48 results on '"Mátyás, L"'
Search Results
2. Analytic solutions for irregular diffusion equations with concentration dependent diffusion coefficients
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Barna, I. F. and Matyas, L.
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Condensed Matter - Statistical Mechanics ,Mathematical Physics ,Nonlinear Sciences - Exactly Solvable and Integrable Systems - Abstract
We investigate diffusion equations which have concentration dependent diffusion coefficients with physically two relevant Ans\"atze, the self-similar and the traveling wave Ansatz. We found that for power-law concentration dependence some of the results can be expressed with a general analytic implicit formulas for both trial functions. For the self-similar case some of the solutions can be given with a formula containing the hypergeometric function. For the traveling wave case different analytic formulas are given for different exponents. For some physically reasonable parameter sets the direct solutions are given and analyzed in details., Comment: 13 pages 3 figures
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- 2023
3. Even and odd self-similar solutions of the diffusion equation for infinite horizon
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Mátyás, L. and Barna, I. F.
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Physics - Classical Physics ,Mathematics - Analysis of PDEs - Abstract
In the description of transport phenomena an important aspect represents the diffusion. In certain cases the diffusion may appear together with convection. In this paper we study the diffusion equation with the self similar Ansatz. With an appropriate change of variables we found original solutions of diffusion equation for infinite horizon. Here we present the even solutions of diffusion equation for the boundary conditions presented. For completeness the odd solutions are also mentioned as well, as part of the previous works. Finally, the diffusion equation with constant source term is discussed, which also has even and odd solutions, too, Comment: 17 pages, 9 figures
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- 2023
4. Time-dependent analytic solutions for water waves above sea of varying depths
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Barna, I. F., Pocsai, M. A., and Mátyás, L.
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Nonlinear Sciences - Exactly Solvable and Integrable Systems ,Physics - Atmospheric and Oceanic Physics - Abstract
We investigate a hydrodynamic equation system which - with some approximation - is capable to describe the tsunami propagation in the open ocean with the time-dependent self-similar Ansatz. We found analytic solutions how the wave height and velocity behave in time and space for constant and linear seabed functions. First we study waves on open water, where the seabed can be considered relatively constant, sufficiently far from the shore. In the second part of the study we also consider a seabed which is oblique. Finally, we apply the most common traveling wave Ansatz and present almost trivial solutions as well., Comment: 23 pages, 8 figures
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- 2022
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5. Analytical and numerical study of diffusion propelled surface growth phenomena
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Kovács, E., Barna, I.F., Bognár, G., Mátyás, L., and Hriczó, K.
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- 2024
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6. General self-similar solutions of diffusion equation and related constructions
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Barna, Imre F. and Mátyás, L.
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Physics - Classical Physics ,Mathematics - Analysis of PDEs - Abstract
Transport phenomena plays an important role in science and technology. In the wide variety of applications both advection and diffusion may appear. Regarding diffusion, for long times, different type of decay rates are possible for different non-equilibrium systems. After summarizing the existing solutions of the regular diffusion equation, we present not so well known solution derived from three different trial functions, as a key point we present a family of solutions for the case of infinite horizon. By this we tried to make a step toward understanding the different long time decays for different diffusive systems., Comment: 19 pages, 5 figures
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- 2021
7. Self-similar analysis of the time-dependent compressible and incompressible boundary layers including heat conduction
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Barna, Imre F., Hriczó, K., Bognár, G., and Mátyás, L.
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Physics - Fluid Dynamics ,Mathematical Physics - Abstract
We investigate the incompressible and compressible heat conducting boundary layer with applying the two-dimensional self-similar Ansatz. Analytic solutions can be found for the incompressible case which can be expressed with special functions. The parameter dependencies are studied and discussed in details. In the last part of our study we present the ordinary differential equation (ODE) system which is obtained for compressible boundary layers., Comment: 15 pages, 4 figures
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- 2021
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8. Lissajous curves with a finite sum of prime number frequencies
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Barna, Imre F. and Mátyás, L.
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Mathematics - General Mathematics - Abstract
The Ulam spiral inspired us to calculate and present Lissajous curves where the orthogonally added functions are a finite sum of sinus and cosines functions with consecutive prime number frequencies., Comment: 5 pages and 4 figures
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- 2020
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9. Self-similarity analysis of the non-linear Schr\'odinger equation in the Madelung form
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Barna, Imre F., Pocsai, Mihály A., and Mátyás, L.
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Quantum Physics - Abstract
In the present study a particular case of Gross-Pitaevskii or non-linear Schr\"odinger equation is rewritten to a form similar to a hydrodynamic Euler equation using the Madelung transformation. The obtained system of differential equations is highly nonlinear. Regarding solutions, a larger coefficient of the nonlinear term yields stronger deviation of the solution from the linear case., Comment: 11 pages, 2 figures, Accepted in Advances in Mathematical Physics
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- 2018
10. Analytic self-similar solutions of the Oberbeck-Boussinesq equations
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Barna, I. F. and Matyas, L.
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Physics - Fluid Dynamics - Abstract
In this article we will present pure two-dimensional analytic solutions for the coupled non-compressible Newtoniain Navier-Stokes --- with Boussinesq approximation --- and the heat conduction equation. The system was investigated from E.N. Lorenz half a century ago with Fourier series and pioneered the way to the paradigm of chaos. We present a novel analysis of the same system where the key idea is the two-dimensional generalization of the well-known self-similar Ansatz of Barenblatt which will be interpreted in a geometrical way. The results, the pressure, temperature and velocity fields are all analytic and can be expressed with the help of the error functions. The temperature field has a strongly damped oscillating behavior which is an interesting feature., Comment: 13 pages, 4 figures
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- 2015
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11. Analytic Traveling-Wave Solutions of the Kardar-Parisi-Zhang Interface Growing Equation with Different Kind of Noise Terms
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Barna, I. F., Bognár, G., Mátyás, L., Guedda, M., Hriczó, K., Pinelas, Sandra, editor, Graef, John R., editor, Hilger, Stefan, editor, Kloeden, Peter, editor, and Schinas, Christos, editor
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- 2020
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12. Geometrical origin of chaoticity in the bouncing ball billiard
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Mátyás, L. and Barna, I. F.
