31 research outputs found

    Lax-Phillips scattering theory for PT-symmetric \rho-perturbed operators

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    The S-matrices corresponding to PT-symmetric \rho-perturbed operators are defined and calculated by means of an approach based on an operator-theoretical interpretation of the Lax-Phillips scattering theory

    On elements of the Lax-Phillips scattering scheme for PT-symmetric operators

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    Generalized PT-symmetric operators acting an a Hilbert space H\mathfrak{H} are defined and investigated. The case of PT-symmetric extensions of a symmetric operator SS is investigated in detail. The possible application of the Lax-Phillips scattering methods to the investigation of PT-symmetric operators is illustrated by considering the case of 0-perturbed operators

    JJ-self-adjoint operators with C\mathcal{C}-symmetries: extension theory approach

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    A well known tool in conventional (von Neumann) quantum mechanics is the self-adjoint extension technique for symmetric operators. It is used, e.g., for the construction of Dirac-Hermitian Hamiltonians with point-interaction potentials. Here we reshape this technique to allow for the construction of pseudo-Hermitian (JJ-self-adjoint) Hamiltonians with complex point-interactions. We demonstrate that the resulting Hamiltonians are bijectively related with so called hypermaximal neutral subspaces of the defect Krein space of the symmetric operator. This symmetric operator is allowed to have arbitrary but equal deficiency indices . General properties of the $\cC$ operators for these Hamiltonians are derived. A detailed study of $\cC$-operator parametrizations and Krein type resolvent formulas is provided for $J$-self-adjoint extensions of symmetric operators with deficiency indices . The technique is exemplified on 1D pseudo-Hermitian Schr\"odinger and Dirac Hamiltonians with complex point-interaction potentials

    On the similarity of Sturm-Liouville operators with non-Hermitian boundary conditions to self-adjoint and normal operators

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    We consider one-dimensional Schroedinger-type operators in a bounded interval with non-self-adjoint Robin-type boundary conditions. It is well known that such operators are generically conjugate to normal operators via a similarity transformation. Motivated by recent interests in quasi-Hermitian Hamiltonians in quantum mechanics, we study properties of the transformations in detail. We show that they can be expressed as the sum of the identity and an integral Hilbert-Schmidt operator. In the case of parity and time reversal boundary conditions, we establish closed integral-type formulae for the similarity transformations, derive the similar self-adjoint operator and also find the associated "charge conjugation" operator, which plays the role of fundamental symmetry in a Krein-space reformulation of the problem.Comment: 27 page

    Physical-mechanical image of the cell surface on the base of AFM data in contact mode

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    Π˜Π·ΡƒΡ‡Π΅Π½Ρ‹ Ρ„ΠΈΠ·ΠΈΠΊΠΎ-мСханичСскиС ΠΎΠ±Ρ€Π°Π·Ρ‹ повСрхности фибробластов ΠΈ Ρ€Π°ΠΊΠΎΠ²Ρ‹Ρ… ΡΠΏΠΈΡ‚Π΅Π»ΠΈΠ°Π»ΡŒΠ½Ρ‹Ρ… ΠΊΠ»Π΅Ρ‚ΠΎΠΊ Ρ‡Π΅Π»ΠΎΠ²Π΅ΠΊΠ°, созданныС Π½Π° основС Π΄Π°Π½Π½Ρ‹Ρ… Π°Ρ‚ΠΎΠΌΠ½ΠΎ-силовой микроскопии Π² ΠΊΠΎΠ½Ρ‚Π°ΠΊΡ‚Π½ΠΎΠΌ Ρ€Π΅ΠΆΠΈΠΌΠ΅ ΠΏΠΎ срСдним значСниям сил трСния, упругости ΠΈ Π°Π΄Π³Π΅Π·ΠΈΠΈ ΠΈ ΠΏΠ°Ρ€Π°ΠΌΠ΅Ρ‚Ρ€ΠΎΠ² пространствСнного распрСдСлСния мСханичСских свойств ΠΊΠ»Π΅Ρ‚ΠΎΡ‡Π½ΠΎΠΉ повСрхности.Physical-mechanical images of the cell surface of human fibroblasts and cancerous epithelial cells that were formed using the average values of the parameters of friction, elastic and adhesive forces and the spatial distribution parameters of mechanical properties obtained by atomic force microscopy in contact mode were studied

