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Currently, practical health care does not have a means to transfer patients health data when they change the place of residence and employment. In this regard, there was a need to develop a health-related instrument to accompany an individual when he/she changes the place of residence and work. The aim of the study was to develop an "individual resistance card" to use in health care for patients with diseases of the genitourinary system.We developed an "individual resistance card" proposed to implement in the practice of health care, as an information document on the state of reactivity and resistance (health) of the organism in terms of urologic diseases.The degree (index) of relative organism resistance is calculated based on impaired individual reactivity and power (intensity) of the environmental pathogenic factors. Its application allows for significant improvement in the effectiveness of periodic health checks, primary and secondary prevention of diseases, because it takes into account both a primary (genotypic) and secondary (acquired) reactivity.The developed Card can be used to record the state of the organism reactivity and resistance regarding urologic diseases and monitor these indicators when the patients change the place of residence and employment. This e-card (in encrypted form) and paper versions may accompany the individuals throughout their lives and will be used for to effectively organize primary and secondary disease prevention by a general practitioner and an urologist.

Low-temperature (20–360°C) exoemission of negative charges from nanocrystalline hydroxyapatite Ca10(PO4)6(OH)2 was studied. Thermal cycling and storage at 20°C were found to induce self-organization processes with charge separation and the formation of a negatively charged layer on the surface. The negative charge formed was long retained at elevated temperatures and only decreased during cooling in the temperature region of the structural transition, as is characteristic of thermoelectrets. No stable electrets formed in hydroxyapatite samples calcined at a high temperature (>800°C).

Positron annihilation lifetime spectroscopy (PALS) was used for calculation of number density and effective sizes of free volume holes (inter-crystallite spaces) in polycrystal CaSO 4 , CaCO 3 (vaterit) and Ca 10 (PO 4 ) 6 (OH) 2 (apatite). The effect of substitution of two-valence Ca(II) for three-valence Eu(III) on annihilation characteristics of apatite, studied together with the data on thermo-stimulated luminescence (TSL) and low-temperature sorption of gas (N 2 ), helped to elucidate mechanism of positronium atom (Ps) localization in the free volume holes and perform corresponding calculations. It came out that PALS is more sensitive to inter-crystallite sites (10 16 cm −3 ) in polycrystallites than to the free volume holes in polymer glasses (10 19 cm −3 ). This is due to higher mobility of the precursor of localized Ps in crystallites.

Based on the analysis of literature data and our own research, we have developed the original concept of etiology and pathogenesis of peptic ulcer disease. An analysis of the literature shows that none of the theories of pathogenesis of peptic ulcer disease does not cover the full diversity of the involved functions and their shifts, which lead to the development of ulcers in the stomach and the duodenum. Our neurogenic-genetic theory of etiology and pathogenesis of gastric ulcer and duodenal ulcer very best explains the cause-and-effect relationships in the patient peptic ulcer, allowing options for predominance in one or the other case factors of neurosis or genetic factors. However, it is clear that the only other: combination of neurogenic factor with genetically modified reactivity of gastroduodenal system (the presence of the target organ) cause the chronicity of the sores. The theory of peptic ulcer disease related to psychosomatic pathologies allows us to develop effective schema therapy, including drugs with psychocorrective action. On the basis of our theory of the role of Helicobacter pylori infection is treated as a pathogenetic factor in the development of peptic ulcer disease.

The study included a total of 109 patients presenting with combined atherosclerotic lesions of coronary and renal arteries. Depending on severity of angina pectoris, the patients were subdivided into two groups. Group One consisted of patients subjected to revascularization of the myocardium and kidneys, and Group Two comprised those with a dominating clinical picture of vasorenal hypertension syndrome and undergoing surgery on renal arteries alone. Combined revascularizations were carried out in 31 patients. Of these, five underwent single-stage endovascular interventions on coronary and renal arteries. Isolated interventions were performed in 78 patients. Selectivity of revascularisations of vascular basins was determined first of all by the degree of coronary impairments, arterial hypertension, and the presence of chronic renal failure. No cases of hospital lethality were registered. The 10-year survival rate after renal revascularization amounted to 80.1%, after combined operations to 90.9%. In the immediate postoperative period improvement following isolated renal revascularization was achieved in 62 (86.1%) patients, after isolated coronary artery bypass grafting and combined operation - in all patients. The long-term outcomes turned out to be better after combined operations (80.0%) as compared to those after isolated operations on renal arteries (70.3%).