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Nonlinear Sciences - Chaotic Dynamics - Abstract
We present a study of the chaotic behavior of the bouncing ball billiard. The work is realised on the purpose of finding at least certain causes of separation of the neighbouring trajectories. Having in view the geometrical construction of the system, we report a clear origin of chaoticity of the bouncing ball billiard. By this we claim that in case when the floor is made of arc of circles - in a certain interval of frequencies - a lower bound for the maximal Ljapunov can be evaluated by sem-ianalitical techniques., Comment: We plan to publish this manuscript in a regular journal soon.
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- 2010
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13. Spiral modes in the diffusion of a granular particle on a vibrating surface
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Klages, R., Barna, I. F., and Matyas, L.
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Nonlinear Sciences - Chaotic Dynamics ,Condensed Matter - Statistical Mechanics - Abstract
We consider a particle that is subject to a constant force and scatters inelastically on a vibrating periodically corrugated floor. At small friction and small radius of the circular scatterers the dynamics is dominated by resonances forming spiral structures in phase space. These spiral modes lead to pronounced maxima and minima in the diffusion coefficient as a function of the vibration frequency, as is shown in computer simulations. Our theoretical predictions may be verified experimentally by studying transport of granular matter on vibratory conveyors., Comment: 10 pages, 3 eps-figures
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- 2004
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14. Irregular diffusion in the bouncing ball billiard
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Matyas, L. and Klages, R.
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Nonlinear Sciences - Chaotic Dynamics ,Condensed Matter - Statistical Mechanics - Abstract
We call a system bouncing ball billiard if it consists of a particle that is subjected to a constant vertical force and bounces inelastically on a one-dimendional vibrating periodically corrugated floor. Here we choose circular scatterers that are very shallow, hence this billiard is a deterministic diffusive version of the well-known bouncing ball problem on a flat vibrating plate. Computer simulations show that the diffusion coefficient of this system is a highly irregular function of the vibration frequency exhibiting pronounced maxima whenever there are resonances between the vibration frequency and the average time of flight of a particle. In addition there exist irregularities on finer scales that are due to higher-order dynamical correlations pointing towards a fractal structure of this curve. We analyze the diffusive dynamics by classifying the attracting sets and by working out a simple random walk approximation for diffusion, which is systematically refined by using a Green-Kubo formula., Comment: 26 pages in Latex, Elsevier style; 11 figures
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- 2002
15. Rayleigh–Bènard convection in the generalized Oberbeck–Boussinesq system
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Barna, I.F., Pocsai, M.A., Lökös, S., and Mátyás, L.
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- 2017
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16. Geometrical origin of chaoticity in the bouncing ball billiard
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Mátyás, L. and Barna, I.F.
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- 2011
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17. Knudsen effusion mass spectrometric determination of mixing thermodynamic data of liquid Al–Cu–Sn alloy
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Bencze, L., Milačič, R., Jaćimović, R., Žigon, D., Mátyás, L., and Popovič, A.
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- 2010
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18. The Safety and Efficacy of a Paclitaxel-eluting Wrap for Preventing Peripheral Bypass Graft Stenosis: A 2-Year Controlled Randomized Prospective Clinical Study
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Mátyás, L., Berry, M., Menyhei, G., Tamás, L., Acsády, G., Cuypers, P., Halmos, F., de Vries, A.C., Forgacs, V., Ingenito, G., and Avelar, R.
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- 2008
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19. Analytic Solutions of the Rotating and Stratified Hydrodynamical Equations
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Barna, Imre F., primary and Mátyás, L., primary
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- 2021
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20. Self-similar analysis of a viscous heated Oberbeck–Boussinesq flow system
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Barna, I F, primary, Mátyás, L, additional, and Pocsai, M A, additional
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- 2020
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21. Irregular diffusion in the bouncing ball billiard
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Mátyás, L and Klages, R
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- 2004
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22. Corrigendum: Analytic solutions for the three-dimensional compressible Navier-Stokes equation 2014 Fluid Dyn. Res. 46 055508
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Barna, F, primary and Mátyás, L, additional
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- 2019
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23. Self-Similarity Analysis of the Nonlinear Schrödinger Equation in the Madelung Form
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Barna, Imre F., primary, Pocsai, Mihály A., additional, and Mátyás, L., additional
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- 2018
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24. 10-year stroke prevention after successful carotid endarterectomy for asymptomatic stenosis (ACST-1): a multicentre randomised trial
