2,245 research outputs found
Squeezed states of damped oscillator chain
The Caldirola-Kanai model of one-dimensional damped oscillator is extended to the chain of coupled parametric oscillators with damping. The correlated and squeezed states for the chain of coupled parametric oscillators with damping are constructed. Based on the concept of the integrals of motion, it is demonstrated how squeezing phenomenon arises due to parametric excitation
Damped Oscillator with Delta-Kicked Frequency
Exact solutions of the Schrodinger equation for quantum damped oscillator subject to frequency delta-kick describing squeezed states are obtained. The cases of strong, intermediate, and weak damping are investigated
Adaptive respiratory response of rat pancreatic acinar cells to mitochondrial membrane depolarization
The dependence of uncoupled respiratory capacity of intact pancreatic acini on oxidative substrate supply and functional cell state has not yet been studied in detail. In this study, the respiratory responses of isolated pancreatic acini to FCCP were measured with Clark electrode and mitochondrial membrane potential was assessed with rhodamine123 fluorescence. The response of acini to FCCP was characterized with maximal uncoupled respiration rate, optimal FCCP concentration, respiration acceleration and deceleration. Maximal uncoupled respiration rate substantially increased upon the oxidation of glucose + glutamine (3.03 ± 0.54 r.u.), glucose + glutamine + pyruvate (2.82 ± 0.51 r.u.), glucose + isocitrate (2.71 ± 0.33 r.u.), glucose + malate (2.75 ± 0.38 r.u.), glucose + monomethyl-succinate (2.64 ± 0.42 r.u.) or glucose + dimethyl-α-ketoglutarate (2.36 ± 0.33 r.u.) comparing to glucose alone (1.73–2.02 r.u.) or no substrate (1.76 ± 0.33 r.u.). The optimal FCCP concentration was the highest (1.75 μM) upon glucose + glutamine + pyruvate combination and the lowest (0.5 μM) upon glutamate, combinations of glucose with isocitrate, malate, succinate or α-ketoglutarate. Respiration acceleration after FCCP application was the highest with dimethyl-α-ketoglutarate. Following the peak respiration, time-dependent deceleration was observed. It increased with FCCP concentration and depended on oxidative substrate type. Deceleration was the highest upon malate or isocitrate oxidation but was not observed in case of glutamine or dimethyl-α-ketoglutarate oxidation. Pyruvate alone or in combination with glutamine and glucose significantly decreased the depolarizing effect of FCCP on mitochondrial membrane potential and increased respiration elasticity coefficient with respect to the membrane potential change. Thus, in pancreatic acinar cells, the combination of pyruvate, glutamine and glucose enables the optimal adaptive respiratory response to membrane depolarization
How can exact and approximate solutions of Einstein's field equations be compared?
The problem of comparison of the stationary axisymmetric vacuum solutions
obtained within the framework of exact and approximate approaches for the
description of the same general relativistic systems is considered. We suggest
two ways of carrying out such comparison: (i) through the calculation of the
Ernst complex potential associated with the approximate solution whose form on
the symmetry axis is subsequently used for the identification of the exact
solution possessing the same multipole structure, and (ii) the generation of
approximate solutions from exact ones by expanding the latter in series of
powers of a small parameter. The central result of our paper is the derivation
of the correct approximate analogues of the double-Kerr solution possessing the
physically meaningful equilibrium configurations. We also show that the
interpretation of an approximate solution originally attributed to it on the
basis of some general physical suppositions may not coincide with its true
nature established with the aid of a more accurate technique.Comment: 32 pages, 5 figure
Approaches to the Monopole-Dynamic Dipole Vacuum Solution Concerning the Structure of its Ernst's Potential on the Symmetry Axis
The FHP algorithm allows to obtain the relativistic multipole moments of a
vacuum stationary axisymmetric solution in terms of coefficients which appear
in the expansion of its Ernst's potential on the symmetry axis. First of all,
we will use this result in order to determine, at a certain approximation
degree, the Ernst's potential on the symmetry axis of the metric whose only
multipole moments are mass and angular momentum.
By using Sibgatullin's method we analyse a series of exacts solutions with
the afore mentioned multipole characteristic. Besides, we present an
approximate solution whose Ernst's potential is introduced as a power series of
a dimensionless parameter. The calculation of its multipole moments allows us
to understand the existing differences between both approximations to the
proposed pure multipole solution.Comment: 24 pages, plain TeX. To be published in General Relativity and
Gravitatio
Uncoupled respiration stability of isolated pancreatic acini as a novel functional test for cell vitality
Background. Assessment of cell viability is crucial in cell studies. Testing plasma membrane integrity is a traditional approach of evaluating cell viability. Mitochondrial functional capacity closely correlates with plasma membrane integrity and overall cell health. This study aimed to investigate whether any aspect of mitochondrial adaptive capacity in isolated pancreatic acini is associated with the quality of isolated pancreatic acini preparations, as determined by the dye exclusion method.