This paper considers optically inactive molecules possessing a symmetry plane. Degenerated excited electronic states in such molecules may, in principle, differ in symmetry with respect to mapping onto the symmetry plane. Should this prove the case, the parity-nonconserving electron-nuclear interaction (PNI) causes the degenerated electronic level to suffer a splitting linear in the Weinberg constant. The paper analyzes from this standpoint the lowest-lying excited states in the ten-electron HF, NH3, B2, and H2O molecules. Two of them, namely HF and NH3, possess the necessary and sufficient symmetry properties for such a linear splitting to occur. Factors are discussed that augment the PNI-induced splitting of the excited states under consideration in comparison with the splitting of the ground state in left- and right-handed modifications of optically active molecules. Computations confirm the occurrence of a great (≈10−13 eV) splitting of the levels being considered due to the PNI effect. A similar effect can also occur in the electronic ground state of paramagnetic molecules, such as NO. The computation uses the consistent multiple-electron perturbation theory with a model single-electron central field bare potential. The computer code used is a modification of the original code developed for precision atomic calculations. All the computations boil down to the solution of a single set of ordinary differential equations, i.e., a unidimensional procedure.

This is a theoretical study of argon plasma under conditions, where Ne- and Na-like ionization stages are dominant. Balance equations are generalized to treat 37 3l states of Ne-like ion and 37 adjacent series of Rydberg states of Na-like ion simultaneously. This allows us to include in the kinetics a diffusion-like motion of the state of the system Ne-like ion plus one electron through the multitude of excited levels spread over an energy region of 50 eV. The populations Ni - i (i = (1, ..., 37)) of the Ne-like ion states are introduced explicitly; those of adjacent 37 Rydberg series are accounted for through continuous functions Ni(e). These functions describe the population distribution within each Rydberg series dependent on the Rydberg electron enegy e. The elementary processes of the collisionalradiative model connecting all Ne- and Na-like states, as well as processes of redistribution of populations inside each Rydberg series, are accounted for. The rate coefficients for all processes within the Ne-like residue have been calculated previously, using a detailed many-body relativistic theory. The dielectric capture cross sections and autoionization probabilities are presented as analytical continuation of the collisional excitation cross sections. The excited-excited states transitions are included. The rest of the processes are treated in a simple semiclassical approximation. The Lotz formula is generalized by unambiguous analytical continuation to cover the case of bound-bound transitions between Rydberg states of Na-like ions. The radiation reabsorption in a long plasma cylinder is included through Biberman-Holstein coefficients for all transitions. The inclusion of Na-like states, accounting for diffusion-like processes, increases the population inversion for the lasing candidates by at least a factor of two for a wide range of plasma conditions. This is important for the ionization equilibrium too. Besides, the functions Ni(e) bear diagnostic information. Detailed calculations have been done for the homogeneous steady-state Maxwellian plasma. The role of transient processes in the population inversion creation is under discussion.

It is shown that the calculation of atomic constants by some versions of the multi-configurational method, or its relativistic generalizations, violates the principles of a consistent theory based upon the quantum electrodynamic (QED) approach. The consequences of this violation for the radiative transition probabilities are under investigation. We obtained the probabilities of innershell radiative transitions in Ne-like argon and iron in the lowest approximation of a consistent theory. These results are compared with the corresponding data from some recent publications.