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Halliday, A, Harrison, M, Hayter, E, Kong, X, Mansfield, A, Marro, J, Pan, H, Peto, R, Potter, J, Rahimi, K, Rau, A, Robertson, S, Streifler, J, Thomas, D, Fraedrich G, Asymptomatic Carotid Surgery Trial Collaborative G. r. o. u. p., Schmidauer, C, Hölzenbein, Th, Huk, I, Haumer, M, Kretschmer, G, Metz, V, Polterauer, P, Teufelsbauer, H, Cras, P, Hendriks, J, Lauwers, P, Van Schil, P, de Souza EB, Dourado, Me, Gurgel, G, Rocha, Gm, Petrov, V, Slabakov, G, Cooper, Me, Gubitz, G, Holness, R, Howes, W, Langille, R, Legg, K, Nearing, S, Mackean, G, Mackay, M, Phillips, Sj, Sullivan, J, Wood, J, Erdelez, L, Sosa, T, Angelides, Ns, Christopoulos, G, Malikidou, A, Pesta, A, Ambler, Z, Mracek, J, Polivka, J, Rohan, V, Sevcik, P, Simaná, J, Benes, V, Kramár, F, Kaste, M, Lepäntalo, M, Soinne, L, Cardon, Jm, Legalou, A, Gengenbach, B, Pfadenhauer, K, Wölfl, Kd, Flessenkämper, I, Klumpp, Bf, Marsch, J, Kolvenbach, R, Pfeiff, T, Sandmann, W, Beyersdorf, F, Hetzel, A, Sarai, K, Schöllhorn, J, Spillner, G, Lutz, Hj, Böckler, D, Maeder, N, Busse, O, Grönniger, J, Haukamp, F, Balzer, K, Knoob, Hg, Roedig, G, Virreira, L, Franke, S, Moll, R, Schneider, J, Dayantas, J, Sechas, Mn, Tsiaza, S, Kiskinis, D, Apor, A, Dzinich, C, Entz, L, Hüttl, K, Jàrànyi, Z, Mogan, I, Nagy, Z, Szabo, A, Varga, D, Juhász, G, Mátyás, L, Hutchinson, M, Mehigan, D, Aladjem, Z, Harah, E, Elmakias, S, Gurvich, D, Yoffe, B, Ben Meir, H, Dagan, L, Karmeli, R, Keren, G, Shimony, A, Weller, B, Avrahami, R, Koren, R, Streifler, Jy, Tabachnik, S, Zelikovski, A, Angiletta, D, Federico, F, Impedovo, G, Marotta, V, Pascazio, L, Regina, G, Andreoli, A, Pozzati, E, Bonardelli, S, Giulini, Sm, Guarneri, B, Caiazzo, P, Mascoli, F, Becchi, G, Masini, R, Santoro, E, Simoni, G, Ventura, M, Scarpelli, P, Spartera, C, Arena, O, Collice, M, Puttini, M, Romani, F, Santilli, I, Segramora, V, Sterzi, R, Deriu, G, Verlato, F, Cao, Pg, Cieri, Enrico, De Rango, P, Moggi, L, Ricci, S, Antico, A, Spigonardo, F, Malferrari, G, Tusini, N, Vecchiati, E, Cavallaro, A, Kasemi, H, Marino, M, Sbarigia, E, Speziale, F, Zinicola, N, Alò, Fp, Bartolini, M, Carbonari, L, Caporelli, S, Grili Cicilioni, C, Lagalla, G, Ioannidis, G, Pagliariccio, G, Silvestrini, M, Palombo, D, Peinetti, F, Adovasio, R, Chiodo Grandi, F, Mase, G, Zamolo, F, Fregonese, V, Gonano, N, Mozzon, L, Blair, R, Chuen, J, Ferrar, D, Garbowski, M, Hamilton, Mj, Holdaway, C, Muthu, S, Shakibaie, F, Vasudevan, Tm, Kroese, A, Slagsvold, Ce, Dahl, T, Johnsen, Hj, Lange, C, Myhre, Ho, Gniadek, J, Andziak, P, Elwertowski, M, Leszczynski, J, Malek, Ak, Mieszkowski, J, Noszczyk, W, Szostek, M, Toutounchi, S, Correia, C, Pereira, Mc, Akchurin, Rs, Flis, V, Miksic, K, Stirn, B, Tetickovic, E, Cairols, M, Capdevila, Jm, Iborra Ortega, E, Obach, V, Riambau, V, Vidal Barraquer, F, Vila Coll, R, Diaz Vidal, E, Iglesias Negreia JI, Tovar Pardo, A, Iglesias, Rj, Alfageme, Af, Barba Velez, A, Estallo Laliena, L, Garcia Monco JC, Gonzalez, Lr, Corominas, C, Julia, J, Lozano, P, Marti Masso JF, Porta, Rm, Carrera, Ar, Gomez, J, Blomstrand, C, Gelin, J, Holm, J, Karlström, L, Mattsson, E, Bornhov, S, Dahlstrom, J, De Pedis, G, Jensen, Sm, Pärsson, H, Plate, G, Qvarfordt, P, Arvidsson, B, Brattström, L, Forssell, C, Potemkowski, A, Skiöldebrand, C, Stoor, P, Blomqvist, M, Calander, M, Lundgren, F, Almqvist, H, Norgren, L, Norrving, B, Ribbe, E, Thörne, J, Gottsäter, A, Mätzsch, T, Nilsson, Me, Lonsson, M, Stahre, B, Stenberg, B, Konrad, P, Jarl, L, Lundqvist, L, Olofsson, P, Rosfors, S, Swedenborg, J, Takolander, R, Bergqvist, D, Ljungman, C, Kniemeyer, Hw, Widmer, Mk, Kuster, R, Kaiser, R, Nagel, W, Sege, D, Weder, B, De Nie, J, Doelman, J, Yilmaz, N, Buth, J, Stultiens, G, Boiten, J, Boon, A, van der Linden, F, Busman, Dc, Sinnige, Ha, Yo, Ti, de Borst GJ, Eikelboom, Bc, Kappelle, Lj, Moll, F, Dortland, Rw, Westra, Te, Jaber, H, Manaa, J, Meftah, Rb, Nabil, Br, Sraieb, T, Bateman, D, Budd, J, Horrocks, M, Kivela, M, Shaw, L, Walker, R, D'Sa, Aa, Fullerton, K, Hannon, R, Hood, Jm, Lee, B, Mcguigan, K, Morrow, J, Reid, J, Soong, Cv, Simms, M, Baird, R, Campbell, M, Cole, S, Ferguson, It, Lamont, P, Mitchell, D, Sassano, A, Smith, Fc, Blake, K, Kirkpatrick, Pj, Martin, P, Turner, C, Clegg, Jf, Crosley, M, Hall, J, De Cossart, L, Edwards, P, Fletcher, D, Rosser, S, Mccollum, Pt, Davidson, D, Levison, R, Bradbury, Aw, Chalmers, Rt, Dennis, M, Murie, J, Ruckley, Cv, Sandercock, P, Campbell, Wb, Frankel, T, Gardner Thorpe, C, Gutowski, N, Hardie, R, Honan, W, Niblett, P, Peters, A, Ridler, B, Thompson, Jf, Bone, I, Welch, G, Grocott, Ec, Overstall, P, Aldoori, Mi, Dafalla, Be, Bryce, J, Clarke, C, Ming, A, Wilkinson, Ar, Bamford, J, Berridge, D, Scott, J, Abbott, Rj, Naylor, R, Harris, P, Humphrey, P, Adiseshiah, M, Aukett, M, Baker, D, Bishop, Cc, Boutin, A, Brown, M, Burke, P, Burnand, Kg, Colchester, A, Coward, L, Davies, Ah, Espasandin, M, Giddings, Ae, Hamilton, G, Judge, C, Kakkos, S, Mcguiness, C, Morris Vincent, P, Nicolaides, A, Padayachee, Ts, Riordan, H, Sullivan, E, Taylor, P, Thompson, M, Wolfe, Jh, Mccollum, Cn, O'Neill, Pa, Welsh, S, Barnes, J, Cleland, P, Davis, M, Gholkar, A, Jones, R, Jaykishnam, V, Mendelow, Ad, O'Connell, Je, Siddique, Ms, Stansby, G, Vivar, R, Ashley, S, Cosgrove, C, Gibson, J, Wilkins, Dc, Chant, Ad, Frankel, J, Shearman, Cp, Williams, J, Hall, G, Holdsworth, R, Davies, Jn, Mclean, B, Woodburn, Kr, Brown, G, Curley, P, Loizou, L, Chaturvedi, S, Diaz, F, Radak, D, Todorovic, Pr, Kamugasha, D, Baxter, A, Berry, C, Burrett, J, Collins, R, Crowther, J, Davies, C, Farrell, B, Godwin, J, Gray, R, Harwood, C, Hirt, L, Hope, C, Knight, S, Lay, M, Munday, A, Murawska, A, Peto, Cg, Radley, A, Richards, S., Cras, Patrick, van Schil, Paul, et al., Asymptomatic Carotid Surgery Trial (ACST) Collaborative Group, Halliday, A, Harrison, M, Hayter, E, Kong, X, Mansfield, A, Marro, J, Pan, H, Peto, R, Potter, J, Rahimi, K, Rau, A, Robertson, S, Streifler, J, Thomas, D, Adovasio, Roberto, and Asymptomatic Carotid Surgery Trial Collaborative, Group
