximum area velocity in systole and diastole were calculated. On the images and the cardiac area curves in myocardial infarction patients, abnormal myocardial movements such as partial akinesis, hypokinesis or paradoxical movement were apparent asd the area of abnormal motions corresponded well with the location of infarction determined by ECG, RI scanning and angiography. A decrease of the changing ratio and the velocity in the infarction area were shown (Fig. 6, 7) and the functional disturbances were suggested during not only systole but diastole also. (author)

  16. Assessment of myocardial viability by exercise stress myocardial tomography with 201Tl

    Narita, Michihiro; Kurihara, Tadashi; Murano, Kenichi; Usami, Masahisa

    1992-01-01

    Exercise stress (Ex) and redistribution (RD) myocardial tomography with Tl-201 has been widely used for evaluating myocardial viability. But recent studies have demonstrated that reinjection (ReI) study following RD study is necessary for detecting reversible ischemic myocardium. On the other hand, decreased myocardial washout of Tl-201 after Ex is an indicator of myocardial ischemia. So we have studied the usefulness of myocardial Tl-201 washout rate (WOR) for the evaluation of myocardial viability by comparing it with ReI images. Ex and RD myocardial tomographies were obtained immediately after Ex and 3 hours later. After RD study a small amount of Tl-201 was injected and ReI imaging was repeated. We studied 64 myocardial segments (in 58 patients with coronary artery disease) in which Ex-induced perfusion defects persisted in RD images. According to the changes of perfusion defects between Ex, RD and ReI images, they were classified into 3 types: Type I; perfusion defect on the RD image was identical to ReI image (75%). Type I was divided into 2 subgroups whether perfusion defect at Ex was unchanged (Ia, 42%) or improved (Ib, 33%) on the RD image. Type II; perfusion defect at Ex was reduced on the RD image and it improved furthermore at ReI image (17%). Type III; perfusion defect was the same at Ex and RD but it was reduced on the ReI image (8%). WOR less than 30% was defined as abnormal when Ex heart rate exceeded 120 bpm and lung-myocardial Tl-201 uptake ratio was less than 0.45. The differentiation between Type Ia and Type III is of great importance. History of myocardial infarction, effort angina and Ex induced ST depression could not differentiate these 2 groups. WOR abnormality was observed in all of Type III, but WOR was normal in Type Ia. In conclusion, WOR abnormality in Ex-RD myocardial imaging is useful for evaluating myocardial viability. ReI imaging is necessary for the precise evaluation of viable muscle mass and for inadequate Ex. (author)

  17. Asymptomatic myocardial ischemia following cold provocation

    Shea, M.J.; Deanfield, J.E.; deLandsheere, C.M.; Wilson, R.A.; Kensett, M.; Selwyn, A.P.

    1987-01-01

    Cold is thought to provoke angina in patients with coronary disease either by an increase in myocardial demand or an increase in coronary vascular resistance. We investigated and compared the effects of cold pressor stimulation and symptom-limited supine bicycle exercise on regional myocardial perfusion in 35 patients with stable angina and coronary disease and in 10 normal subjects. Regional myocardial perfusion was assessed with positron emission tomography and rubidium-82. Following cold pressor stimulation 24 of 35 patients demonstrated significant abnormalities of regional myocardial perfusion with reduced cation uptake in affected regions of myocardium: 52 +/- 9 to 43 +/- 9 (p less than 0.001 vs normal subjects). Among these 24 patients only nine developed ST depression and only seven had angina. In contrast, 29 of 35 patients underwent supine exercise, and abnormal regional myocardial perfusion occurred in all 29, with a reduction in cation intake from 48 +/- 10 to 43 +/- 14 (p less than 0.001 vs normal subjects). Angina was present in 27 of 29 and ST depression in 25 of 29. Although the absolute decrease in cation uptake was somewhat greater following cold as opposed to exercise, the peak heart rate after cold was significantly lower than that after exercise (82 +/- 12 vs 108 +/- 16 bpm, p less than 0.05). Peak systolic blood pressures after cold and exercise were similar (159 +/- 24 vs 158 +/- 28). Thus, cold produces much more frequent asymptomatic disturbances of regional myocardial perfusion in patients with stable angina and coronary disease than is suggested by pain or ECG changes

  18. Symbolic reasoning about myocardial scintigrams in PROLOG

    Rosenberg, S.; Itti, R.; Benjelloun, L.

    1986-01-01

    PROLOG (PROgramming in LOGic) is the declarative programming language at the heart of the Japanese fifth-generation computer project. It is proposed that PROLOG is a suitable tool for symbolic image processing, once standard preprocessing has been done. In the present application, the problem of prediction of coronary anatomy from myocardial scintigrams is addressed. Uncertainty is dealt with by a combination of fuzzy-set theoretic and probabilistic reasoning. Heuristic classification rules are based on clinical experience and on a set of 247 myocardial scintigrams with their corresponding coronary angiograms. (orig.)

  19. Scintigraphic demonstration of acute myocardial infarcts

    Holman, B.L.; Lesch, M.

    1976-01-01

    The feasibility of acute infarct scintigraphy for the clinical evaluation of patients with known or suspected acute myocardial infarction is established. Further development of this methodologic approach may result in even better agents for the visualization of infarcts. Radiotracers with high affinity for the infarct, rapid blood clearance, and low concentrations in surrounding organs, such as liver and bone, would be more suitable than available radiopharmaceuticals for acute myocardial infarct scintigraphy. Ultimately, labeling these tracers and ultra-short-lived radionuclides will enable rapid sequential imaging to assess changes in the extent of infarction and to determine the efficacy of therapies aimed at limiting infarct size

  20. Proton chemical shift imaging after myocardial infarction

    Bouchard, A.; Doyle, M.; Pohost, G.M.

    1989-01-01

    The present study was undertaken to test whether chemical shift imaging could detect spatially the lipids known to accumulate in myocardium after an ischemic insult. Seven dogs underwent a 24-hour coronary artery occlusion. Hearts were removed and imaged ex vivo by the Dixon method (1.5 T), and myocardial samples were obtained for high-resolution H-1 spectroscopy. Lipid images revealed regions of increased signal intensity in the periphery f the myocardial infarction. The zones of high lipid signal corresponded to zones with elevated mobile lipids as detected by H-1 spectroscopy

  1. Myocardial Na,K-ATPase: Clinical aspects

    Kjeldsen, Keld

    2003-01-01

    The specific binding of digitalis glycosides to Na,K-ATPase is used as a tool for Na,K-ATPase quantification with high accuracy and precision. In myocardial biopsies from patients with heart failure, total Na,K-ATPase concentration is decreased by around 40%; a correlation exists between a decrease in heart function and a decrease in Na,K-ATPase concentration. During digitalization, around 30% of remaining pumps are occupied by digoxin. Myocardial Na,K-ATPase is also influenced by other drugs...

  2. Symbolic reasoning about myocardial scintigrams in PROLOG

    Rosenberg, S; Itti, R; Benjelloun, L

    1986-06-01

    PROLOG (PROgramming in LOGic) is the declarative programming language at the heart of the Japanese fifth-generation computer project. It is proposed that PROLOG is a suitable tool for symbolic image processing, once standard preprocessing has been done. In the present application, the problem of prediction of coronary anatomy from myocardial scintigrams is addressed. Uncertainty is dealt with by a combination of fuzzy-set theoretic and probabilistic reasoning. Heuristic classification rules are based on clinical experience and on a set of 247 myocardial scintigrams with their corresponding coronary angiograms.

  3. Depth and sharpness variations of 410-km and 660-km discontinuities in North China Craton from dense array ambient noise interferometry

    Yao, H.; Feng, J.; Poli, P.; Fang, L.; Wu, Y.

    2017-12-01

    Recent studies have demonstrated that body waves between pairs of stations can be successfully retrieved from ambient noise cross-correlation at both regional and global scales, although surface waves are the dominant signals. However, it is still difficult to use these retrieved body wave signals to map lateral depth variations of main structural discontinuities or velocity contrasts because of its low signal to noise ratio (SNR). In this research, based on a dense seismic array in eastern North China Craton, reflected P-wave signals from 410-km and 660-km discontinuities can be successfully recovered from ambient noise cross-correlation. To improve SNR of the reflected phases, the cross-correlations are stacked within each bin with the phase-weighted stack (PWS) method. In addition, there exist apparent spatial variations of the relative amplitude ratios between the reflected P410P and P660P phases. The retrieved P410P and P660P phases from stacked correlations reveal lateral variations of both depths and sharpness of the 410-km and 660-km discontinuities along two profiles, which may be related with hot material upwelling and the effect of stagnant Pacific plate in the transition zone beneath North China Craton. The imaging results are generally consistent with the results from teleseismic receiver functions, which demonstrate the possibility of mapping high-resolution topography and sharpness of deep internal discontinuities without earthquake-station geometric limitations. Future joint imaging with both interferometric and passive signals will be better for understanding interface architectures and related dynamic processes of the Earth.