A new calcium copper orthophosphate Ca10Cu(PO4)7 has been prepared and characterized. The compound is stable in the temperature range of 300–1200 K in inert atmosphere or 300–680 K in air. The compound Ca10Cu(PO4)7 is crystallized in the rhombohedral system with whitlockite-type structure. The space group is R3C, the lattice constants are: a=10.442(1), c=37.39(1) A , V=3531(1) A 3 . There are two different copper sites in the structure.

Alpha emitting is treated as a particular case of the nucleus decay. The classical Hamiltonian of the nuclear system is constructed, accounting for the Coulomb inner-nuclear interaction and strong interaction approximated by the "Yukava plus exponent" potential. The effective quantization in terms of the collective variable T (elongation) is performed. The effective mass, adjacent to T, depends on T and is of tensor character; its tensor character, is shown, can manifest itself in the collisional experiment as the "dependence of the potential barrier height" on the incident particle energy. The numerical calculations for 210Po show that the mass tensor character is of principal value for the spectrum of the emitted alpha-particles. The possible consequences for the secondary processes in the atomic electron shell and for the electron-positron pair production are discussed.

Numerical calculations of the inner-shells atomic ionization probabilities and of the electron?positron pair production probabilities (in the bare nucleus) are carried out. The spectra of the ejected electrons as well as the spectra of the produced positrons have fine quasi-periodical structures (~ 3000 eV) scaled by the inverse length of the De-Brogle wave of the ?-particle. Another, large scale type, structurization is governed by the inverse length of the De-Brogle wave of the free electron or positron. The structure of the emitted light particles spectra is shown to be very sensitive to the model of the nucleus decay.

We operated on a total of twenty-seven patients presenting with acute massive thromboembolism of pulmonary arteries. The patients' mean age amounted to 38.6 ± 9.17 years. The estimated pressure in the pulmonary artery averaged 54.2 ± 7.15 mm Hg. A total of twenty- two thromboembolectomic procedures were performed in the setting of assisted circulation. In five patients embolectomy was carried out from a thoracotomic approach without artificial circulation. The remote period was marked by a relapse of thromboembolism, with the female patient having completely refused to undergo treatment. All the patients remain in a satisfactory condition, with the estimated pressure in the pulmonary artery maintaining at an average level of 27.05 ± 3.11 mm Hg.

The energies and the widths of the Stark resonances for the hydrogen atom are calculated using a new approach. It is based on the operator form of the perturbation theory of the Schrodinger equation. The method includes the physically reasonable distorted-waves approximation in the frame of the formally exact quantum-mechanical procedure. The zero-order Hamiltonian possessing only stationary states is determined only by its spectrum without specifying its explicit form. The method of calculation of the perturbation theory matrix elements is described.

Presented herein is a clinical case report concerning a female patient diagnosed with a pseudoaneurysm of the hepatic artery, chronic panel eatitis, and a pancreatic cyst. The woman was subjected to intravascular treatment consisting in reconstruction of the hepatic artery at the site of the origin of the aneurysmal neck with a stent graft.

Presented herein is a clinical case report regarding a patient who was found to have embolism of the right renal artery with accompanying atrial fibrillation. Open surgery is viewed as a method of choice amongst a variety of the available treatment modalities aimed at re-establishing renal blood supply impaired due to embolism of the renal artery trunk. This clinical example demonstrates a possibility of successful renal revascularization undertaken 72 hours after renal artery embolism. The decision to simultaneously perform a combined surgical intervention consisting of embolectomy from the bifurcation of the renal artery, thrombectomy from it branches, and finally followed by radiofrequency ablation of the cava-tricuspidal isthmus, turned out an appropriate therapeutic policy which yielded a patient-friendly immediate outcome as well as favourable remote results persisting over time.

The problem of the construction of the optimal one-electron representation in the theory of the multielectron atom is reduced to the minimization of the gauge dependent multielectron contribution to the radiation widths of atomic levels. The minimization criterion is numerically tested by calculation of the resonance radiation transition probability in the Na-like ion SVI taking into account the core polarization effects.

