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Journal of Geriatric Cardiology 2018年第1期15卷 66-75页

作者： Manolis Vavuranakis Konstantinos Kalogeras Angelos Michail Kolokathis Dimitrios Vrachatis Nikolaos Magkoutis Gerasimos Siasos euaggelos oikonomou Maria Kariori Theodoros Papaioannou Maria Lavda Carmen Moldovan Ourania Katsarou Dimitrios Tousoulis The First Department of Cardiology Hippokration Hospital Medical School National & Kapodistrian University of Athens Ilioupoli Greece

Transcatheter aortic valve implantation （TAVI） carries a significant thromboembolic and concomitant bleeding risk, not only during the procedure but also during the periprocedural period. Many issues concerning optimal antithrombotic therapy after TAVI are still under debate. In the present review, we aimed to identify all relevant studies evaluating antithrombotic therapeutic strategies in relation to clinical outcomes after the procedure. Four randomized control trials （RCT） were identified analyzing the post-TAVI antithrombotic strategy with all of them utilizing aspirin lifelong plus clopidogrel for 3-6 months. Seventeen registries have been identified, with a wide variance among them regarding baseline characteristics, while concerning antiplatelet therapy, clopidogrel duration was ranging from 3-12 months. Four non-randomized trials were identified, comparing single vs. dual antiplatelet therapy after TAVI, in respect of investigating thromboembolic outcome events over bleeding complications. Finally, limited data from a single RCT and a retrospective study exist with regards to anticoagulant treatment during the procedure and the optimal antithrombotic therapy when concomitant atrial fibrillation. In conclusion, due to the high risk and frailty of the treated population, antithrombotic therapy after TAVI should be carefully evaluated. Diminishing ischaemic and bleeding complications remains the main challenge in these patients with further studies to be needed in this field.

关键词： Antiplatelets Antithrombotic Bleeding Stroke Transcatheter aortic valve implantation

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Comparing the behavior of orbits in different 3D dynamical models for elliptical galaxies

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Research in Astronomy and Astrophysics 2012年第4期12卷 383-399页

作者： euaggelos E.Zotos Department of Physics Section of Astrophysics Astronomy and Mechanics Aristotle University of Thessaloniki 541 24 Thessaloniki Greece

We study the behavior of orbits in two different galactic dynamical models, describing the motion in the central parts of a triaxial elliptical galaxy with a dense nucleus. Numerical experiments show that both models display regular motion together with extended chaotic regions. A detailed investigation of the properties of motion is made for the 2D and 3D Hamiltonian systems, using a number of different dynamical parameters, such as the Poincare′ surface of a section, the maximal Lyapunov Characteristic Exponent, the S（c） spectrum, the S（w） spectrum and the P （f ） indicator. The numerical calculations suggest that the properties of motion in both potentials are very similar. Our results show that one may use different kinds of gravitational potentials in order to describe the motion in triaxial galaxies while obtaining quantitatively similar results.

关键词： galaxies kinematics and dynamics-- galaxies elliptical

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Order and chaos in a galactic model with a strong nuclear bar

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Research in Astronomy and Astrophysics 2012年第5期12卷 500-512页

作者： euaggelos E. Zotos Department of Physics Section of AstrophysicsAstronomy and MechanicsAristotle University of Thessaloniki 541 24ThessalonikiGreece

We use a composite gravitational galactic model consisting of a disk, a halo, a massive nucleus and a strong nuclear bar, in order to study the connections between global and local parameters in a realistic dynamical system. The local model is constructed from a two-dimensional perturbed harmonic oscillator and can be derived by expanding the global model in the vicinity of the central stable Lagrange equilibrium point. The frequencies of oscillations are not arbitrary, but they are connected with all the parameters involved with the global model. Moreover, the value of the local energy is also connected with the value of the global energy. Low and high energy stars in the global model display chaotic motion. Comparison with previous research reveals that the presence of the massive nucleus is responsible for the chaotic motion of the low energy stars. In the local motion, the low energy stars show interesting resonance phenomena, but the chaotic motion, if any, is negligible. On the contrary, the high energy stars do not show bounded motion in the local model. This is an indication of particular activity near the center of galaxies possessing massive nuclei.