  4. Incessant ventricular tachycardia early after acute myocardial infarction: efficacy of radiofrequency catheter ablation but not of optimal coronary revascularization.

    Bonanno, C; Ometto, R; Finocchi, G; Rulfo, F; La Vecchia, L; Vincenzi, M

    1999-12-01

    Incessant ventricular tachycardia is an arrhythmia refractory to conventional antiarrhythmic treatment. We describe the case of 55-year-old man who presented incessant ventricular tachycardia in the early post-acute phase of myocardial infarction. Optimal coronary revascularization was not effective, but radiofrequency catheter ablation was able to eliminate the anatomic substrate and clinical arrhythmic recurrence.

  5. Residual Activity Correction in Quantitative Myocardial Perfusion N-13-Ammonia PET Imaging : A Study in Post-MI Patients

    Markousis-Mavrogenis, George; Juarez-Orozco, Luis Eduardo; Alexanderson, Erick

    2017-01-01

    Background/Introduction/Aim: Positron emission tomography (PET) is the gold standard for the quantification of myocardial blood flow (MBF). A standard PET scan is acquired in two phases (rest and pharmacological stress). N-13-ammonia is a perfusion radiotracer that may show residual activity, which

  6. Positron computed tomography for myocardial uptake of N-13 ammonia in patients with hypertrophic cardiomyopathy

    Yoshida, Katsuya; Himi, Toshiharu; Imai, Hitoshi; Shukuya, Masaki; Masuda, Yoshiaki; Inagaki, Yoshiaki; Yamasaki, Toshiro; Tateno, Yukio.

    1985-01-01

    In the present study, positron computed tomography (PCT) was used to evaluate the myocardial uptake of N-13 ammonia in patients with hypertrophic cardiomyopathy (HCM). Eight subjects including two normal persons, four patients with HCM, and two with old myocardial farction (OMI) were selected for the study. N-13 ammonia was administered intravenously as a bolus and, commencing with the tracer injection, serial 30-second PCT scans were performed. The results were summarized as follows: 1. The first scan exhibiting cardiac blood pool images revealed a reduced left ventricular cavity in the HCM subjects. 2. After clearance of N-13 from the cardiopulmonary vasculature, the left ventricular myocardium was clearly visualized and an increased myocardial mass with characteristic morphology was demonstrated in the HCM subjects. 3. Detailed analysis of the time-activity curves of the blood pool and myocardium derived from these serial scan images disclosed two uptake phases in the uptake mode of N-13 ammonia. In the initial phase within three minutes, the myocardial uptake of N-13 was rapid in the normal and OMI subjects, whereas its significant delay was observed in the HCM subjects. This may reflect an abnormal initial extraction of N-13 ammonia in the HCM patients compared with the other subjects. 4. Subsequently, in the second phase, which was characterized by a gradual increase of N-13 in the myocardium, the HCM subjects revealed higher uptake ratios than did the others. This may indicate an increased extraction of metabolites of N-13 ammonia during the second phase. These preliminary results undersore the usefulness of dynamic PCT with N-13 ammonia for the assessment of HCM. (author)

  7. Gated spect myocardial perfusion scintigraphy for identifying septal perfusion artifacts in left bundle branch block

    Afzal, M.S.; Imran, M.B.; Akhtar, M.S.; Muhammand, K.; Nadeem, A.; Aslam, N.; Khurshid, S.J.; Farooq, U.I.; Sohaib, M.

    2006-01-01

    To determine the role of gated Single Photon Emission Computed Tomography (SPECT) for accurate assessment of myocardial perfusion scintigraphy (MPS) of patients with left bundle branch block (LBBB). MPS data of patients with LBBB was analyzed. Resting gated SPECT MPS was performed after an injection of 740 MBq 99mTc-MIBI in 10 normal and 25 subjects with LBBB (with low probability of coronary artery disease). Visual and quantitative analyses were done on non-gated (NG), end diastolic (ED), end systolic (ES) images. Calculations included septal to lateral wall ratio (SLR), myocardial thickening (MT=% increase in counts during systole) at end systolic phase and myocardial thickening at peak level (% peak MT). Septal hypoperfusion was noted in 19 (76%) patients on NG images and in only 1 (4%) patient on gated SPECT ED images. On NG images of LBBB group, SLR was lower than in controls (0.68 +- 0.07 vs. 0.87 +- 0.05, p<0.001). SLR of LBBB patients approached to that of control group in gated SPECT ED data (0.86 +- 0.06 vs 0.88 +- 0.06, p=ns). Myocardial thickening at ES for septum was markedly lower in LBBB group than in controls (21.83% +- 10.86 vs. 66.32% +- 20.15, p<0.001). (author)

  8. Recent developments in gamma camera technology for myocardial perfusion scintigraphy

    Bengel, Frank M.

    2010-01-01

    Economic pressure, competition from alternative modalities and an increasing awareness of patient radiation exposure have triggered a rapid development of novel technology for cardiac single-photon emission computed tomography (SPECT) in recent years. The trend clearly goes towards systems with higher sensitivity and resolution, and towards faster acquisition protocols. Those goals are achieved by various measures: On the one hand, several manufacturers have integrated novel semiconductor detector materials together with innovative collimators into dedicated cardiac scanners. On the other hand, new collimators and reconstruction algorithms have lead to increased speed and accuracy of conventional gamma cameras. Imaging times now can be reduced to as much as 10% of that of previous standard protocols, and/or injected activity can be reduced. This is achieved without loss of diagnostic accuracy. These novel developments are still in early phases of clinical implementation. Their potential for a profound change of the clinical practice of myocardial perfusion scintigraphy, however, becomes increasingly obvious. (orig.)

  9. Justification for intravenous magnesium therapy in acute myocardial infarction

    Rasmussen, H S

    1988-01-01

    Recent studies have shown that patients with acute myocardial infarction (AMI) are magnesium-deficient and develop an additional transient decrease in serum magnesium concentrations (S-Mg c) during the acute phase of the infarct. Animal experiments, as well as studies on humans, have indicated.......v. magnesium therapy on mortality and incidence of arrhythmias in patients with AMI has been evaluated. Magnesium treatment more than halved the acute mortality and incidence of arrhythmias requiring treatment in three of the four intervention studies. The mechanisms behind the beneficial effect of magnesium...... therapy are probably multifactorial; a direct depressive effect on the cardiac conducting system; a peripheral dilatory effect on the arteries, reducing the afterload on the myocardium; a reduced infarct size; an ion-stabilizing effect, maintaining stable intra and extracellular concentrations...

  10. Stereotactic hypofractionated accurate radiotherapy of the prostate (SHARP), 33.5 Gy in five fractions for localized disease: First clinical trial results

    Madsen, Berit L.; Hsi, R. Alex; Pham, Huong T.; Fowler, Jack F.; Esagui, Laura C.; Corman, John

    2007-01-01

    Purpose: To evaluate the feasibility and toxicity of stereotactic hypofractionated accurate radiotherapy (SHARP) for localized prostate cancer. Methods and Materials: A Phase I/II trial of SHARP performed for localized prostate cancer using 33.5 Gy in 5 fractions, calculated to be biologically equivalent to 78 Gy in 2 Gy fractions (α/β ratio of 1.5 Gy). Noncoplanar conformal fields and daily stereotactic localization of implanted fiducials were used for treatment. Genitourinary (GU) and gastrointestinal (GI) toxicity were evaluated by American Urologic Association (AUA) score and Common Toxicity Criteria (CTC). Prostate-specific antigen (PSA) values and self-reported sexual function were recorded at specified follow-up intervals. Results: The study includes 40 patients. The median follow-up is 41 months (range, 21-60 months). Acute toxicity Grade 1-2 was 48.5% (GU) and 39% (GI); 1 acute Grade 3 GU toxicity. Late Grade 1-2 toxicity was 45% (GU) and 37% (GI). No late Grade 3 or higher toxicity was reported. Twenty-six patients reported potency before therapy; 6 (23%) have developed impotence. Median time to PSA nadir was 18 months with the majority of nadirs less than 1.0 ng/mL. The actuarial 48-month biochemical freedom from relapse is 70% for the American Society for Therapeutic Radiology and Oncology definition and 90% by the alternative nadir + 2 ng/mL failure definition. Conclusions: SHARP for localized prostate cancer is feasible with minimal acute or late toxicity. Dose escalation should be possible

  11. The expression of myocardial injury in cold induced myocardial imaging and echocardiography of systematic scleroderma