The values of energies and autoionization widths of 4f13 j6s(J12)ns, np (J) Tm states are presented. These values are calculated by the relativistic perturbation theory with zero-order model approximation. The contribution of effects of the first non-vanishing order (first perturbation theory order for the energies and second order for the autoionization widths) is formally calculated exactly. The effects of higher perturbation theory orders are effectively accounted for. The states superposition is reduced to diagonalization of the secular energy matrix of the states with the same j, n, l and J. Two types of autoionization decay are possible for the states investigated: Beutler-Fano decay and reorientation decay. The reorientation decay has been proved to be the main decay channel when it is due to the monopole interaction of the ejecting Rydberg electron with the atomic residue. Some possibilities of observation of the states studied and measurement of their autoionization widths are proposed.

The numerical calculation of the electron-positron pair production cross-section is carried out. The positron energy spectrum has narrow peaks and dips related to resonance states of the compound superheavy nucleus. The contribution of the spontaneous channel to these irregularities proved to be insignificant in our model. The process takes place mainly at the internuclear separations about 40 fm. The more complicated system with residual atomic shells can be treated in the same way. It is shown that the positron and electron spectra appearing in this system must be modulated by the NS'-resonances.

The electron-positron pair production in collisions between two heavy nuclei with near-threshold energy is considered. A consistent quantum-mechanical approach to the electron-nuclear system as a whole is developed, account being taken of the relativistic nature of the electron subsystem. The motion of the electron and nuclear subsystems is regarded as being independent in the zero-order approximation. The high-order corrections coupling of the two subsystems are accounted for effectively. The model potential of the whole system accounts for the finite size of nuclei and possible resonances of the superheavy compound nucleus formed from the original nuclei. The zero-order potential of the electron subsystem satisfies the following conditions: (1) its spectrum qualitatively coincides with the spectrum of the potential of the electric field of the compound nucleus including the diving of the bound atomic state into the negative continuum at super-critical total nuclear subsystem charge Z, (2) the "no-particle" state of the system is stationary relative to the spontaneous pair production in the zero-order approximation, (3) the perturbation is small at any internuclear separation and vanishes at asymptotically large separations. Resonance phenomena in the nuclear subsystem lead to the structurization of the positron spectrum produced. The fine structurization reflecting details of the compound nucleus spectrum is the characteristic feature of the system with a rather shallow potential pocket (< 1 MeV). The article deals with this effect.

The search for new materials with special optical properties, including luminophores, is basically performed empirically. At the same time on the basis of crystallochemical representations by variation of the anionic and cationic compositions of the phases, purposeful synthesis of compounds with a given structure and physicochemical characteristics can be performed. In this direction a low-temperature modification of calcium orthophosphate [i], which is related to the structural type of the natural mineral whitlockite is of definite interest [2].

Calculation of the electron radial Green's function leads to solution of a system of ordinary differential equations for three functions: F, G, which represent the regular solution of the Dirac equation for r → 0, and W− (the antiWronskian) —a function regular everywhere: W− = 1 for r = 0; W− ≈ 1/r as r →∞. An algorithm is formulated for calculating boundary values of W− as r → 0 and for estimation purposes at asymptotically large values of r.

The creation of electron-positron pairs in the collision of two heavy nuclei is considered. A systematic quantum-mechanical approach is developed for the complete electron-nuclear system. The finite size of the nuclei and the possible resonances of the superheavy compound nucleus formed from the initial nuclei are taken into account. The energetic approach known in the theory of the breakdown of quasisteady systems is generalized to the case of the collisional problem. This approach is combined with perturbation theory for the complete electron-nuclear system. The rearrangement of the negative-continuum spectrum is taken into account using the procedure of [14], which is generalized with the aim of introducing additional conditions, in particular, the condition associated with correct choice of the zero approximation. The method is the same for Z Zcr, where Zcr is the minimum nuclear charge at which spontaneous pair creation is possible. The contribution of the “spontaneous” channel to the amplitude of the process is automatically taken into account.

