Anxiety, stress and coping strategies in ukrainian medical students after the year of the russian-ukrainian war

In order to study the influence of coping mechanisms on the level of anxiety and stress in students of higher medicaleducation under martial law, 314 students of the Dnipro State Medical University were interviewed. The median level of anxietywas found to be 7 (4;11) points, with a noticeable difference between men and women. The median level of stress severity was 5(4;7) points, with a significant difference between men and women. Adaptive cognitive strategies were the most prevalent (45.5 %)in the sample, while adaptive, relatively adaptive, and non-adaptive strategies were found in comparable frequency (27.1 % and27.4 %, respectively). It has been determined that implementing adaptive emotional strategies decreases the likelihood ofexperiencing significant levels of anxiety while employing maladaptive emotional strategies increases the risk by 2.79 times. Theutilization of other coping mechanisms does not appear to have a significant impact on the chances of developing severe anxiety

Relativistic instant-form approach to the structure of two-body composite systems

A new approach to the electroweak properties of two-particle composite systems is developed. The approach is based on the use of the instant form of relativistic Hamiltonian dynamics. The main novel feature of this approach is the new method of construction of the matrix element of the electroweak current operator. The electroweak current matrix element satisfies the relativistic covariance conditions and in the case of the electromagnetic current also the conservation law automatically. The properties of the system as well as the approximations are formulated in terms of form factors. The approach makes it possible to formulate relativistic impulse approximation in such a way that the Lorentz-covariance of the current is ensured. In the electromagnetic case the current conservation law is ensured, too. The results of the calculations are unambiguous: they do not depend on the choice of the coordinate frame and on the choice of "good" components of the current as it takes place in the standard form of light--front dynamics. Our approach gives good results for the pion electromagnetic form factor in the whole range of momentum transfers available for experiments at present time, as well as for lepton decay constant of pion.Comment: 26 pages, Revtex, 5 figure

Field on Poincare group and quantum description of orientable objects

We propose an approach to the quantum-mechanical description of relativistic orientable objects. It generalizes Wigner's ideas concerning the treatment of nonrelativistic orientable objects (in particular, a nonrelativistic rotator) with the help of two reference frames (space-fixed and body-fixed). A technical realization of this generalization (for instance, in 3+1 dimensions) amounts to introducing wave functions that depend on elements of the Poincare group $G$. A complete set of transformations that test the symmetries of an orientable object and of the embedding space belongs to the group $\Pi =G\times G$. All such transformations can be studied by considering a generalized regular representation of $G$ in the space of scalar functions on the group, $f(x,z)$, that depend on the Minkowski space points $x\in G/Spin(3,1)$ as well as on the orientation variables given by the elements $z$ of a matrix $Z\in Spin(3,1)$. In particular, the field $f(x,z)$ is a generating function of usual spin-tensor multicomponent fields. In the theory under consideration, there are four different types of spinors, and an orientable object is characterized by ten quantum numbers. We study the corresponding relativistic wave equations and their symmetry properties.Comment: 46 page

Tandem proton accelerator as injector for TRAPP

To inject protons to the TRAPP (synchrotron for therapy of cancer) a tandem accelerator has been constructed. Its parameters are: protons energy is 1.4 MeV, current is 3 mA, pulse duration is 2 μs, frequency is up to 1 Hz. Negative hydrogen ions are extracted through the slit from a magnetron discharge on the heated surface of the LaB6 cathode. The beam of negative ions with an initial energy of 25 kV accelerates up to the half energy in the first accelerating tube, than recharges into protons in gas nitrogen target in a tube at a potential of 700 kV. After that, the proton beam doubles its energy in the second accelerating tube. Operating and control of the tandem are by means of computer

Effect of dynamic blocking of dislocations by interstitial atoms on mechanical properties of metals and alloys

According to the experimentally approved theoretical calculations it has been estab -lished, that under some temperature speed conditions of tension of transition metals and their alloys, a dynamic interaction of the interstitial atoms with dislocations takes place. This effect leads to strengthening of this materils. The temperature of dynamic interaction for hydrogen, oxygen, carbon in iron of two modifications and metals of V-A group are calculated.Согласно теоретическим расчётам, подтвержденным экспериментально, показано, что при определенных температурно-скоростных условиях растяжения переходных металлов и сплавов на их основе происходит динамическое взаимодейстие атомов внедрения с дислокациями, которое приводит к их упрочнению. Рассчитаны температуры динамического взаимодействия для водорода, азота, кислорода и углерода в железе двух модификаций и металлах V-A группы.Згідно теоретичних розрахунків, підтверджених експериментально, показано, що за певних температурно-швидкісних умов розтягування перехідних металів і сплавів на їх основі відбувається динамічна взаємодія атомів упровадження з дислокаціями, яке призводить до їх зміцнення. Розраховано температури динамічної взаємодії для водню, азоту, кисню, і вуглецю в залізі двох модифікацій і металах V-A групи

Phenomenological description of phase transitions in thin BaTiO3 films

Phase transitions in thin epitaxial films of BaTiO3 are described phenomenologically in terms of Landau potentials with sixth-and eighth-order terms. It is established that the phase diagram depends on the electrostrictive constant Q 12. The phase diagrams calculated for different values of Q 12 available in the literature differ qualitatively. The dependence of the misfit strain of a film on the film tetragonality at room temperature is found, which makes it possible to determine the thermodynamic path in the phase diagram for a specific film. The dependences of the spontaneous polarization and dielectric constant of a film on the misfit strain at room temperature are constructed. © 2008 Pleiades Publishing, Ltd

Application of PIXE and PIGE methods for examination of tungsten and rhenium alloys obtained by CVD

The use of nuclear phisics methods of ion beam analysis with registration of K-series X-ray and γ-ray from nuclear reactions for determination of tungsten, rhenium and fluorine in binary alloys obtained by chemical vapor deposition has been presented