    Liang Jiugen; Zhu Xiaojun; Jiang Ningyi; Chen Shaoxiong

    1999-01-01

    The study was performed with cold-induced 99m Tc(MIBI) myocardial imaging (MI) in 23 patients with systematic scleroderma. The left ventricular function and wall motion were also observed by dimensional echocardiography (UCG). 14 patients had myocardial perfusion abnormalities visualized by MI, including 5 cases with fixed defects of 9 segments, 3 cases with reversible defects of 6 segments and 6 cases with both fixed and reversible one of 14 segments. The positive rate in myocardial imaging had no significant differences between patients with and without Raynaud's phenomenon (0.5>P>0.25). Compared with baseline, the ejection fraction, stroke volume, cardiac output were significantly decreased during cold-induced in patients with abnormal myocardial scintigraphy (P<0.05), and had significant difference compared with normal group (P<0.05). 4 cases with cold-induced reversible perfusion defects had anatomically correlated regional ventricular hypokinesia in UCG

  12. The visibility of IQHE at sharp edges: experimental proposals based on interactions and edge electrostatics

    Erkarslan, U; Oylumluoglu, G; Grayson, M; Siddiki, A

    2012-01-01

    The influence of the incompressible strips on the integer quantized Hall effect (IQHE) is investigated, considering a cleaved-edge overgrown (CEO) sample as an experimentally realizable sharp edge system. We propose a set of experiments to clarify the distinction between the large-sample limit when bulk disorder defines the IQHE plateau width and the small-sample limit smaller than the disorder correlation length, when self-consistent edge electrostatics define the IQHE plateau width. The large-sample or bulk quantized Hall (QH) regime is described by the usual localization picture, whereas the small-sample or edge regime is discussed within the compressible/incompressible strips picture, known as the screening theory of QH edges. Utilizing the unusually sharp edge profiles of the CEO samples, a Hall bar design is proposed to manipulate the edge potential profile from smooth to extremely sharp. By making use of a side-gate perpendicular to the two-dimensional electron system, it is shown that the plateau widths can be changed or even eliminated altogether. Hence, the visibility of IQHE is strongly influenced when adjusting the edge potential profile and/or changing the dc current direction under high currents in the nonlinear transport regime. As a second investigation, we consider two different types of ohmic contacts, namely highly transmitting (ideal) and highly reflecting (non-ideal) contacts. We show that if the injection contacts are non-ideal, but still ohmic, it is possible to measure directly the non-quantized transport taking place at the bulk of the CEO samples. The results of the experiments we propose will clarify the influence of the edge potential profile and the quality of the contacts, under QH conditions. (paper)

  13. SHARP pre-release v1.0 - Current Status and Documentation

    Mahadevan, Vijay S. [Argonne National Lab. (ANL), Argonne, IL (United States); Rahaman, Ronald O. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-09-30

    The NEAMS Reactor Product Line effort aims to develop an integrated multiphysics simulation capability for the design and analysis of future generations of nuclear power plants. The Reactor Product Line code suite’s multi-resolution hierarchy is being designed to ultimately span the full range of length and time scales present in relevant reactor design and safety analyses, as well as scale from desktop to petaflop computing platforms. In this report, building on a several previous report issued in September 2014, we describe our continued efforts to integrate thermal/hydraulics, neutronics, and structural mechanics modeling codes to perform coupled analysis of a representative fast sodium-cooled reactor core in preparation for a unified release of the toolkit. The work reported in the current document covers the software engineering aspects of managing the entire stack of components in the SHARP toolkit and the continuous integration efforts ongoing to prepare a release candidate for interested reactor analysis users. Here we report on the continued integration effort of PROTEUS/Nek5000 and Diablo into the NEAMS framework and the software processes that enable users to utilize the capabilities without losing scientific productivity. Due to the complexity of the individual modules and their necessary/optional dependency library chain, we focus on the configuration and build aspects for the SHARP toolkit, which includes capability to autodownload dependencies and configure/install with optimal flags in an architecture-aware fashion. Such complexity is untenable without strong software engineering processes such as source management, source control, change reviews, unit tests, integration tests and continuous test suites. Details on these processes are provided in the report as a building step for a SHARP user guide that will accompany the first release, expected by Mar 2016.

  14. Comparison of manual vacuum aspiration and sharp curettage in the treatment of first trimester abortions

    Iftikhar, G.; Tanveer, S.; Gilani, T.A.; Gilani, S.T.A.

    2014-01-01

    To compare the safety and efficacy of manual vacuum aspiration and sharp curettage in the treatment of first trimester abortions. Study Design: Randomized controlled trial. Place and Duration of Study: Department of Gynecology, Social Security Hospital Shahdra Lahore in collaboration with Family Health Hospital Johar Town Lahore, from May 2007 to May 2012. Patients and Methods: Six hundred women admitted with the diagnosis of first trimester less than or equal to 12 weeks abortions were randomly assigned, 300 to manual vacuum aspiration (MVA) and 300 to traditional sharp curettage. Diagnosis of abortion was confirmed by last menstrual period, physical examination and ultrasonography. Results: In total of 600 patients, 300 randomly assigned to MVA and another 300 patients assigned to sharp curettage management were having mean age of 31.8 and 33 yrs respectively. Mean parity was in both groups, mean gestational age 8.9 and 8.2 weeks, mean duration of procedure was 6.4 and 5.8 minutes, duration of hospital stay was 4 and 40 hrs, missed abortion in 47% and 43% patients, incomplete abortion in 53% and 57% patients, cervical dilatation was needed in 1% against 53%, 10% against 8 % experienced mild pain in both groups, no patient of incomplete evacuation against 0.6%, uterine perforation in none against 0.3 %, excessive bleeding was experienced by 0.3% against 0.6% patients in both groups, and patient satisfaction rate was 99% against 99.4% in the two groups respectively. Conclusion: In the management of first trimester pregnancy loss, MVA offers a quick solution to the problem with reduced hospital stay and lower rate of complications. (author)

  15. Computational analysis of network activity and spatial reach of sharp wave-ripples.

    Sadullah Canakci

    Full Text Available Network oscillations of different frequencies, durations and amplitudes are hypothesized to coordinate information processing and transfer across brain areas. Among these oscillations, hippocampal sharp wave-ripple complexes (SPW-Rs are one of the most prominent. SPW-Rs occurring in the hippocampus are suggested to play essential roles in memory consolidation as well as information transfer to the neocortex. To-date, most of the knowledge about SPW-Rs comes from experimental studies averaging responses from neuronal populations monitored by conventional microelectrodes. In this work, we investigate spatiotemporal characteristics of SPW-Rs and how microelectrode size and distance influence SPW-R recordings using a biophysical model of hippocampus. We also explore contributions from neuronal spikes and synaptic potentials to SPW-Rs based on two different types of network activity. Our study suggests that neuronal spikes from pyramidal cells contribute significantly to ripples while high amplitude sharp waves mainly arise from synaptic activity. Our simulations on spatial reach of SPW-Rs show that the amplitudes of sharp waves and ripples exhibit a steep decrease with distance from the network and this effect is more prominent for smaller area electrodes. Furthermore, the amplitude of the signal decreases strongly with increasing electrode surface area as a result of averaging. The relative decrease is more pronounced when the recording electrode is closer to the source of the activity. Through simulations of field potentials across a high-density microelectrode array, we demonstrate the importance of finding the ideal spatial resolution for capturing SPW-Rs with great sensitivity. Our work provides insights on contributions from spikes and synaptic potentials to SPW-Rs and describes the effect of measurement configuration on LFPs to guide experimental studies towards improved SPW-R recordings.

  16. Lamina-specific contribution of glutamatergic and GABAergic potentials to hippocampal sharp wave-ripple complexes.

    Schönberger, Jan; Draguhn, Andreas; Both, Martin

    2014-01-01

    The mammalian hippocampus expresses highly organized patterns of neuronal activity which form a neuronal correlate of spatial memories. These memory-encoding neuronal ensembles form on top of different network oscillations which entrain neurons in a state- and experience-dependent manner. The mechanisms underlying activation, timing and selection of participating neurons are incompletely understood. Here we studied the synaptic mechanisms underlying one prominent network pattern called sharp wave-ripple complexes (SPW-R) which are involved in memory consolidation during sleep. We recorded SPW-R with extracellular electrodes along the different layers of area CA1 in mouse hippocampal slices. Contribution of glutamatergic excitation and GABAergic inhibition, respectively, was probed by local application of receptor antagonists into s. radiatum, pyramidale and oriens. Laminar profiles of field potentials show that GABAergic potentials contribute substantially to sharp waves and superimposed ripple oscillations in s. pyramidale. Inhibitory inputs to s. pyramidale and s. oriens are crucial for action potential timing by ripple oscillations, as revealed by multiunit-recordings in the pyramidal cell layer. Glutamatergic afferents, on the other hand, contribute to sharp waves in s. radiatum where they also evoke a fast oscillation at ~200 Hz. Surprisingly, field ripples in s. radiatum are slightly slower than ripples in s. pyramidale, resulting in a systematic shift between dendritic and somatic oscillations. This complex interplay between dendritic excitation and perisomatic inhibition may be responsible for the precise timing of discharge probability during the time course of SPW-R. Together, our data illustrate a complementary role of spatially confined excitatory and inhibitory transmission during highly ordered network patterns in the hippocampus.