Biological activity of zeolite-containing tripoli powder was studied in rats. Biochemical, enzymatic and lipid peroxidation indices were assessed. The results of the study confirm enterosorption and detoxication activity of the powder.

An experimental study on 62 guinea pigs was made to examine a magnetic-laser effect on the levels of histamin, serotonin, catecholamine, heparin and pathomorphology of wound healing after operations in the abdominal cavity. Magnetolaser therapy promotes fast normalization of the above levels, suppression of inflammatory-necrotic processes and stimulation of reparative and regenerative processes.

In a dense and cold laser-produced plasma the measured intensity of ${\mathrm{\ensuremath{\alpha}}}_{2}$\ensuremath{\rightarrow}${\mathrm{\ensuremath{\alpha}}}_{1}$ transitions in highly ionized atoms may be strongly influenced by dielectronic satellites ${\mathrm{\ensuremath{\alpha}}}_{2}$nl\ensuremath{\rightarrow}${\mathrm{\ensuremath{\alpha}}}_{1}$nl with a high value of the principal quantum number n of the ``spectator'' electron. This effect may be partially or fully responsible for the reported [Y. Chung, P. Lemaire, and S. Suckewer, Phys. Rev. Lett. 60, 1122 (1988); Y. Chung, H. Hirose, and S. Suckewer, Phys. Rev. A 40, 7142 (1989)] observation that the intensity branching ratio of lines depends on the parameters of the laser-produced plasma.

Evolution of levels populations in Ar plasma with varying parameters is under theoretical investigation. The model imitates fast compression and expansion of the capillary plasma column. The role of the HYDROGEN admixture is discussed.

Energy level populations and spectral line intensities in plasmas are studied using an advanced uniform approach for the calculation of ion energy levels and elementary processes rate coefficients in plasmas. The spectrum of Ne-like argon for the uniform steady-state plasma is calculated for a wide variation of electron temperature and density. Hence the most efficient lasing at 5 3p - 3s transitions with wavelengths 697.6, 860.6, 727.5, 725.7, 670.7 angstroms should be expected at 1019 < ne < 1020 cm-3 and Te approximately 60 eV. It is shown that at electron densities of 1015 < ne < 1021 cm-3 ratios of the strongest 3p - 3s line intensities are sensitive to electron density; their dependence on electron temperature is much less pronounced.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

An energy approach based on consistent QED theory is outlined which presents the energy of any decaying atomic state in complex form with the imaginary part responsible for different types of decays. The aim is to study, in a uniform manner, elementary processes responsible for emission-line formation in plasmas. The energy approach is generalized here for the collisional problem. Numerical results on electron collisional strengths and rate coefficients for Ne-like ions are presented. It is shown that collisional rate coefficients are close to their maxima at an electron temperature∼0.30E threshold for iron and ∼0.15E threshold for argon

The structure of β-Ca3 (PO4)2 is known to be similar to that of whitlockite (R3c, Z =21). The cations are distributed in five different positions, the position Ca(4) being only half occupied. The whitlockite network is stable while the filling of the Ca(4) position changes from 0 to 1. The presence of vacancies allows to provide heterovalent substitutions 3Ca2+ = 2M3+ + and Ca2+ + 0 = 2Me+ with limits of compositions Ca9M (PO4)7 and CaloMe(PO4)7 respectively. The possible cation size can be changed from 0.55 A (Fe3+) to 1.51 A (K+). In order to check these suggestions we have synthesized Ca9M(PO4)7 (M = rare earth element, Y, Bi, Fe, Al, In, Sc) compounds, The double phosphates were studied by luminescence, infrared spectroscopy and X-ray diffraction. All these compounds are isostructural to β-Ca3(PO4)2. The cell parameters gradually decrease for M = La-Ho, Y and remain constant for M = Er-Lu. This divergence can be attributed to the change of the coordination number of the rare earth element. A ...