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Male ,Time Factors ,medicine.medical_treatment ,Kaplan-Meier Estimate ,Carotid endarterectomy ,Aged ,80 and over ,Carotid Stenosis ,Endarterectomy ,Carotid ,Female ,Humans ,Incidence ,Middle Aged ,Primary Prevention ,Stroke ,Treatment Outcome ,Stroke/epidemiology ,law.invention ,Randomized controlled trial ,law ,Aged, 80 and over ,Endarterectomy, Carotid ,endarterectomy ,Carotid Stenosis/mortality ,Incidence (epidemiology) ,Carotid*/mortality ,General Medicine ,Carotid Stenosis | Internal Carotid Artery | Endarterectomy ,medicine.symptom ,medicine.medical_specialty ,Asymptomatic ,Internal medicine ,asymptomatic carotid artery stenosi ,medicine ,asymptomatic carotid artery stenosis ,business.industry ,Carotid Stenosis/complications ,Stroke/prevention & control ,Perioperative ,medicine.disease ,Surgery ,Stenosis ,Human medicine ,business - Abstract
SummaryBackgroundIf carotid artery narrowing remains asymptomatic (ie, has caused no recent stroke or other neurological symptoms), successful carotid endarterectomy (CEA) reduces stroke incidence for some years. We assessed the long-term effects of successful CEA.MethodsBetween 1993 and 2003, 3120 asymptomatic patients from 126 centres in 30 countries were allocated equally, by blinded minimised randomisation, to immediate CEA (median delay 1 month, IQR 0·3–2·5) or to indefinite deferral of any carotid procedure, and were followed up until death or for a median among survivors of 9 years (IQR 6–11). The primary outcomes were perioperative mortality and morbidity (death or stroke within 30 days) and non-perioperative stroke. Kaplan-Meier percentages and logrank p values are from intention-to-treat analyses. This study is registered, number ISRCTN26156392.Findings1560 patients were allocated immediate CEA versus 1560 allocated deferral of any carotid procedure. The proportions operated on while still asymptomatic were 89·7% versus 4·8% at 1 year (and 92·1% vs 16·5% at 5 years). Perioperative risk of stroke or death within 30 days was 3·0% (95% CI 2·4–3·9; 26 non-disabling strokes plus 34 disabling or fatal perioperative events in 1979 CEAs). Excluding perioperative events and non-stroke mortality, stroke risks (immediate vs deferred CEA) were 4·1% versus 10·0% at 5 years (gain 5·9%, 95% CI 4·0–7·8) and 10·8% versus 16·9% at 10 years (gain 6·1%, 2·7–9·4); ratio of stroke incidence rates 0·54, 95% CI 0·43–0·68, p
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- 2010
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25. Analytic self-similar solutions of the Oberbeck–Boussinesq equations
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Barna, I.F., primary and Mátyás, L., additional
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- 2015
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26. Analytic solutions for the three-dimensional compressible Navier–Stokes equation
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Barna, I F, primary and Mátyás, L, additional
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- 2014
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27. Inflation and growth: Explaining a negative effect
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Gillman, M., Harris, Mark, Mátyás, L., Gillman, M., Harris, Mark, and Mátyás, L.
- Abstract
Kormendi and McGuire (1985) document a negative effect of inflation on economic growth for a cross-section of 47 countries during the period 1950-1977. Recent panel evidence such as Barro’s (2001) strengthens the support for such a negative effect. In qualification, Khan and Senhadji (2001), Ghosh and Phillips (1998), and Judson and Orphanides (1996) all find a significant negative inflation-growth effect above a certain “threshold” value of the inflation rate, and no significant effect below the threshold value, without using instrumental variables and with differences found between less and more developed country samples. Further the above threshold negative effect that they find is significantly non-linear whereby the marginal effect is stronger at lower inflation rates than at higher ones; see also Fischer (1993).
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- 2009
28. Pseudo Panel Data
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Verbeek, M.J.C.M., Mátyás, L., Sevestre, P., and Research Group: Econometrics
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- 1996
29. Incomplete panels and selection bias
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Verbeek, M.J.C.M., Nijman, T.E., Mátyás, L., Sevestre, P., Research Group: Econometrics, and Research Group: Finance
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- 1996
30. A Comparative Analysis of Different IV and GMM Estimators of Dynamic Panel Data Models
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Harris, Mark, Mátyás, L., Harris, Mark, and Mátyás, L.
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It is well known that the usual procedures for estimating panel data models are inconsistent in the dynamic setting. A large number of consistent estimators however, have been proposed in the literature. This paper provides a survey of the majority of mainstream estimators, which tend to consist of IV and GMM ones. It also considers a newly proposed extension to the promising Wansbeek-Bekker estimator (Harris & Matyas, 2000). To provide guidance to the applied researcher working on micro-datasets, the small sample performance of these estimators is evaluated using a set of Monte Carlo experiments.
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- 2004
31. Inflation and growth: Explaining a negative effect
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Gillman, M., Harris, Mark, Mátyás, L., Gillman, M., Harris, Mark, and Mátyás, L.
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The paper presents a monetary model of endogenous growth and specifies an econometric model consistent with it. The economic model suggests a negative inflation-growth effect, and one that is stronger at lower levels of inflation. Empirical evaluation of the model is based on a large panel of OECD and APEC member countries over the years 1961-1997. The hypothesized negative inflation effect is found comprehensively for the OECD countries to be significant and, as in the theory, to increase marginally as the inflation rate falls. For APEC countries, the results from using instrumental variables also show significant evidence of a similar behavior. The nature of the inflation-growth profile and differences in this between the regions are interpreted with the credit production technology of the model in a way not possible with a standard cash-only economy.