  17. Automated quantitative coronary computed tomography correlates of myocardial ischaemia on gated myocardial perfusion SPECT

    Graaf, Michiel A. de; Boogers, Mark J.; Veltman, Caroline E. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); The Interuniversity Cardiology Institute of The Netherlands, Utrecht (Netherlands); El-Naggar, Heba M.; Bax, Jeroen J.; Delgado, Victoria [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); Broersen, Alexander; Kitslaar, Pieter H.; Dijkstra, Jouke [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Kroft, Lucia J. [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Younis, Imad Al [Leiden University Medical Center, Department of Nuclear Medicine, Leiden (Netherlands); Reiber, Johan H. [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Medis medical imaging systems B.V., Leiden (Netherlands); Scholte, Arthur J. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands)

    2013-08-15

    Automated software tools have permitted more comprehensive, robust and reproducible quantification of coronary stenosis, plaque burden and plaque location of coronary computed tomography angiography (CTA) data. The association between these quantitative CTA (QCT) parameters and the presence of myocardial ischaemia has not been explored. The aim of the present investigation was to evaluate the association between QCT parameters of coronary artery lesions and the presence of myocardial ischaemia on gated myocardial perfusion single-photon emission CT (SPECT). Included in the study were 40 patients (mean age 58.2 {+-} 10.9 years, 27 men) with known or suspected coronary artery disease (CAD) who had undergone multidetector row CTA and gated myocardial perfusion SPECT within 6 months. From the CTA datasets, vessel-based and lesion-based visual analyses were performed. Consecutively, lesion-based QCT was performed to assess plaque length, plaque burden, percentage lumen area stenosis and remodelling index. Subsequently, the presence of myocardial ischaemia was assessed using the summed difference score (SDS {>=}2) on gated myocardial perfusion SPECT. Myocardial ischaemia was seen in 25 patients (62.5 %) in 37 vascular territories. Quantitatively assessed significant stenosis and quantitatively assessed lesion length were independently associated with myocardial ischaemia (OR 7.72, 95 % CI 2.41-24.7, p < 0.001, and OR 1.07, 95 % CI 1.00-1.45, p = 0.032, respectively) after correcting for clinical variables and visually assessed significant stenosis. The addition of quantitatively assessed significant stenosis ({chi} {sup 2} = 20.7) and lesion length ({chi} {sup 2} = 26.0) to the clinical variables and the visual assessment ({chi} {sup 2} = 5.9) had incremental value in the association with myocardial ischaemia. Coronary lesion length and quantitatively assessed significant stenosis were independently associated with myocardial ischaemia. Both quantitative parameters have

  18. Membrane metamaterial resonators with a sharp resonance: A comprehensive study towards practical terahertz filters and sensors

    Yongyao Chen

    2012-06-01

    Full Text Available We investigate the resonant properties of high quality-factor membrane-based metamaterial resonators functioning in the terahertz regime. A number of factors, including the resonator geometry, dielectric loss, and most importantly the membrane thickness are found to extensively influence the resonance strength and quality factor of the sharp resonance. Further studies on the membrane thickness-dependent-sensitivity for sensing applications reveal that high quality-factor membrane metamaterials with a moderate thickness ranging from 10 to 50 μm are the most promising option towards developing realistic integrated terahertz filters and sensors.

  19. Sharp wave/ripple network oscillations and learning-associated hippocampal maps.

    Csicsvari, Jozsef; Dupret, David

    2014-02-05

    Sharp wave/ripple (SWR, 150-250 Hz) hippocampal events have long been postulated to be involved in memory consolidation. However, more recent work has investigated SWRs that occur during active waking behaviour: findings that suggest that SWRs may also play a role in cell assembly strengthening or spatial working memory. Do such theories of SWR function apply to animal learning? This review discusses how general theories linking SWRs to memory-related function may explain circuit mechanisms related to rodent spatial learning and to the associated stabilization of new cognitive maps.

  20. Overexpression of TiERF1 enhances resistance to sharp eyespot in transgenic wheat

    Chen, Liang; Zhang, ZengYan; Liang, HongXia; Liu, HongXia; Du, LiPu; Xu, Huijun; Xin, Zhiyong

    2008-01-01

    Wheat sharp eyespot, primarily caused by a soil-borne fungus Rhizoctonia cerealis, has become one of the most serious diseases of wheat in China. In this study, an ethylene response factor (ERF) gene from a wheat relative Thinopyrum intermedium, TiERF1, was characterized further, transgenic wheat lines expressing TiERF1 were developed, and the resistance of the transgenic wheat lines against R. cerealis was investigated. Southern blotting analysis indicated that at least two copies of the TiE...

  1. Critical β of a D-shaped toroidal plasma with sharp boundary

    Kito, M.

    1981-01-01

    Under the cap-cyclide coordinate system, the marginal stability of a sharp boundary toroidal plasma whose cross section is D shaped is examined using the energy principle. The analytical results are valid for arbitrary b, arbitrary aspect ratio, and arbitrary elongation of the plasma. There exists a maximum elongation for a given aspect ratio. The critical beta b/sub c/ is computed for several aspect ratios and elongations. For given aspect ratio, b/sub c/ increases as long as the elongation increases

  2. The Next Generation of Ground Operations Command and Control; Scripting in C Sharp and Visual Basic

    Ritter, George; Pedoto, Ramon

    2010-01-01

    This slide presentation reviews the use of scripting languages in Ground Operations Command and Control. It describes the use of scripting languages in a historical context, the advantages and disadvantages of scripts. It describes the Enhanced and Redesigned Scripting (ERS) language, that was designed to combine the features of a scripting language and the graphical and IDE richness of a programming language with the utility of scripting languages. ERS uses the Microsoft Visual Studio programming environment and offers custom controls that enable an ERS developer to extend the Visual Basic and C sharp language interface with the Payload Operations Integration Center (POIC) telemetry and command system.

  3. Percutaneous sharp recanalization of a membranous IVC occlusion with an occlusion balloon as a needle target

    Michael D. Rivers-Bowerman, MD, MSc, FRCPC

    2017-09-01

    Full Text Available A 50-year-old male with right upper quadrant symptoms and hepatic dysfunction was found to have multiple dilated hepatic veins (HVs with intrahepatic collateralization and membranous occlusion of the intrahepatic inferior vena cava (IVC consistent with primary Budd–Chiari syndrome. Venacavograms depicted drainage of the intrahepatic collaterals through a left-sided HV entering the IVC above the level of the occlusion. Sharp recanalization of the membranous IVC occlusion was performed with an occlusion balloon as a needle target under echocardiographic monitoring followed by balloon angioplasty with restoration of IVC patency. Clinical, laboratory, and venographic procedural success has been demonstrated to 9 months with minimal residual stenosis.

  4. Spontaneous passage of long, sharp gastrointestinal foreign body in a child.

    Karthikeyan, Vilvapathy Senguttuvan; Ansari, Mohammed Gaffoor; Suresh, Ramasamy; Easwaran, Bettaiyagowder

    2015-01-19

    Foreign body (FB) ingestion is a common problem in children. Up to 90% of these FBs pass spontaneously. FBs reaching the stomach usually pass out spontaneously. Exceptions to this spontaneous passage include a long FB that cannot cross the pylorus, duodenum or ileocaecal junction. We present a case of a 9-year boy who accidentally ingested a long paper pin, which spontaneously passed in 26 h. This case is being reported to highlight the successful spontaneous passage of a 4 cm long sharp foreign body in a child. 2015 BMJ Publishing Group Ltd.

  5. Discharge coefficient of a rectangular sharp-edged broad-crested weir

    Zachoval Zbyněk; Knéblová Michaela; Roušar Ladislav; Rumann Ján; Šulc Jan

    2014-01-01

    his paper is concerned with the determination of the relationship for the calculation of the discharge coefficient at free overflow over a rectangular sharp-edged broad-crested weir without lateral contraction. The determination was made on the basis of new measurement in a range of the relative thickness of the weir from 0.12 to 0.30 and newly in a large range of relative height of the weir extremely from 0.24 to 6.8 which greatly expands the application possibilities of low weirs. In additi...

  6. Thermally induced high frequency random amplitude fatigue damage at sharp notches

    Lewis, M.W.J.