The rates of autoionisation decay of the 4fj13,6s12/(J12)npj (J) Tm states have been calculated. Two qualitatively different channels of autoionisation decay have been considered: 4f52/136s12/npj to 4f72/136s 12/+ in l (Beutler-Fano decay) and 4fj13, 6s(J12)npj to 4fj13,6s12/(J'12)+ in l (reorientation decay). The first process is accomplished with an energy transfer to the Rydberg electron of delta E approximately 8500 cm-1. This channel is opened at n>or=7. The second low-energy decay ( delta E approximately 250 cm-1) is opened at n>or=25. The reorientation decay proceeds without change of the atomic residue electron configuration. The change of the relative rates of radiation and autoionisation decay along the Rydberg series has been investigated. It has been shown that for the system under consideration the radiation decay is at least one order of magnitude lower than the autoionisation one. In most of the cases considered the reorientation autoionisation is the main decay channel, when it is opened.

For pt.I see ibid., vol.10, p.1001 (1977). A formally exact perturbation expansion with a model zeroth-order approximation has been applied to the semi-relativistic equation for a many-electron system. The energy levels of Mo and Zr ions with two electrons or two vacancies above the 1s22s22p63s23p63d10 core have been calculated. It is shown that the experimental spectra for systems with two quasi-particles above the core may be used to investigate more complex spectra, with three or more quasi-particles.

Asymptotically precise calculations have been carried out with n to infinity , for the Rydberg states 4f136sns of the Tm atom, the 4f146sns, 4f146snp states of the Yb atom and the Lu+ ion, the 4f14ns, 4f14np, 4f14nd states of the Yb+ and Lu2+ ions and the 4f146s2ns, 4f146s2np, 4f146s2nd states of the Lu atom. The Lu atom and Yb+ and Lu2+ ions are considered as a system with one electron above the core of the closed shells 4f146s2 or 4f14. The Yb atom and Lu+ ion are regarded as a system with two electrons above the core. The Tm atom is considered as a system with 4f-1 vacancy and the 6s, ns electrons above the 4f14 core. In calculating energies with one electron above the core the energy is extrapolated as a function of the principal quantum number n by the model potential technique. The potential constructed at this stage is used as a zero-order approximation in calculating states with two and three quasiparticles (vacancies and electrons) above the core. The corrections for the energies of the states of two- and three-quasiparticle systems are calculated with the use of the perturbation theory. The first order has been allowed for completely. In the higher orders effective allowances have been made for the corrections which with n to infinity make contributions of approximately 1/n3. Consideration is given to the non-Coulomb features of Rydberg spectra not vanishing within n to infinity .

A theoretical analysis is made of the method of selective ionization of atoms based on selective resonance excitation by laser radiation to quantum states near the ionization threshold and subsequent autoionization decay of the excited states under the influence of an external electric field. The autoionization of atoms in static and pulsed electric fields is considered. Calculation formulas are obtained for the probability of autoionization of a hydrogenlike atom and corrections are computed for the influence of the electron shells. Numerical estimates are obtained for the autoionization of the n = 7–12 states of the Rb atom in an electric field.

The transition probabilities and radiation widths of the 4f136snRlR(nR=10-50, lR=0; 1) Rydberg states of the Tm atom have been calculated in the electric dipole approximation. Special attention has been paid to the manifestation of non-Coulombic properties of the Rydberg states considered. The calculation has been carried out using relativistic perturbation theory with a model zero-order approximation. The formalism of the energy approach to the atomic processes theory has been used. The contributions of the one- and two-quasiparticle effects to the complex energy matrix have evidently been taken into account. The three-quasiparticle effects have been effectively accounted for.