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- 2004
32. Modelling the Impact of Environmental Regulations on Bilateral Trade Flows: OECD, 1990-1996
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Harris, Mark, Kónya, L., Mátyás, L., Harris, Mark, Kónya, L., and Mátyás, L.
- Abstract
Since the early seventies policy makers and academics alike have been paying increasing attention to the interaction between environmental regulation and foreign trade. The theories and methodologies applicable to this diverse and complex relationship are surveyed among others by Anderson and Blackhurst (1992), Dean (1992), Van Beers and Van den Bergh (1996) and Xing and Kolstad (1996). The specific issues investigated are numerous, ranging from the environmental determinants of trade, through the impact of trade on the environment and the effects of environmental policy on trade, to the substitution or complementarity of trade and environmental policy measures. The focus of this paper is on the relationship between the relative stringency of environmental regulations and international competitiveness. A three-dimensional panel data framework is employed, which allows for both importing and exporting country effects, as well as for time (or business cycle) effects. Even if these additional specific effects are insignificant, the panel data set used is expected to be more reliable and enlightening than a simple cross-sectional data set, since bilateral trade, especially on the lower, two- and three-digit SITC levels, is often prone to strong annual fluctuations. As the analysis shows, as soon as these specific effects are taken into consideration, the relationship between stricter regulations and foreign trade becomes statistically insignificant. This suggests that environmental costs do not have a real impact, either negative or positive, on foreign trade. The paper is structured as follows. The model is briefly described in Section 2. Section 3 discusses the measurements and sources of the data used, with special regard to the strictness of environmental regulations. The empirical findings are summarized in Section 4. Finally, the concluding remarks can be found in Section 5.
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- 2002
33. The Safety and Efficacy of a Paclitaxel-eluting Wrap for Preventing Peripheral Bypass Graft Stenosis: A 2-Year Controlled Randomized Prospective Clinical Study
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Mátyás, L., primary, Berry, M., additional, Menyhei, G., additional, Tamás, L., additional, Acsády, G., additional, Cuypers, P., additional, Halmos, F., additional, de Vries, A.C., additional, Forgacs, V., additional, Ingenito, G., additional, and Avelar, R., additional
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- 2008
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34. Performance of the operational Wansbeek-Bekker estimator for dynamic panel data models
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Harris, Mark, Mátyás, L., Harris, Mark, and Mátyás, L.
- Abstract
Wansbeek and Bekker considered a new estimator for simple dynamic panel data models (where there are no exogenous variables) which involved a complex weighting matrix. An operational variant of this estimator is proposed which is applicable to the more realistic case where there are exogenous variables. Also proposed is an easy-to-compute approximation to the weighting matrix. The performance of this (these) new estimator(s) is examined, revealing very desirable small sample properties in a wide range of situations that the applied researcher is likely to encounter, especially in moderate time series length panels.
- Published
- 2000
35. Spiral modes in the diffusion of a single granular particle on a vibrating surface
- Author
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Klages, R., primary, Barna, I.F., additional, and Mátyás, L., additional
- Published
- 2004
- Full Text
- View/download PDF
36. Growth convergence: some panel data evidence
- Author
-
Lee, M., Longmire, R., Mátyás, L., Harris, Mark, Lee, M., Longmire, R., Mátyás, L., and Harris, Mark
- Abstract
This paper implements a panel data approach of the Solow model to study the phenomenon of growth convergence for 22 OECD countries. It shows that although the derived estimable Solow model is probably underspecified from an econometric point of view, it is still possible to conclude that there is a likely convergence to a steady state rate of about 2-4%.
- Published
- 1998
37. Sarpogrelate, a 5-HT2A receptor antagonist in intermittent claudication. A Phase II European study.
- Author
-
Norgren, L, Jawien, A, Mátyás, L, Rieger, H, Arita, K, and The European MCI-9042 Study Group
- Subjects
INTERMITTENT claudication ,LEG diseases ,THERAPEUTICS ,PLACEBOS ,CARDIOVASCULAR system ,RESEARCH - Abstract
This was a multinational, multicentre, double-blind Phase II study in Europe to evaluate the efficacy and safety of two dose regimens (200 mg bid and 200 mg tid) of sarpogrelate (MCI-9042, 5-HT
2A receptor antagonist) compared to placebo in patients with stable, moderately severe intermittent claudication. Following a single-blind placebo run-in period of 6 weeks, 364 (309 male and 55 female) patients (59.2 ± 8.4 years, mean ± SD) were randomized to receive sarpogrelate 200 mg bid, 200 mg tid or placebo for 24 weeks with a follow-up of 8 weeks. The primary objective was the increase of absolute claudication distance (ACD) at the end of treatment (week 24) compared to placebo. Analysis of covariance (ANCOVA) was performed on the log-transformed percentage of baseline ACD: loge (ACD/baseline). A responder analysis (defined as a ≥50% improvement in ACD) was also performed. There was a marked training/placebo effect on the ACD which persisted up to 16 weeks. At 24 weeks the primary objective did not reach statistical significance (200 mg bid vs placebo, p = 0.225; 200 mg tid vs placebo, p = 0.580). In the responder analysis, 200 mg bid showed a statistically significant difference vs placebo (p = 0.035). In the exploratory analysis with completers (patients completing all treadmill tests), there was a statistical difference in ACD/baseline change for 200 mg bid (p = 0.035) and in the responder analysis for 200 mg tid (p = 0.044) at 24 weeks compared to placebo. Both treatments showed a carry-over effect for ACD during the 8-week follow-up (weeks 28–32). The treatment was well tolerated and no clinically significant safety concerns were reported. In conclusion, the study results confirm that sarpogrelate is well tolerated and although the primary endpoint failed to reach statistical significance, the responder analysis showed an increased absolute walking distance, which makes a further trial warranted, including a larger population, and possibly also a longer treatment period. [ABSTRACT FROM AUTHOR]- Published
- 2006
- Full Text
- View/download PDF
38. Prevention of arterial and venous thrombotic events in symptomatic peripheral arterial disease patients after lower extremity revascularization in the VOYAGER PAD trial: Dual anticoagulant/antiplatelet regimen vs antiplatelet therapy alone.