    1992-01-01

    Experiments have been performed using the SUPERSOMITE facility to investigate the initiation and growth of fatigue cracks at the tips of sharp surface notches subjected to random thermally-induced stress. The experimental situation is complex involving plasticity, random amplitude loading and heat transfer medium/surface coupling. Crack initiation and growth prediction have been considered using the Creager and Neuber methods to compute the strain ranges in the vicinity of the notch root. Good agreement has been obtained between the experimental results and theoretical predictions. The paper reports the results of the analysis of the notch behavior

  7. Implementing a sharps injury reduction program at a charity hospital in India.

    Gramling, Joshua J; Nachreiner, Nancy

    2013-08-01

    Health care workers in India are at high risk of developing bloodborne infections from needlestick injuries. Indian hospitals often do not have the resources to invest in safety devices and protective equipment to decrease this risk. In collaboration with hospital staff, the primary author implemented a sharps injury prevention and biomedical waste program at an urban 60-bed charity hospital in northern India. The program aligned with hospital organizational objectives and was designed to be low-cost and sustainable. Occupational health nurses working in international settings or with international workers should be aware of employee and employer knowledge and commitment to occupational health and safety. Copyright 2013, SLACK Incorporated.

  8. Three-dimensional vibrations of cylindrical elastic solids with V-notches and sharp radial cracks

    McGee, O. G.; Kim, J. W.

    2010-02-01

    This paper provides free vibration data for cylindrical elastic solids, specifically thick circular plates and cylinders with V-notches and sharp radial cracks, for which no extensive previously published database is known to exist. Bending moment and shear force singularities are known to exist at the sharp reentrant corner of a thick V-notched plate under transverse vibratory motion, and three-dimensional (3-D) normal and transverse shear stresses are known to exist at the sharp reentrant terminus edge of a V-notched cylindrical elastic solid under 3-D free vibration. A theoretical analysis is done in this work utilizing a variational Ritz procedure including these essential singularity effects. The procedure incorporates a complete set of admissible algebraic-trigonometric polynomials in conjunction with an admissible set of " edge functions" that explicitly model the 3-D stress singularities which exist along a reentrant terminus edge (i.e., α>180°) of the V-notch. The first set of polynomials guarantees convergence to exact frequencies, as sufficient terms are retained. The second set of edge functions—in addition to representing the corner stress singularities—substantially accelerates the convergence of frequency solutions. This is demonstrated through extensive convergence studies that have been carried out by the investigators. Numerical analysis has been carried out and the results have been given for cylindrical elastic solids with various V-notch angles and depths. The relative depth of the V-notch is defined as (1- c/ a), and the notch angle is defined as (360°- α). For a very small notch angle (1° or less), the notch may be regarded as a "sharp radial crack." Accurate (four significant figure) frequencies are presented for a wide spectrum of notch angles (360°- α), depths (1- c/ a), and thickness ratios ( a/ h for plates and h/ a for cylinders). An extended database of frequencies for completely free thick sectorial, semi-circular, and

  9. Lacosamide and Levetiracetam Have No Effect on Sharp-Wave Ripple Rate

    Kudláček, Jan; Chvojka, Jan; Pošusta, Antonín; Kováčová, Ľubica; Hong, S.B.; Weiss, S.; Volná, K.; Marusič, P.; Otáhal, Jakub; Jiruška, Přemysl

    2017-01-01

    Roč. 8, Dec 21 (2017), č. článku 687. ISSN 1664-2295 R&D Projects: GA ČR(CZ) GA14-02634S; GA ČR(CZ) GA15-08565S; GA MZd(CZ) NV15-29835A; GA MZd(CZ) NV17-28427A Institutional support: RVO:67985823 Keywords : high-frequency oscillations * sharp-wave ripples * levetiracetam * lacosamide * antiepileptic drugs Subject RIV: FH - Neurology OBOR OECD: Neurosciences (including psychophysiology Impact factor: 3.552, year: 2016

  10. Tracking sharp interface of two fluids by the CIP (cubic-interpolated propagation) scheme

    Yabe, T.; Xiao, F.

    1993-01-01

    A method to treat a sharp discontinuity by the density function is proposed. The surface of the density function is described by one grid throughout the calculation even when the surface is largely distorted. This description is made possible by the CIP method combined with variable transformation. This scheme is applied to the linear wave propagation in one- and two-dimensions. In the nonlinear case, the injection of heavier fluid into lighter fluid his calculated and the winding of mushroom structure is successfully treated by the density function. (author)

  11. Exercise induced ST elevation and residual myocardial ischemia in previous myocardial infarction

    Shimonagata, Tsuyoshi; Nishimura, Tsunehiko; Uehara, Toshiisa; Hayashida, Kohei; Saito, Muneyasu; Sumiyoshi, Tetsuya

    1987-01-01

    The purpose of this study was to evaluate the clinical significance of stress induced ST elevation on infarcted area in 65 patients with previous myocardial infarction (single vessel disease) who had stress thallium scan. Stress induced ST changes on infarcted area were compared with quantitative assessment of myocardial ischemia (thallium ischemic score; TIS) and extent of myocardial infarction (defect score; DS) derived from circumferential profile analysis. In patients with previous myocardial infarction in less than 3 month from the onset (n = 36), left ventricular ejection fraction (LVEF) and extent of abnormal LV wall motion were not significantly different between patients with stress induced ST elevation ( ≥ 2 mm, n = 26) and those with stress induced ST elevation ( < 2 mm, n = 10), while, in patients with previous myocardial infarction in more than 3 month (n = 29), patients with stress induced ST elevation ( ≥ 2 mm, n = 15) showed left ventricular dyskinesis more frequently than those with ST elevation ( < 2 mm, n = 14). In addition, the former showed significantly higher DS and significantly lower TIS than the latter. In patients with previous myocardial infarction in less than 3 month, patients with ST elevation ( ≥ 2 mm, n = 15) with prominent upright T wave (n = 15) had transient thallium defect in infarcted area in 73 % and they had significantly higher LVEF and TIS than those with ST elevation ( < 2 mm, n = 11). These results indicated that ST elevation in infarcted area reflect different significance according to the recovery of injured myocardium and stress induced ST elevation with prominent upright T wave in infarcted area reflect residual myocardial ischemia in less than 3 month from the onset of myocardial infarction. (author)

  12. Usefulness of myocardial parametric imaging to evaluate myocardial viability in experimental and in clinical studies.

    Korosoglou, G; Hansen, A; Bekeredjian, R; Filusch, A; Hardt, S; Wolf, D; Schellberg, D; Katus, H A; Kuecherer, H

    2006-03-01

    To evaluate whether myocardial parametric imaging (MPI) is superior to visual assessment for the evaluation of myocardial viability. Myocardial contrast echocardiography (MCE) was assessed in 11 pigs before, during, and after left anterior descending coronary artery occlusion and in 32 patients with ischaemic heart disease by using intravenous SonoVue administration. In experimental studies perfusion defect area assessment by MPI was compared with visually guided perfusion defect planimetry. Histological assessment of necrotic tissue was the standard reference. In clinical studies viability was assessed on a segmental level by (1) visual analysis of myocardial opacification; (2) quantitative estimation of myocardial blood flow in regions of interest; and (3) MPI. Functional recovery between three and six months after revascularisation was the standard reference. In experimental studies, compared with visually guided perfusion defect planimetry, planimetric assessment of infarct size by MPI correlated more significantly with histology (r2 = 0.92 versus r2 = 0.56) and had a lower intraobserver variability (4% v 15%, p < 0.05). In clinical studies, MPI had higher specificity (66% v 43%, p < 0.05) than visual MCE and good accuracy (81%) for viability detection. It was less time consuming (3.4 (1.6) v 9.2 (2.4) minutes per image, p < 0.05) than quantitative blood flow estimation by regions of interest and increased the agreement between observers interpreting myocardial perfusion (kappa = 0.87 v kappa = 0.75, p < 0.05). MPI is useful for the evaluation of myocardial viability both in animals and in patients. It is less time consuming than quantification analysis by regions of interest and less observer dependent than visual analysis. Thus, strategies incorporating this technique may be valuable for the evaluation of myocardial viability in clinical routine.

  13. TOWARD THE QUESTION OF ISCHEMIC MYOCARDIAL DYSFUNCTION

    V. V. Kalyuzhin

    2014-01-01

    Full Text Available The authors of the review have analyzed papers published on the problem of ischemic myocardial dysfunction. They begin with a definition of the term “ischemia” (derived from two Greek words: ischō, meaning to hold back, and haima, meaning blood - a condition at which the arterial blood flow is insufficient to provide enough oxygen to prevent intracellular respiration from shifting from the aerobic to the anaerobic form. The poor rate of ATP generation from this process causes a decrease in cellular ATP, a concomitant rise in ADP, and ultimately, to depression inotropic (systolic and lusitropic (diastolic function of the affected segments of the myocardium. But with such simplicity of basic concepts, the consequences of ischemia so diverse. Influence of an ischemia on myocardial function so unequally at different patients, which is almost impossible to find two identical cases (as in the case of fingerprints. It depends on the infinite variety of lesions of coronary arteries, reperfusion (time and completeness of restoration of blood flow and reactions of a myocardium which, apparently, has considerable flexibility in its response. Ischemic myocardial dysfunction includes a number of discrete states, such as acute left ventricular failure in angina, acute myocardial infarction, ischemic cardiomyopathy, stunning, hibernation, pre- and postconditioning. There are widely differing underlying pathophysiologic states. The possibility exists that several of these states can coexist.