    ИсслСдованиС влияния Ρ‚Π΅ΠΌΠΏΠ΅Ρ€Π°Ρ‚ΡƒΡ€Ρ‹ ΠΊΡƒΠ»ΡŒΡ‚ΠΈΠ²ΠΈΡ€ΠΎΠ²Π°Π½ΠΈΡ Π½Π° ΠΌΠΎΡ€Ρ„ΠΎΠ»ΠΎΠ³ΠΈΡŽ, мСханичСскиС ΠΈ Π°Π΄Π³Π΅Π·ΠΈΠΎΠ½Π½Ρ‹Π΅ свойства Ρ€Π°ΠΊΠΎΠ²Ρ‹Ρ… ΠΊΠ»Π΅Ρ‚ΠΎΠΊ Π»Π΅Π³ΠΊΠΈΡ… Ρ‡Π΅Π»ΠΎΠ²Π΅ΠΊΠ° Π»ΠΈΠ½ΠΈΠΈ А549

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    The results of study the effect of temperature on the culture surface topography and mechanical properties of human lung cancer cell line A549 by atomic force microscopy are presented. It is shown that lowering the temperature of cultivation does not lead to significant changes in the mechanical properties of A549 cells, but the cells under the influence of low temperatures tend to increase the adhesive force between the probe tip to the membrane surface.ΠŸΡ€Π΅Π΄ΡΡ‚Π°Π²Π»Π΅Π½Ρ‹ Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Ρ‹ исслСдования ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠΌ Π°Ρ‚ΠΎΠΌΠ½ΠΎ-силовой микроскопии влияния Ρ‚Π΅ΠΌΠΏΠ΅Ρ€Π°Ρ‚ΡƒΡ€Ρ‹ ΠΊΡƒΠ»ΡŒΡ‚ΠΈΠ²ΠΈΡ€ΠΎΠ²Π°Π½ΠΈΡ Π½Π° Ρ‚ΠΎΠΏΠΎΠ³Ρ€Π°Ρ„ΠΈΡŽ повСрхности ΠΈ мСханичСскиС свойства Ρ€Π°ΠΊΠΎΠ²Ρ‹Ρ… ΠΊΠ»Π΅Ρ‚ΠΎΠΊ Π»Π΅Π³ΠΊΠΈΡ… Ρ‡Π΅Π»ΠΎΠ²Π΅ΠΊΠ° Π»ΠΈΠ½ΠΈΠΈ А549. Показано, Ρ‡Ρ‚ΠΎ ΠΏΠΎΠ½ΠΈΠΆΠ΅Π½ΠΈΠ΅ Ρ‚Π΅ΠΌΠΏΠ΅Ρ€Π°Ρ‚ΡƒΡ€Ρ‹ ΠΊΡƒΠ»ΡŒΡ‚ΠΈΠ²ΠΈΡ€ΠΎΠ²Π°Π½ΠΈΡ Π½Π΅ ΠΏΡ€ΠΈΠ²ΠΎΠ΄ΠΈΡ‚ ΠΊ достовСрным измСнСниям мСханичСских свойств Π΄Π°Π½Π½Ρ‹Ρ… ΠΊΠ»Π΅Ρ‚ΠΎΠΊ, ΠΎΠ΄Π½Π°ΠΊΠΎ ΡƒΠ²Π΅Π»ΠΈΡ‡ΠΈΠ²Π°Π΅Ρ‚ силу Π°Π΄Π³Π΅Π·ΠΈΠΈ острия Π·ΠΎΠ½Π΄Π° ΠΊ повСрхности ΠΌΠ΅ΠΌΠ±Ρ€Π°Π½Ρ‹

    ИсслСдованиС ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠΌ Π°Ρ‚ΠΎΠΌΠ½ΠΎ-силовой микроскопии влияния наночастиц Π½Π° структурныС ΠΈ мСханичСскиС свойства ΠΊΠ»Π΅Ρ‚ΠΎΠΊ ΠΏΠΎΡ‡ΠΊΠΈ Π±Ρ‹ΠΊΠ° Π»ΠΈΠ½ΠΈΠΈ MDBK