- Author
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Berkowitz SD, Bauersachs RM, Szarek M, Nehler MR, Debus ES, Patel MR, Anand SS, Capell WH, Hess CN, Hsia J, Leeper NJ, Brasil D, Mátyás L, Diaz R, Brodmann M, Muehlhofer E, Haskell LP, and Bonaca MP
- Subjects
- Anticoagulants therapeutic use, Arteries, Aspirin therapeutic use, Humans, Lower Extremity blood supply, Platelet Aggregation Inhibitors therapeutic use, Rivaroxaban, Endovascular Procedures adverse effects, Peripheral Arterial Disease drug therapy, Peripheral Arterial Disease surgery, Thrombosis etiology, Thrombosis prevention & control
- Abstract
Background: Vascular disease burden after lower extremity revascularization (LER) comprises more than the first event, more vascular beds than the local arteries, and more than one clinical event type., Objectives: Assess total arterial and venous thrombotic burden after LER for symptomatic peripheral artery disease (PAD) and effect of low-dose anticoagulation added to low-dose antiplatelet therapy., Patients/methods: VOYAGER PAD randomized 6564 symptomatic PAD patients undergoing LER to rivaroxaban 2.5 mg twice-daily or placebo on aspirin background. Marginal proportional-hazards models used to generate treatment hazard ratios and associated 95% CIs for first and total events; non-thrombotic deaths treated as competing terminal events. Incidence rates calculated as number of events per 100 patient-years follow-up., Results: Over 2.5 years (median), first and total thrombotic event rates: 7.1 and 10.3 events/100 patient-years, respectively, in placebo group. Two-thirds (925/1372) of total thrombotic events (arterial 95%, venous 5%) were nonfatal first events. Nearly one-third of patients with first event had a second arterial or venous thrombotic event. Rivaroxaban plus aspirin reduced first and total arterial and venous thrombotic events to 5.4 and 7.9 events/100 patient-years, respectively, a reduction in total thrombotic events over aspirin of 23% (HR: 0.77, 95%CI: 0.67-0.89, p = .0005), preventing 6.1 total arterial and venous thrombotic events at 3 years., Conclusions: Assessing total arterial and venous thrombotic events, not just first events, provides more complete information about disease burden and absolute on-treatment impact. Following LER, judicious modulation of more than one coagulation pathway can provide broader benefit than intensifying inhibition of one hemostatic system component., (© 2022 The Authors. Journal of Thrombosis and Haemostasis published by Wiley Periodicals LLC on behalf of International Society on Thrombosis and Haemostasis.)
- Published
- 2022
- Full Text
- View/download PDF
39. Low-dose rivaroxaban plus aspirin in older patients with peripheral artery disease undergoing acute limb revascularization: insights from the VOYAGER PAD trial.
- Author
-
Krantz MJ, Debus SE, Hsia J, Patel MR, Anand SS, Nehler MR, Hess CN, Capell WH, Bracken T, Szarek M, Mátyás L, Krievins DK, Nault P, Stefanov S, Haskell LP, Berkowitz SD, Muehlhofer E, Hiatt WR, Bauersachs RM, and Bonaca MP
- Subjects
- Aged, Aspirin adverse effects, Drug Therapy, Combination, Factor Xa Inhibitors adverse effects, Humans, Platelet Aggregation Inhibitors adverse effects, Rivaroxaban adverse effects, Brain Ischemia, Peripheral Arterial Disease complications, Peripheral Arterial Disease drug therapy, Peripheral Arterial Disease surgery, Stroke drug therapy
- Abstract
Aims: In this secondary analysis of the VOYAGER trial, rivaroxaban 2.5 mg twice/day plus aspirin 100 mg/day was assessed in older adults. Advanced age is associated with elevated bleeding risk and unfavourable net benefit for dual antiplatelet therapy in chronic coronary artery disease. The risk-benefit of low-dose rivaroxaban in patients ≥75 years with peripheral artery disease (PAD) after lower extremity revascularization (LER) has not been described., Methods and Results: The primary endpoint was a composite of acute limb ischaemia, major amputation, myocardial infarction, ischaemic stroke, or cardiovascular death. The principal safety outcome was thrombolysis in myocardial infarction (TIMI) major bleeding analysed by the pre-specified age cut-off of 75 years. Of 6564 patients randomized, 1330 (20%) were >75 years. Absolute 3-year Kaplan-Meier cumulative incidence rates for primary efficacy (23.4% vs. 19.0%) and safety (3.5% vs. 1.5%) endpoints were higher in elderly vs. non-elderly patients. Efficacy of rivaroxaban (P-interaction 0.83) and safety (P-interaction 0.38) was consistent irrespective of age. The combination of intracranial and fatal bleeding was not increased in patients >75 years (2 rivaroxaban vs. 8 placebo). Overall, benefits (absolute risk reduction 3.8%, number needed to treat 26 for the primary endpoint) exceeded risks (absolute risk increase 0.81%, number needed to harm 123 for TIMI major bleeding)., Conclusion: Patients ≥75 years with PAD are at both heightened ischaemic and bleeding risk after LER. No excess harm with respect to major, intracranial or fatal bleeding was seen in older patients yet numerically greater absolute benefits were observed. This suggests that low-dose rivaroxaban combined with aspirin should be considered in PAD after LER regardless of age., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2021. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2021