  14. Novel strategies for enhancing myocardial infarction

    Liu, J.

    2011-01-01

    Ischemic heart disease is a leading cause of morbidity and mortality worldwide. Massive cell loss initiated a series of cascade events upon ischemic injury. Enourmous effort has been put to investigate strategies for enhancing myocardial healing. Cell therapy emerges as a promising strategy for

  15. Adverse events while awaiting myocardial revascularization

    Head, Stuart J.; da Costa, Bruno R.; Beumer, Berend

    2017-01-01

    OBJECTIVES: The aim of the current study was to estimate adverse event rates while awaiting myocardial revascularization and review criteria for prioritizing patients. METHODS: A PubMed search was performed on 19 January 2015, to identify English-language, original, observational studies reportin...

  16. Symptomatic myocardial bridging or cardiac Whipple's Diseas

    Cabral,Virgínia L. Ribeiro; Knecht,Daniella; Pego,Regina Célia; Silva,Nuno C. Figueiredo

    2003-01-01

    This report concerns a patient with articular and cardiac manifestations of Whipple's disease. The disease was diagnosed only when gastrointestinal symptoms had appeared, because all cardiac symptoms were attributed exclusively to myocardial bridging. After 18 months of treatment with trimethoprim-sulfamethoxazole, the patient is fully asymptomatic with a normal echocardiogram.

  17. Rehabilitation of Patients Following Myocardial Infarction.

    Blumenthal, James A.; Emery, Charles F.

    1988-01-01

    Examines three behavioral strategies in cardiac rehabilitation (CR) for formal treatment for physical and psychosocial sequelae of myocardial infarction (MI): exercise therapy, Type A modification, and nonspecific psychological therapies. Concludes CR improves the quality of life among post-MI patients, but does not prolong life or significantly…

  18. The treatment of perioperative myocardial infarctions following ...

    Background: Perioperative myocardial infarction (PMI) is a common complication following noncardiac surgery, with a 30-day mortality of 10-20%. Effective therapeutic interventions are of public health importance. Method: This is a systematic review, aimed to determine the evidence for therapies following PMI. Results: A ...

  19. Statins and perioperative myocardial infarction. | Levin | Southern ...

    The growing prevalence of atherosclerosis means that perioperative myocardial infarction (PMI) is of significant concern to anesthesiologists. Perioperative revascularization (if indicated medically), beta blockade (in high risk patients) and statin therapy are therapeutic modalities that are currently employed to reduce PMI.

  20. Safety and feasibility of local myocardial hypothermia

    Otterspoor, L.C.; van 't Veer, M.; van Nunen, L.X.; Wijnbergen, I.F.; Tonino, W.A.L.; Pijls, N.H.J.

    2016-01-01

    Background In ST-elevation myocardial infarction (STEMI), reduction in time to reperfusion of the occluded coronary artery reduces infarct size. In animal models, an additional reduction of infarct size was observed when hypothermia was induced before reperfusion, despite a longer ischemic time.

  1. Symptomatic myocardial bridging or cardiac Whipple's Diseas

    Cabral Virgínia L. Ribeiro

    2003-01-01

    Full Text Available This report concerns a patient with articular and cardiac manifestations of Whipple's disease. The disease was diagnosed only when gastrointestinal symptoms had appeared, because all cardiac symptoms were attributed exclusively to myocardial bridging. After 18 months of treatment with trimethoprim-sulfamethoxazole, the patient is fully asymptomatic with a normal echocardiogram.

  2. Does heavy physical exertion trigger myocardial infarction?

    Hallqvist, J; Möller, J; Ahlbom, A

    2000-01-01

    To study possible triggering of first events of acute myocardial infarction by heavy physical exertion, the authors conducted a case-crossover analysis (1993-1994) within a population-based case-referent study in Stockholm County, Sweden (the Stockholm Heart Epidemiology Program). Interviews were...

  3. Surgical myocardial revascularization without extracorporeal circulation

    Salomón Soriano Ordinola Rojas

    2003-05-01

    Full Text Available OBJECTIVE: To assess the immediate postoperative period of patients undergoing myocardial revascularization without extracorporeal circulation with different types of grafts. METHODS: One hundred and twelve patients, 89 (79.5% of whom were males, were revascularized without extracorporeal circulation. Their ages ranged from 39 to 85 years. The criteria for indicating myocardial revascularization without extracorporeal circulation were as follows: revascularized coronary artery caliber > 1.5 mm, lack of intramyocardial trajectory on coronary angiography, noncalcified coronary arteries, and tolerance of the heart to the different rotation maneuvers. RESULTS: Myocardial revascularization without extracorporeal circulation was performed in 112 patients. Three were converted to extracorporeal circulation, which required a longer hospital stay but did not impact mortality. During the procedure, the following events were observed: atrial fibrillation in 10 patients, ventricular fibrillation in 4, total transient atrioventricular block in 2, ventricular extrasystoles in 58, use of a device to retrieve red blood cells in 53, blood transfusion in 8, and arterial hypotension in 89 patients. Coronary angiography was performed in 20 patients on the seventh postoperative day when the grafts were patent. CONCLUSION: Myocardial revascularization without extracorporeal circulation is a reproducible technique that is an alternative for treating ischemic heart disease.

  4. Management of myocardial damage in muscular dystrophy

    Tamura, Takuhisa

    2011-01-01

    Heart failure (HF) is a fatal complication in many muscular dystrophy cases and has become the most common cause of death in Duchenne muscular dystrophy (DMD) since 2001. HF deaths in DMD occur in young patients and increase, along with respiratory failure, in older patients. Managing HF, therefore, is the most important component of DMD treatment. Management of HF is necessary in DMD patients of all ages because myocardial damage progresses regardless of age and disability. Electrocardiography, echocardiography, myocardial single-photon emission computed tomography (SPECT), and natriuretic peptides are used for the diagnosis of myocardial damage and chronic HF. Tissue Doppler echocardiography is in particularly useful for early detection of minute myocardial damage and dysfunction in DMD. The first-line drugs for chronic HF are angiotensin-converting enzyme inhibitors, and the prognosis of DMD patients has been improved using these drugs and beta-blockers. Diuretics are added in the presence of pulmonary congestion. Digoxin is most effective at a blood level of 0.5-0.8 ng/mL because of its pharmacokinetics in DMD. Surgical treatment may be necessary in cases of intractable HF. Cardiac resynchronization therapy (biventricular pacing), a treatment with an artificial pacemaker, is indicated for cases that meet specific criteria, including HF with ventricular dyssynchrony. Applications of partial left ventriculectomy (Batista procedure) and left ventricular assist devices in muscular dystrophy are likely in the near future. (author)

  5. Mesenchymal Stem Cells : Promising for Myocardial Regeneration?

    Przybyt, Ewa; Harmsen, Martin C.

    The pandemic of cardiovascular disease is continuously expanding as the result of changing life styles and diets throughout the Old and New World. Immediate intervention therapy saves the lives of many patients after acute myocardial infarction (MI). However, for many this comes at the price of

  6. Quantitative assessment of 201TlCl myocardial SPECT

    Uehara, Toshiisa

    1987-01-01

    Clinical evaluation of the quantitative analysis of Tl-201 myocardial tomography by SPECT (Single Photon Emission Computed Tomography) was performed in comparison with visual evaluation. The method of quantitative analysis has been already reported in our previous paper. In this study, the program of re-standardization in the case of lateral myocardial infarction was added. This program was useful mainly for the evaluation of lesions in the left circumflex coronary artery. Regarding the degree of diagnostic accuracy of myocardial infarction in general, quantitative evaluation of myocardial SPECT images was highest followed by visual evaluation of myocardial SPECT images, and visual evaluation of myocardial planar images. However, in the case of anterior myocardial infarction, visual evaluation of myocardial SPECT images has almost the same detectability as quantitative evaluation of myocardial SPECT images. In the case of infero-posterior myocardial infarction, quantitative evaluation was superior to visual evaluation. As for specificity, quantitative evaluation of SPECT images was slightly inferior to visual evaluation of SPECT images. An infarction map was made by quantitative analysis and this enabled us to determine the infarction site, extent and degree according to easily recognizable patterns. As a result, the responsible coronary artery lesion could be inferred correctly and the calculated infarction score could be correlated with the residual left ventricular function after myocardial infarction. (author)

  7. delta-Opioid-induced pharmacologic myocardial hibernation during cardiopulmonary resuscitation.