Materials and Methods. Experiments were carried out on male Wistar rats weighing 250–300 g. A suspension of isolated pancreatic acini was obtained using collagenase. The rate of oxygen consumption of rat isolated pancreatic acini was measured with Clark oxygen electrode. Basal respiration of isolated pancreatic acini was recorded for approximately 2 min. Afterwards, the mitochondrial adaptive capacity was examined using FCCP in concentrations from 0.5 to 2 μM. Uncoupled respiratory stability was calculated as a ratio of respiration rate at high and low FCCP concentrations. Plasma membrane integrity was assessed with trypan blue staining. A total of 74 preparations of isolated pancreatic acini were used in this study.
Results. In all experiments, 92–99 % of pancreatic acinar cells exhibited negative trypan blue staining, indicating intact plasma membranes. The basal and maximal uncoupled respiration rates were not affected by the fraction of trypan-negative cells. However, acini preparations with <less than 95 % plasma membrane integrity had significantly lower uncoupled respiration rates when exposed to a high concentration of FCCP (2 µM), indicating reduced stability of uncoupled respiration.
Conclusions. Results of the study suggest that the stability of uncoupled respiration can serve as a novel metabolic functional test to complement the existing methods for assessing cell vitality
Evolution equation of quantum tomograms for a driven oscillator in the case of the general linear quantization
The symlectic quantum tomography for the general linear quantization is
introduced. Using the approach based upon the Wigner function techniques the
evolution equation of quantum tomograms is derived for a parametric driven
oscillator.Comment: 11 page
Оформлення курсових, дипломних і магістерських робіт
Описані вимоги до оформлення курсових, дипломних і магістерських робітЗміст : ВСТУП 1 ; 1. СТРУКТУРА РОБІТ 6 ; 2. ОФОРМЛЕННЯ РОБІТ 9 ; 2.1. Загальні вимоги до тексту 9 ;
2.2. Титульна сторінка 11 ; 2.3. Рубрикація 12 ; 2.3.1. Класична система рубрикації 12 ; 2.3.2. Рубрикація науково-технічної літератури 14 ; 2.4. Зміст 15 ; 2.5. Посилання на літературу в тексті 15 ;
2.6. Ілюстрації 18 ; 2.7. Таблиці 20 ; 2.8. Формули 21 ; 2.9. Список літератури 22 ; 2.9.1. Елементи бібліографічного запису документа 22 ; 2.9.2. Бібліографічні описи книг 31 ; 2.9.3. Бібліографічний опис частини книги і статті у збірнику або періодичному виданні 31 ; 2.9.4. Бібліографічний опис рукописів і науково-технічних документів 35 ; 2.10. Оформлення додатків 38 ; ДОДАТКИ 39 ; Додаток 1. Зразки оформлення титульних сторінок 39 ; Додаток 2. Зразок оформлення змісту дипломної роботи з використанням рубрикації науково-технічної літератури 43 ; Додаток 3. Зразок оформлення змісту дипломної роботи з використанням класичної рубрикації 44 ; Додаток 4. Зразки оформлення ілюстративного матеріалу 45 ; Додаток 5. Приклади оформлення таблиць 48 ; Додаток 6. Вимоги до оформлення курсових, дипломних і магістерських робіт 49
Charged Dual String Vacua from Interacting Rotating Black Holes Via Discrete and Nonlinear Symmetries
Using the stationary formulation of the toroidally compactified heterotic
string theory in terms of a pair of matrix Ernst potentials we consider the
four-dimensional truncation of this theory with no U(1) vector fields excited.
Imposing one time-like Killing vector permits us to express the stationary
effective action as a model in which gravity is coupled to a matrix Ernst
potential which, under certain parametrization, allows us to interpret the
matter sector of this theory as a double Ernst system. We generate a web of
string vacua which are related to each other via a set of discrete symmetries
of the effective action (some of them involve S-duality transformations and
possess non-perturbative character). Some physical implications of these
discrete symmetries are analyzed and we find that, in some particular cases,
they relate rotating black holes coupled to a dilaton with no Kalb--Ramond
field, static black holes with non-trivial dilaton and antisymmetric tensor
fields, and rotating and static naked singularities. Further, by applying a
nonlinear symmetry, namely, the so-called normalized Harrison transformation,
on the seed field configurations corresponding to these neutral backgrounds, we
recover the U(1)^n Abelian vector sector of the four-dimensional action of the
heterotic string, charging in this way the double Ernst system which
corresponds to each one of the neutral string vacua, i.e., the stationary and
the static black holes and the naked singularities.Comment: 19 pages in latex, added referenc
Motivation of Research and Innovation
One of the key resources of the organization and implementation of professional activity in any field of knowledge and the field of application is the inner motivation of the parties at its constant upgrading and improvement. Development and implementation of a format for life organization and conduct of professional development is fundamentally changing the understanding and attitudes of practicing managers to the place, role, and value of interaction with scientific and educational groups. This is most evident in establishing and maintaining their participation in the joint with the faculty of the University departments of scientific research, conferences and publications on an ongoing basis. First of all, it is typical for graduates of the graduate school, Ph.D. degree and continuing professional self-improvement, as a part of doctoral studies, and through independent programs. This generates obvious advantages of joint development of the sphere of professional management and scientific-educational environment
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