- Full Text
- View/download PDF
40. Rivaroxaban in Peripheral Artery Disease after Revascularization.
- Author
-
Bonaca MP, Bauersachs RM, Anand SS, Debus ES, Nehler MR, Patel MR, Fanelli F, Capell WH, Diao L, Jaeger N, Hess CN, Pap AF, Kittelson JM, Gudz I, Mátyás L, Krievins DK, Diaz R, Brodmann M, Muehlhofer E, Haskell LP, Berkowitz SD, and Hiatt WR
- Subjects
- Aged, Aspirin adverse effects, Cardiovascular Diseases epidemiology, Cardiovascular Diseases mortality, Cardiovascular Diseases prevention & control, Combined Modality Therapy, Double-Blind Method, Drug Therapy, Combination, Endovascular Procedures, Factor Xa Inhibitors adverse effects, Female, Hemorrhage chemically induced, Hemorrhage epidemiology, Humans, Incidence, Ischemia epidemiology, Kaplan-Meier Estimate, Male, Middle Aged, Peripheral Arterial Disease surgery, Platelet Aggregation Inhibitors adverse effects, Rivaroxaban adverse effects, Aspirin therapeutic use, Factor Xa Inhibitors therapeutic use, Ischemia prevention & control, Lower Extremity blood supply, Peripheral Arterial Disease drug therapy, Platelet Aggregation Inhibitors therapeutic use, Rivaroxaban therapeutic use
- Abstract
Background: Patients with peripheral artery disease who have undergone lower-extremity revascularization are at high risk for major adverse limb and cardiovascular events. The efficacy and safety of rivaroxaban in this context are uncertain., Methods: In a double-blind trial, patients with peripheral artery disease who had undergone revascularization were randomly assigned to receive rivaroxaban (2.5 mg twice daily) plus aspirin or placebo plus aspirin. The primary efficacy outcome was a composite of acute limb ischemia, major amputation for vascular causes, myocardial infarction, ischemic stroke, or death from cardiovascular causes. The principal safety outcome was major bleeding, defined according to the Thrombolysis in Myocardial Infarction (TIMI) classification; major bleeding as defined by the International Society on Thrombosis and Haemostasis (ISTH) was a secondary safety outcome., Results: A total of 6564 patients underwent randomization; 3286 were assigned to the rivaroxaban group, and 3278 were assigned to the placebo group. The primary efficacy outcome occurred in 508 patients in the rivaroxaban group and in 584 in the placebo group; the Kaplan-Meier estimates of the incidence at 3 years were 17.3% and 19.9%, respectively (hazard ratio, 0.85, 95% confidence interval [CI], 0.76 to 0.96; P = 0.009). TIMI major bleeding occurred in 62 patients in the rivaroxaban group and in 44 patients in the placebo group (2.65% and 1.87%; hazard ratio, 1.43; 95% CI, 0.97 to 2.10; P = 0.07). ISTH major bleeding occurred in 140 patients in the rivaroxaban group, as compared with 100 patients in the placebo group (5.94% and 4.06%; hazard ratio, 1.42; 95% CI, 1.10 to 1.84; P = 0.007)., Conclusions: In patients with peripheral artery disease who had undergone lower-extremity revascularization, rivaroxaban at a dose of 2.5 mg twice daily plus aspirin was associated with a significantly lower incidence of the composite outcome of acute limb ischemia, major amputation for vascular causes, myocardial infarction, ischemic stroke, or death from cardiovascular causes than aspirin alone. The incidence of TIMI major bleeding did not differ significantly between the groups. The incidence of ISTH major bleeding was significantly higher with rivaroxaban and aspirin than with aspirin alone. (Funded by Bayer and Janssen Pharmaceuticals; VOYAGER PAD ClinicalTrials.gov number, NCT02504216.)., (Copyright © 2020 Massachusetts Medical Society.)
- Published
- 2020
- Full Text
- View/download PDF
41. A prospective, single-blind, randomized, phase III study to evaluate the safety and efficacy of Fibrin Sealant Grifols as an adjunct to hemostasis compared with manual compression in vascular surgery.
- Author
-
Nenezić D, Ayguasanosa J, Menyhei G, Tamás H, Mátyás L, Muluk S, Courtney K, Ibáñez J, and Chen J
- Subjects
- Adult, Aged, Aged, 80 and over, Blood Loss, Surgical statistics & numerical data, Female, Fibrin Tissue Adhesive adverse effects, Humans, Male, Middle Aged, Pressure, Prospective Studies, Single-Blind Method, Treatment Outcome, Young Adult, Blood Loss, Surgical prevention & control, Fibrin Tissue Adhesive administration & dosage, Hemostasis, Surgical methods, Vascular Surgical Procedures adverse effects
- Abstract
Objective: New formulations and applications of hemostatic adjuncts such as fibrin sealant (FS) to support local hemostasis and sutures continue to be developed. In a pivotal, confirmatory, controlled, prospective, single-blinded, randomized, multicenter phase III clinical trial, the efficacy and safety of FS Grifols during vascular surgeries were evaluated., Methods: Patients undergoing a nonemergency, open, peripheral vascular surgical procedure with moderate arterial bleeding were recruited. In an initial preliminary part of the study, all patients were treated with FS Grifols. In a subsequent primary part, patients were randomized (2:1) to FS Grifols or manual compression (MC). The primary efficacy end point was the proportion of the primary part patients achieving hemostasis by 4 minutes after the start of treatment. Cumulative proportion and time to hemostasis were secondary efficacy end points. Safety end points (in pooled preliminary and primary parts) included adverse events (AEs), vital signs, physical assessments, clinical laboratory tests, viral markers, and immunogenicity., Results: The primary efficacy end point was met by 76.1% of patients (83/109) for the FS Grifols group versus 22.8% of patients (13/57) for the MC group (P < .001). The cumulative proportion of patients at 5, 7, and 10 minutes was 80.7%, 84.4%, and 88.1%, respectively, in the FS Grifols treatment group, and 28.1%, 35.1%, and 45.6% in the MC treatment group (P < .001). The median time to hemostasis was shorter in the FS Grifols group (4 minutes vs ≥10 minutes in the MC group; P < .001). The nature of AEs reported were those expected in the study patient profile. The percentage of patients experiencing treatment-emergent AEs were similar in both the FS Grifols (pooled n = 59 + 109) and MC groups (81.0% and 77.2%, respectively), most recurrent being procedural pain (34.5% and 36.8%, respectively) and pyrexia (11.3% and 10.5%, respectively)., Conclusions: FS Grifols was superior in efficacy and similar in safety to MC as an adjunct local hemostatic agent in patients undergoing open vascular surgeries., (Copyright © 2019 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