    Fang, Xiangshao; Tang, Wanchun; Sun, Shijie; Weil, Max Harry

    2006-12-01

    Cardiac arrest and cardiopulmonary resuscitation is an event of global myocardial ischemia and reperfusion, which is associated with severe postresuscitation myocardial dysfunction and fatal outcome. Evidence has demonstrated that mammalian hibernation is triggered by cyclic variation of a delta-opiate-like compound in endogenous serum, during which the myocardial metabolism is dramatically reduced and the myocardium tolerates the stress of ischemia and reperfusion without overt ischemic and reperfusion injury. Previous investigations also proved that the delta-opioid agonist elicited the cardioprotection in a model of regional ischemic intact heart or myocyte. Accordingly, we were prompted to search for an alternative intervention of pharmacologically induced myocardial hibernation that would result in rapid reductions of myocardial metabolism and therefore minimize the myocardial ischemic and reperfusion injury during cardiac arrest and cardiopulmonary resuscitation. Prospective, controlled laboratory study. University-affiliated research laboratory. In the series of studies performed in the established rat and pig model of cardiac arrest and cardiopulmonary resuscitation, the delta-opioid receptor agonist, pentazocine, was administered during ventricular fibrillation. : The myocardial metabolism reflected by the concentration of lactate, or myocardial tissue PCO2 and PO2, is dramatically reduced during cardiac arrest and cardiopulmonary resuscitation. These are associated with less severe postresuscitation myocardial dysfunction and longer duration of postresuscitation survival. delta-Opioid-induced pharmacologic myocardial hibernation is an option to minimize the myocardial ischemia and reperfusion injury during cardiac arrest and cardiopulmonary resuscitation.

  8. THE DETERMINATION OF THE SHARPNESS DEPTH BORDERS AND CORRESPONDING PHOTOGRAPHY AND VIDEO RECORDING PARAMETERS FOR CONTEMPORARY VIDEO TECHNOLOGY

    E. G. Zaytseva

    2011-01-01

    Full Text Available The method of determination of the sharpness depth borders was improved for contemporary video technology. The computer programme for determination of corresponding video recording parameters was created.

  9. Myocardial perfusion imaging in hyperthrophic cardiomyopathy

    Moorin, B.

    1998-01-01

    Full text: Patients with Hyperthrophic Cardiomyopathy (HCM) frequently suffer from syncope and cardiac arrest which may lead to sudden death. This is most often caused by ventricular arrhythmia's in adults, however in young patients the mechanisms are thought to be different. Ischaemia may play a significant role even in young asymptomatic HCM patients. The mechanisms of ischaemic development in HCM differ from those in the 'normal' myocardium (Due to intramural small vessel abnormalities and abnormal myocellular architecture). In HCM the coronary microcirculation is most often affected and massive hypertrophy means more energy is required to promote contraction thus increasing oxygen demand and compounding the effects of any ischaemic changes. A case of a 12 year old HCM patient is presented who has symptoms of syncope associated with exercise whose mother died suddenly of cardiac arrest developed from HCM. A myocardial perfusion rest/stress study was undertaken to detect any underlying myocardial ischaemia. Myocardial perfusion scintigraphy demonstrates any reduction in the microcirculation in addition to that present in the macrocirculation, unlike angiography which will only detect the latter. In this case the scan clearly showed evidence of ischaemia in the lateral wall and this may be an explanation for her episodes of syncope. We suggest an algorithm or the routine work-up of young patients with HCM which makes aggressive use of myocardial perfusion imaging to detect ischaemic changes. This may identify patients who are at higher risk and will assist with treatment decisions. We feel myocardial perfusion scintigraphy is a sensitive non-invasive accurate method of detecting microcirculatory ischaemia and is thus invaluable in HCM patients

  10. Clinical use of 201Tl myocardial scintigraphy

    Senda, Kohei; Imaeda, Takeyoshi; Kato, Toshimitsu; Asada, Shuichi; Doi, Hidetaka

    1977-01-01

    Myocardial imaging with 201 Tl and scinticamera was studied experimentally using specially designed phantoms and clinically in 23 patients with myocardial infarction or other heart disease. In the phantom experiment, quality of image, accumulative count rate, and detectability of the defect were compared to obtain the best technique for their detection, using four different collimators, i.e., converging, pin-hole, 4000-hole, and 140 keV high-resolution, at two photopeak levels of 201 Tl of 75 and 167 keV, and combining a radiation absorber. In patient examination, myocardial images taken at different periods after injection, different detecting conditions of the scinticamera, and various detecting projections were compared. Images of the converging collimator at the 75 keV photopeak revealed considerably higher accumulative counts and relatively higher quality than those of other detecting conditions. It was necessary to take as many images as possible in various projections, in order to detect the location and size of the myocardial ischemic lesion because the lesion was demonstrated as a clear defect only in profile. It became evident that images taken between about 25 and 90 min delineated the myocardium more clearly than those taken in other periods. Normal images taken in 8 patients without ischemic heart disease appeared in the shape of a doughnut of horseshoe, demonstrating mainly the left venticular myocardium. The image was faint in the region of the aortic or mitral valve and thin in the region of the apical wall. A faint image of the right ventricular myocardium was sometimes seen. In 3 patients with valvular heart disease, findings suggested changes in the thickness of myocardium and the distribution of coronary blood flow. In 11 of 12 patients with old myocardial infarction, the location and size of the lesion was detected. (Evans, J.)

  11. Eigenstate Phase Transitions

    Zhao, Bo

    Phase transitions are one of the most exciting physical phenomena ever discovered. The understanding of phase transitions has long been of interest. Recently eigenstate phase transitions have been discovered and studied; they are drastically different from traditional thermal phase transitions. In eigenstate phase transitions, a sharp change is exhibited in properties of the many-body eigenstates of the Hamiltonian of a quantum system, but not the thermal equilibrium properties of the same system. In this thesis, we study two different types of eigenstate phase transitions. The first is the eigenstate phase transition within the ferromagnetic phase of an infinite-range spin model. By studying the interplay of the eigenstate thermalization hypothesis and Ising symmetry breaking, we find two eigenstate phase transitions within the ferromagnetic phase: In the lowest-temperature phase the magnetization can macroscopically oscillate by quantum tunneling between up and down. The relaxation of the magnetization is always overdamped in the remainder of the ferromagnetic phase, which is further divided into phases where the system thermally activates itself over the barrier between the up and down states, and where it quantum tunnels. The second is the many-body localization phase transition. The eigenstates on one side of the transition obey the eigenstate thermalization hypothesis; the eigenstates on the other side are many-body localized, and thus thermal equilibrium need not be achieved for an initial state even after evolving for an arbitrary long time. We study this many-body localization phase transition in the strong disorder renormalization group framework. After setting up a set of coarse-graining rules for a general one dimensional chain, we get a simple "toy model'' and obtain an almost purely analytical solution to the infinite-randomness critical fixed point renormalization group equation. We also get an estimate of the correlation length critical exponent nu

  12. Design and experimentation of an empirical multistructure framework for accurate, sharp and reliable hydrological ensembles

    Seiller, G.; Anctil, F.; Roy, R.

    2017-09-01

    This paper outlines the design and experimentation of an Empirical Multistructure Framework (EMF) for lumped conceptual hydrological modeling. This concept is inspired from modular frameworks, empirical model development, and multimodel applications, and encompasses the overproduce and select paradigm. The EMF concept aims to reduce subjectivity in conceptual hydrological modeling practice and includes model selection in the optimisation steps, reducing initial assumptions on the prior perception of the dominant rainfall-runoff transformation processes. EMF generates thousands of new modeling options from, for now, twelve parent models that share their functional components and parameters. Optimisation resorts to ensemble calibration, ranking and selection of individual child time series based on optimal bias and reliability trade-offs, as well as accuracy and sharpness improvement of the ensemble. Results on 37 snow-dominated Canadian catchments and 20 climatically-diversified American catchments reveal the excellent potential of the EMF in generating new individual model alternatives, with high respective performance values, that may be pooled efficiently into ensembles of seven to sixty constitutive members, with low bias and high accuracy, sharpness, and reliability. A group of 1446 new models is highlighted to offer good potential on other catchments or applications, based on their individual and collective interests. An analysis of the preferred functional components reveals the importance of the production and total flow elements. Overall, results from this research confirm the added value of ensemble and flexible approaches for hydrological applications, especially in uncertain contexts, and open up new modeling possibilities.

  13. Core Promoter Plasticity Between Maize Tissues and Genotypes Contrasts with Predominance of Sharp Transcription Initiation Sites.