关键词： galaxies kinematics and dynamics

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Determining the type of orbits in the central regions of barred galaxies

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Research in Astronomy and Astrophysics 2016年第2期16卷 45-62页

作者： euaggelos E.Zotos Nicolaos D.Caranicolas Department of Physics Section of AstrophysicsAstronomy and MechanicsAristotle University of ThessalonikiGR-54124

We use a simple dynamical model which consists of a harmonic oscillator and a spherical com- ponent, in order to investigate the regular or chaotic character of orbits in a barred galaxy with a central spherically symmetric nucleus. Our aim is to explore how the basic parameters of the galactic system in- fluence the nature of orbits, by computing in each case the percentage of chaotic orbits, as well as the percentages of different types of regular orbits. We also give emphasis to the types of regular orbits that support either the formation of nuclear rings or the barred structure of the galaxy. We provide evidence that the traditional xl orbital family does not always dominate in barred galaxy models since we found several other types of resonant orbits which can also support the barred structure. We also found that sparse enough nuclei, fast rotating bars and high energy models can support the galactic bars. On the other hand, weak bars, dense central nuclei, slowly rotating bars and low energy models favor the formation of nuclear rings. We also compare our results with previous related work.

关键词： galaxies kinematics and dynamics

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Dark halos acting as chaos controllers in asymmetric triaxial galaxy models

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Research in Astronomy and Astrophysics 2011年第7期11卷 811-823页

作者： Nicolaos D.Caranicolas euaggelos E.Zotos Department of Physics Section of AstrophysicsAstronomy and MechanicsAristotle University of Thessaloniki 541 24ThessalonikiGreece

We study the regular or chaotic character of orbits in a 3D dynamical model,describing a triaxial galaxy surrounded by a spherical dark halo *** numerical experiments suggest that the percentage of chaotic orbits decreases exponentially as the mass of the dark halo increases.A linear increase of the percentage of the chaotic orbits was observed as the scale length of the halo component increases. In order to distinguish between regular and chaotic motion,we chose to use the total angular momentum Ltot of the 3D orbits as a new *** with other,previously used,dynamical indicators,such as the Lyapunov Characteristic Exponent or the P（f） spectral method,shows that the Ltot indicator gives very fast and reliable results for characterizing the nature of orbits in galactic dynamical models.

关键词： galaxies:kinematics and dynamics—dynamical indicators

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The nature of orbits in a prolate elliptical galaxy model with a bulge and a dense nucleus

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Research in Astronomy and Astrophysics 2011年第12期11卷 1449-1456页

作者： Nicolaos D.Caranicolas euaggelos E.Zotos Department of Physics Section of AstrophysicsAstronomy and MechanicsAristotle University of Thessaloniki 541 24ThessalonikiGreece

We study the transition from regular to chaotic motion in a prolate elliptical galaxy dynamical model with a bulge and a dense nucleus. Our numerical investigation shows that stars with angular momentum Lz less than or equal to a critical value Lzc, moving near the galactic plane, are scattered to higher z, when reaching the central region of the galaxy, thus displaying chaotic motion. An inverse square law relationship was found to exist between the radius of the bulge and the critical value Lzc of the angular momentum. On the other hand, a linear relationship exists between the mass of the nucleus and Lzc. The numerically obtained results are explained using theoretical arguments. Our study shows that there are connections between regular or chaotic motion and the physical parameters of the system, such as the star＇s angular momentum and mass, the scale length of the nucleus and the radius of the bulge. The results are compared with the outcomes of previous work.

关键词： galaxies: kinematics and dynamics

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The influence of postoperative infection in survival of patients with high-grade gliomas

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Neuroimmunology and Neuroinflammation 2015年第1期2卷 18-20页

作者： George A.Alexiou Amalia Kallinteri euaggelos Michos Panagiota Zagorianakou Efthalia Priavali Dimitrios Pachatouridis Stamatina Levidiotou Spyridon Voulgaris Department of Neurosurgery Medical SchoolUniversity of Ioannina45110 IoanninaGreece Department of Microbiology Medical SchoolUniversity of Ioannina45110 IoanninaGreece

High‑grade gliomas are the most common type of brain *** these,glioblastoma account for 60-70%and despite treatment carries a dismal *** surgical site infection has been associated with prolonged ***,we present a case of glioblastoma and a case of anaplastic oligoastrocytoma that developed postoperative infection of the surgical site and had prolonged survival.A thorough literature review is also presented.

关键词： Glioblastoma high‑grade glioma infection survival

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