42. Sarpogrelate, a 5-hT2A receptor antagonist in intermittent claudication. A phase II European study.
- Author
-
Norgren L, Jawien A, Mátyás L, Riegerd H, and Arita K
- Subjects
- Adult, Aged, Double-Blind Method, Europe, Exercise Test, Female, Humans, Intermittent Claudication etiology, Intermittent Claudication metabolism, Male, Middle Aged, Receptor, Serotonin, 5-HT2A metabolism, Serotonin Antagonists pharmacology, Succinates pharmacology, Treatment Outcome, Walking, Intermittent Claudication drug therapy, Lower Extremity blood supply, Serotonin 5-HT2 Receptor Antagonists, Serotonin Antagonists therapeutic use, Succinates therapeutic use
- Abstract
This was a multinational, multicentre, double-blind Phase II study in Europe to evaluate the efficacy and safety of two dose regimens (200 mg bid and 200 mg tid) of sarpogrelate (MCI-9042, 5-HT2A receptor antagonist) compared to placebo in patients with stable, moderately severe intermittent claudication. Following a single-blind placebo run-in period of 6 weeks, 364 (309 male and 55 female) patients (59.2 +/- 8.4 years, mean +/- SD) were randomized to receive sarpogrelate 200 mg bid, 200 mg tid or placebo for 24 weeks with a follow-up of 8 weeks. The primary objective was the increase of absolute claudication distance (ACD) at the end of treatment (week 24) compared to placebo. Analysis of covariance (ANCOVA) was performed on the log-transformed percentage of baseline ACD: loge(ACD/baseline). A responder analysis (defined as a > or = 50% improvement in ACD) was also performed. There was a marked training/placebo effect on the ACD which persisted up to 16 weeks. At 24 weeks the primary objective did not reach statistical significance (200mg bid vs placebo, p = 0.225; 200mg tid vs placebo, p = 0.580). In the responder analysis, 200 mg bid showed a statistically significant difference vs placebo (p = 0.035). In the exploratory analysis with completers (patients completing all treadmill tests), there was a statistical difference in ACD/baseline change for 200 mg bid (p = 0.035) and in the responder analysis for 200 mg tid (p = 0.044) at 24 weeks compared to placebo. Both treatments showed a carry-over effect for ACD during the 8-week follow-up (weeks 28-32). The treatment was well tolerated and no clinically significant safety concerns were reported. In conclusion, the study results confirm that sarpogrelate is well tolerated and although the primary endpoint failed to reach statistical significance, the responder analysis showed an increased absolute walking distance, which makes a further trial warranted, including a larger population, and possibly also a longer treatment period.
- Published
- 2006
- Full Text
- View/download PDF
43. Entropy production in diffusion-reaction systems: the reactive random Lorentz gas.
- Author
-
Mátyás L and Gaspard P
- Abstract
We report the study of a random Lorentz gas with a reaction of isomerization A<==>B between two colors of moving particles elastically bouncing on hard disks. The reaction occurs when the moving particles collide on catalytic disks, which constitute a fraction of all the disks. Under dilute-gas conditions, the reaction-diffusion process is ruled by two coupled Boltzmann-Lorentz equations for the distribution functions of the colors. The macroscopic reaction-diffusion equations with cross-diffusion terms induced by the chemical reaction are derived from the kinetic equations. We use an H theorem of the kinetic theory in order to derive a macroscopic entropy depending on the gradients of color densities and which has a non-negative entropy production in agreement with the second law of thermodynamics.
- Published
- 2005
- Full Text
- View/download PDF
44. Coarse-grained entropy and information dimension of dynamical systems: The driven Lorentz gas.
- Author
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Mátyás L, Tél T, and Vollmer J
- Abstract
We study the resolution dependence of the steady-state saturation values of coarse-grained entropies characterizing general dynamical systems. For dissipative maps they are proportional to the information codimension of the chaotic attractor. Thus, they provide a highly accurate method for determining the information dimension and related characteristics of the dynamical system. This general result is demonstrated for the field-driven Lorentz gas. In the discussion, we take the results on the resolution dependence of the entropy as the starting point to revisit different approaches to define thermodynamic entropy production for transport processes in dynamical systems, and discuss the role of local equilibrium in this enterprise.
- Published
- 2004
- Full Text
- View/download PDF
45. Multibaker map for shear flow and viscous heating.
- Author
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Mátyás L, Tél T, and Vollmer J
- Abstract
A consistent description of shear flow and the accompanying viscous heating as well as the associated entropy balance is given in the framework of a deterministic dynamical system. The laminar shear flow is modeled by a Hamiltonian multibaker map which drives velocity and temperature fields. In the appropriate macroscopic limit one recovers the Navier-Stokes and heat conduction equations along with the associated entropy balance. This indicates that results of nonequilibrium thermodynamics can be described by means of an abstract, sufficiently chaotic, and mixing dynamics. A thermostating algorithm can also be incorporated into this framework.
- Published
- 2001
- Full Text
- View/download PDF
46. [A new method for the management of perforated veins in the lower extremities].
- Author
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Bende J, Mátyás L, Virág B, Hajdu J, Helembai L, Medgyesy G, and Senánszky M
- Subjects
- Endoscopes, Leg blood supply, Leg Ulcer surgery, Ligation instrumentation, Ligation methods, Surgical Instruments, Thrombophlebitis surgery, Venous Insufficiency surgery, Leg Ulcer etiology, Thrombophlebitis complications, Venous Insufficiency complications
- Abstract
Elimination of incompetent perforating veins is the effective therapeutic method in the treatment of lower leg ulceration and trophic skin disorders associated with chronic venous insufficiency. The subfascial endoscopic ligation is a new surgical method to treat patients with incompetent perforating veins. 19 patients with severe chronic venous insufficiency or protracted venous ulceration of lower leg were treated. Through an incision of the skin the proximal 1/3 of the lower leg-far away from the dermatosclerotic area-an endoscope is inserted after which the perforating veins are ligated by clips under direct vision. The method is recommended due to its reduced invasiveness and the fair results.
- Published
- 1998
47. [Successful treatment of injuries involving the common carotid].
- Author
-
Mátyás L and Gyurkó G
- Subjects
- Accidents, Traffic, Adult, Blood Vessel Prosthesis, Carotid Arteries surgery, Female, Humans, Wounds, Penetrating surgery, Carotid Artery Injuries
- Published
- 1984
48. SEASONAL VARIATIONS OF SODIUM AND POTASSIUM CONCENTRATIONS IN DIFFERENT PARTS OF THE FROG MYOCARDIUM.
- Author
-
Harza T and Mátyás L
- Abstract
Sodium and potassium concentrations in different parts of the frog heart (sinus venosus, atrium and ventricle) were investigated at various seasons of the year. The sodium concentration showed a marked periodicity in all three parts of the heart: minimum in winter, maximum in summer. Potassium concentration showed no seasonal variations, except for reduction in potassium concentration of the ventricle in the second half of the year. The experimental results for sodium can be fitted by a sine curve, the differences between minimum (in winter) and maximum (in summer) representing 46.4% (for sinus venosus), 30.4% (atrium) and 34.0% (ventricle) of the spring-autumn values. Variation in the electrolyte concentration could be explained by changes in salt. and water metabolism induced by fluctuations in the temperature on one hand, and by the removal of the animals from their natural environment on the other.
- Published
- 1976
- Full Text
- View/download PDF
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