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    The effect of copper and silver nanoparticles Cu+Ag, silver nitrite AgNO3 and zinc oxide ZnO on morphology and mechanical properties of immunocompetent cells bovine kidney line MDBK is investigated by atomic force microscopy. The results of calculation of the local elastic modulus, strength, surface cell adhesion, adhesion work, and the three-dimensional image analysis of cells in control and after incubation with the nanoparticles bioelements for 20 min are presented.ΠœΠ΅Ρ‚ΠΎΠ΄ΠΎΠΌ Π°Ρ‚ΠΎΠΌΠ½ΠΎ-силовой микроскопии (АБМ) исслСдовано влияниС наночастиц ΠΌΠ΅Π΄ΠΈ ΠΈ сСрСбра Cu+Ag, Π½ΠΈΡ‚Ρ€ΠΈΡ‚Π° сСрСбра AgNO3 ΠΈ оксида Ρ†ΠΈΠ½ΠΊΠ° ZnO Π½Π° ΠΌΠΎΡ€Ρ„ΠΎΠ»ΠΎΠ³ΠΈΡŽ ΠΈ мСханичСскиС свойства ΠΈΠΌΠΌΡƒΠ½ΠΎΠΊΠΎΠΌΠΏΠ΅Ρ‚Π΅Π½Ρ‚Π½Ρ‹Ρ… ΠΊΠ»Π΅Ρ‚ΠΎΠΊ ΠΏΠΎΡ‡ΠΊΠΈ Π±Ρ‹ΠΊΠ° Π»ΠΈΠ½ΠΈΠΈ MDBK. ΠŸΡ€Π΅Π΄ΡΡ‚Π°Π²Π»Π΅Π½Ρ‹ Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Ρ‹ расчСтов локального модуля упругости, силы повСрхностной Π°Π΄Π³Π΅Π·ΠΈΠΈ ΠΊΠ»Π΅Ρ‚ΠΎΠΊ, Ρ€Π°Π±ΠΎΡ‚Ρ‹ Π°Π΄Π³Π΅Π·ΠΈΠΈ, Π° Ρ‚Π°ΠΊΠΆΠ΅ Π°Π½Π°Π»ΠΈΠ·Π° Ρ‚Ρ€Π΅Ρ…ΠΌΠ΅Ρ€Π½Ρ‹Ρ… ΠΈΠ·ΠΎΠ±Ρ€Π°ΠΆΠ΅Π½ΠΈΠΉ ΠΊΠ»Π΅Ρ‚ΠΎΠΊ Π² ΠΊΠΎΠ½Ρ‚Ρ€ΠΎΠ»Π΅ ΠΈ послС ΠΈΠ½ΠΊΡƒΠ±Π°Ρ†ΠΈΠΈ с наночастицами биоэлСмСнтов Π² Ρ‚Π΅Ρ‡Π΅Π½ΠΈΠ΅ 20 ΠΌΠΈΠ½

    LEFT VENTRICLE TORSION IN AN IDIOPATHIC HIS LEFT BUNDLE BRANCH BLOCK

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    The role of left His bundle branch block (LBBB) in normal systolic function of the left ventricle (LV) remains under investigated for the global deformation and torsion.Aim. To investigate on the global deformity of the LV in longitudinal direction by circumference, and its torsion, in patients with idiopathic LBBB with saved LV ejection fraction (EF).Material and methods. Totally, 50 persons with idiopathic LBBB studied, with the mean duration of QRS 153Β±24,5 ms. Comparison group included 18 persons with no LBBB. All patients underwent echocardiography (Echo) with assessment of intracardiac hemodynamics, deformity measurement by Speckle tracking imaging, with evaluation of torsion and rotation dynamics of the LV. Results. There were no significant differences in idiopathic LBBB group comparing to the controls, by the value of end-diastolic volume (respectively, 110,5Β±33,5 mL vs 95,3Β±23,5 mL, Ρ€=0,1) and EF LV (61,3Β±9,5% vs 64,4Β±9,4%, Ρ€=0,2). In idiopathic LBBB group comparing to controls, there was decrease of global LV deformation in longitudinal direction (respectively, -14,6Β±3,98% vs -8,4Β±3,10%, Ρ€=0,0006) and by circumference at basal segments (-7,02Β±4,40)% vs -10,6Β±4,18%, Ρ€=0,0075). It was found that in idiopathic LBBB there is disordered rotation at basal segments level (-2,95Β±4,36ΒΊ vs -6,10Β±3,01ΒΊ, Ρ€=0,019) and the torsion of LV as well (7,52Β±5,48ΒΊ vs 13,1Β±5,18ΒΊ, Ρ€=0,001).Conclusion. Disordered conduction in LBBB is followed by impaired rotation and torsion, regardless of the saved systolic function

    Heart failure with preserved ejection fraction: the role of diastolic stress test in diagnostic algorithms

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    Heart failure (HF) with preserved ejection fraction (HFpEF) is currently the most common type of this condition, especially among elderly patients. Despite the preserved left ventricular (LV) and a moderate increase in natriuretic peptide, patientsΒ  with HFpEF have the same out-of-hospital mortality as those with HF with reduced ejection fraction (HFrEF). Diagnosis of HFpEF is difficult due to nonspecific symptoms, expensive blood tests, and questionable rest echocardiographic data on diastolic function. In addition, the reason for poor diagnosis of HfpEF in clinical practice may be old age and comorbidities, which can also cause nonspecific symptoms of moderate chronic shortness of breath, weakness, and palpitations. The consequence is the detection of HFpEF only in every fourth patient with an acute or chronic heart failure. The use of simplified clinical diagnostic protocols along with a non-invasive ultrasound stress test can help overcome the existing problems in the diagnosis of HFpEF
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