A model potential relativistic method is used to calculate the energies of the lower levels with configurations 4s4p, 4p2, 4s4d, 4p4d in the Zn I isoelectronic series for nuclear charges Z=36-50. The calculation is made in the first order of perturbation theory with the effective inclusion of higher corrections. The role of various correlation effects is evaluated: core polarisation due to outer electrons, superposition of configurations, mutual screening of the outer electrons. As a zeroth approximation the authors obtain the wavefunctions of the outer electron in the field of the core model potential; the model potential parameter being determined from the empirical energy levels of Cu-like ions. An extrapolation procedure for model potential parameters is used for the calculation of energy levels of Cu-like ions. Energy levels 4lj and 5lj of Cu-like ions for Z=36-60 are given with an accuracy of about 0.1%. The accuracy of the energies of Zn-like ions is within 1%.

A formally exact perturbation theory with a model potential is developed as a zeroth approximation for atomic systems. A potential of zeroth approximation for a complex system with an arbitrary number of electrons in an open shell and an arbitrary number of vacancies in the core is constructed semiempirically using experimental data for the simplest spectra of one-electron states in an open shell. A field form of perturbation theory is used to calculate energy corrections. Diagrams of the first two orders are considered and an effective summation is performed of diagrams describing major interactions in the system. Energies of all positive Fe ions with open shells n=3 and 4 and one vacancy (1s, 2s, 2p or 3p) are calculated.

The first few terms of the perturbation expansions for the function and the energy shift of a degenerate state of an arbitrary quantum mechanical system are obtained using the adiabatic formula. It is shown how the expansion for the secular operator may be obtained from the expansion for the function. The results are used to calculate energies of the ground and some excited states and multiplet splittings of some beryllium-like ions.

The local impurity distribution in fluorite single crystals activated by europium, gadolinium and manganese has been studied with the aid of a scanning electron microscope. It is shown that the impurities in a crystal are distributed nonuniformly to form regions enriched and depleted with impurity. It is proved that the nonuniform distribution of activators due to disintegration processes of solid solutions and to the impurity redistribution occurring in the course of annealing of the crystals. The concentration stability limits of solid solutions in the CaF2-EuF2 and CaF2-MnF2 systems have been calculated.

The kinematics of the material motion in a variable magnetic field in the MHD approximation of a strong field and cold plasma is investigated. The variation of magnetic moments of two dipole systems leads to the development of such phenomena as loop prominences, coronal rain and funnel prominences.

The relativistic perturbation theory is applied to the solution of the many-electron Dirac equation. The theoretical consideration is accomplished for some Mg-like ions: S V, Ca IX, Ti XI and Fe XV; the energies of all the states 1s2 2s2 2p6 3l1j1, 3l2j2 are calculated. The Ne-like spectra are calculated for the ions with Z = 16-26; all the states of configurations 1s2 2s2 2p5 3s, 3p, 3d and 1s2 2s2p6 3s, 3p, 3d are considered. The Dirac equation with the central one-particle model potential Vc(r) is accepted as a zeroth approximation; the model potential imitates the core potential of the closed shells. The empirical information about the energy structures of one electron above the core or one vacancy inside the core is used here to construct the zeroth approximation. The perturbation theory first order correction is calculated exactly, the high order contributions are accounted for effectively. Two main types of high order corrections are investigated: "polarization" interaction of two "above core" particles and effect of the mutual screening of these particles.

The first calculation of the ground state of the two-dimensional excitonic molecule has been performed. The authors have used the transformation of the coordinates of four bodies with equal masses which excludes the motion of the centre of mass, and allows the isolation of one weakly interacting quasiparticle and a core of two strongly interacting quasiparticles in an effective three-body problem. Since the core problem is exactly solved and the form of the variational wavefunction of the system takes into account the essential part of the exchange interactions, satisfactory values are obtained for the binding energy of the two- and three-dimensional biexcitons even when using rather simple trial functions. The binding energy is E2=0.12 au for a two-dimensional biexciton and E3=0.013 au for a three-dimensional biexciton.