    Mejía-Guerra, María Katherine; Li, Wei; Galeano, Narmer F; Vidal, Mabel; Gray, John; Doseff, Andrea I; Grotewold, Erich

    2015-12-01

    Core promoters are crucial for gene regulation, providing blueprints for the assembly of transcriptional machinery at transcription start sites (TSSs). Empirically, TSSs define the coordinates of core promoters and other regulatory sequences. Thus, experimental TSS identification provides an essential step in the characterization of promoters and their features. Here, we describe the application of CAGE (cap analysis of gene expression) to identify genome-wide TSSs used in root and shoot tissues of two maize (Zea mays) inbred lines (B73 and Mo17). Our studies indicate that most TSS clusters are sharp in maize, similar to mice, but distinct from Arabidopsis thaliana, Drosophila melanogaster, or zebra fish, in which a majority of genes have broad-shaped TSS clusters. We established that ∼38% of maize promoters are characterized by a broader TATA-motif consensus, and this motif is significantly enriched in genes with sharp TSSs. A noteworthy plasticity in TSS usage between tissues and inbreds was uncovered, with ∼1500 genes showing significantly different dominant TSSs, sometimes affecting protein sequence by providing alternate translation initiation codons. We experimentally characterized instances in which this differential TSS utilization results in protein isoforms with additional domains or targeted to distinct subcellular compartments. These results provide important insights into TSS selection and gene expression in an agronomically important crop. © 2015 American Society of Plant Biologists. All rights reserved.

  14. Account for the surface tension in hydraulic modeling of the weir with a sharp threshold

    Medzveliya Manana Levanovna

    Full Text Available In the process of calculating and simulating water discharge in free channels it is necessary to know the flow features in case of small values of Reynolds and Weber numbers. The article considers the influence of viscosity and surface tension on the coefficient of a weir flow with sharp threshold. In the article the technique of carrying out experiments is stated, the equation is presented, which considers the influence of all factors: pressure over a spillway threshold, threshold height over a course bottom, speed of liquid, liquid density, dynamic viscosity, superficial tension, gravity acceleration, unit discharge, the width of the course. The surface tension and liquid density for the applied liquids changed a little. In the rectangular tray (6000x100x200 spillway with a sharp threshold was established. It is shown that weir flow coefficient depends on Reynolds number (in case Re < ~ 2000 and Webers number. A generalized expression for determining weir flow coefficient considering the influence of the forces of viscosity and surface tension is received.

  15. Critical applied stresses for a crack initiation from a sharp V-notch

    L. Náhlík

    2014-10-01

    Full Text Available The aim of the paper is to estimate a value of the critical applied stress for a crack initiation from a sharp V-notch tip. The classical approach of the linear elastic fracture mechanics (LELM was generalized, because the stress singularity exponent differs from 0.5 in the studied case. The value of the stress singularity exponent depends on the V-notch opening angle. The finite element method was used for a determination of stress distribution in the vicinity of the sharp V-notch tip and for the estimation of the generalized stress intensity factor depending on the V-notch opening angle. Critical value of the generalized stress intensity factor was obtained using stability criteria based on the opening stress component averaged over a critical distance d from the V-notch tip and generalized strain energy density factor. Calculated values of the critical applied stresses were compared with experimental data from the literature and applicability of the LEFM concept is discussed.

  16. Crustal thickness and Moho sharpness beneath the Midcontinent rift from receiver functions

    Moikwathai Moidaki

    2013-02-01

    Full Text Available The Mesoproterozoic Midcontinent rift (MCR in the central US is an approximately 2000 km long, 100 km wide structure from Kansas to Michigan. During the 20-40 million years of rifting, a thick (up to 20 km layer of basaltic lava was deposited in the rift valleys. Quantifying the effects of the rifting and associated volcanic eruptions on the structure and composition of the crust and mantle beneath the MCR is important for the understanding of the evolution of continental lithosphere. In this study we measure the crustal thickness (H, and the sharpness of the Moho (R at about 24 portable and permanent stations in Iowa, Kansas, and South Dakota by stacking Pto- S converted waves (PmS and their multiples (PPmS and PSmS. Under the assumption that the crustal mean velocity in the study area is the same as the IASP91 earth model, we find a significantly thickened crust beneath the MCR of about 53 km. The crustal Vp/Vs ratios increases from about 1.80 off rift to as large as 1.95 within the rift, which corresponds to an increase of Poisson’s ratio from 0.28 to 0.32, suggesting a more mafic crust beneath the MCR. The R measurements are spatially variable and are relatively small in the vicinity of the MCR, indicating the disturbance of the original sharp Moho by the rifting and magmatic intrusion and volcanic eruption.

  17. Sharp Trapping Boundaries in the Random Walk of Interplanetary Magnetic Field Lines

    Ruffolo, D.; Chuychai, P.; Meechai, J.; Pongkitiwanichkul, P.; Kimpraphan, N.; Matthaeus, W. H.; Rowlands, G.

    2004-05-01

    Although magnetic field lines in space are believed to undergo a diffusive random walk in the long-distance limit, observed dropouts of solar energetic particles, as well as computer simulations, indicate sharply defined filaments in which interplanetary magnetic field lines have been temporarily trapped. We identify mechanisms that can explain such sharp boundaries in the framework of 2D+slab turbulence, a model that provides a good explanation of solar wind turbulence spectra and the parallel transport of solar energetic particles. Local trapping boundaries (LTBs) are empirically defined as trajectories of 2D turbulence where the mean 2D field is a local maximum. In computer simulations, the filaments (or ``islands'' in the two dimensions perpendicular to the mean field) that are most resistant to slab diffusion correspond closely to the mathematically defined LTBs, that is, there is a mathematical prescription for defining the trapping regions. Furthermore, we provide computational evidence and a theoretical explanation that strong 2D turbulence can inhibit diffusion due to the slab component. Therefore, while these filaments are basically defined by the small-scale topology of 2D turbulence, there can be sharp trapping boundaries where the 2D field is strongest. This work was supported by the Thailand Research Fund, the Rachadapisek Sompoj Fund of Chulalongkorn University, and NASA Grant NAG5-11603. G.R. thanks Mahidol University for its hospitality and the Thailand Commission for Higher Education for travel support.

  18. Disrupting neural activity related to awake-state sharp wave-ripple complexes prevents hippocampal learning.

    Nokia, Miriam S; Mikkonen, Jarno E; Penttonen, Markku; Wikgren, Jan

    2012-01-01

    Oscillations in hippocampal local-field potentials (LFPs) reflect the crucial involvement of the hippocampus in memory trace formation: theta (4-8 Hz) oscillations and ripples (~200 Hz) occurring during sharp waves are thought to mediate encoding and consolidation, respectively. During sharp wave-ripple complexes (SPW-Rs), hippocampal cell firing closely follows the pattern that took place during the initial experience, most likely reflecting replay of that event. Disrupting hippocampal ripples using electrical stimulation either during training in awake animals or during sleep after training retards spatial learning. Here, adult rabbits were trained in trace eyeblink conditioning, a hippocampus-dependent associative learning task. A bright light was presented to the animals during the inter-trial interval (ITI), when awake, either during SPW-Rs or irrespective of their neural state. Learning was particularly poor when the light was presented following SPW-Rs. While the light did not disrupt the ripple itself, it elicited a theta-band oscillation, a state that does not usually coincide with SPW-Rs. Thus, it seems that consolidation depends on neuronal activity within and beyond the hippocampus taking place immediately after, but by no means limited to, hippocampal SPW-Rs.

  19. Background and design of the ACCA-EAPCI registry on ST-segment elevation myocardial infarction of the European Society of Cardiology.

    Zeymer, Uwe; Ludman, Peter; Danchin, Nicolas; Kala, Petr; Maggioni, Aldo P; Weidinger, Franz

    2018-02-01

    Treatment of patients with acute ST-segment elevation myocardial infarction has improved over past decades, with reperfusion therapy being the cornerstone in the acute phase. Based on the results of large randomised trials the current ST-segment elevation myocardial infarction guidelines of the European Society of Cardiology (ESC) recommend acute treatments and secondary prevention therapies. However, there are large variations between ESC countries in the treatment of patients presenting with ST-segment elevation myocardial infarction. Therefore the ESC has initiated a prospective registry to evaluate the current treatments and outcomes of these patients with a special focus on adherence to the ESC guidelines and on differences between countries and regions. This paper describes the methodology and design of the ST-segment elevation myocardial infarction registry conducted in collaboration of the Acute Cardiac Care Association and the European Association of Percutaneous Coronary Intervention.

  20. The influence of surface stress on dislocation emission from sharp and blunt cracks in f.c.c. metals

    Schiøtz, Jakob

    2000-01-01

    We use computer simulations to study the behaviour of atomically sharp and blunted cracks in various fee metals. The simulations use effective medium potentials which contain many-body interactions. We find that when using potentials representing platinum and gold a sharp crack is stable with res......We use computer simulations to study the behaviour of atomically sharp and blunted cracks in various fee metals. The simulations use effective medium potentials which contain many-body interactions. We find that when using potentials representing platinum and gold a sharp crack is stable...... with respect to the emission of a dislocation from the crack tip, whereas for all other metals studied the sharp crack is unstable. This result cannot be explained by existing criteria for the intrinsic ductile/brittle behaviour of crack tips, but is probably caused by surface stresses. When the crack...... is no longer atomically sharp dislocation emission becomes easier in all the studied metals. The effect is relatively strong; the critical stress intensity factor for emission to occur is reduced by up to 20%. This behaviour appears to be caused by the surface stress near the crack tip. The surface stress...