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With the rapid development of industry, large amount of refractory organic pollutants in domestic and industrial wastewater are discharged into water bodies, posing a serious threat to human health and the environment. Advanced oxidation processes (AOPs) based on persulfates have shown outstanding performance in treating refractory organic wastewater, and the use of single-atom catalysts (SACs) can maximize the utilization of metal atoms and reduce the leaching of metal ions, which has a promising application prospect in the activation of persulfates for the degradation of organic pollutants. The preparation methods of single-atom catalysts were summarized, and the advantages and disadvantages of various methods were discussed. The application of single-atom catalysts with metals such as Fe, Co, Mn and Cu in the activation of persulfates for the degradation of organic pollutants was discussed. The mechanisms of single-atom catalysts in activating persulfates and the degradation mechanisms of the persulfate system catalyzed by single-atom catalysts towards organic pollutants were summarized. Finally, the future development of single-atom catalysts in activating persulfates for the degradation of organic pollutants was discussed.

Wastewater transport in sewer networks contributes to the formation and emission of fetid and toxic sewage gases into the environment, one of which is hydrogen sulfide. The emission of gases can have a significant impact on the environment and health of maintenance workers and city residents. The object of the research is the study of the process of hydrogen sulfide emission in the energy dissipation chamber (EDC). The method of two-stage mathematical modeling in the program of finite element analysis ANSYS CFX is applied for the research. Two models have been created, the first one simulates the internal space of the EDC structure itself, and the second one simulates the EDC manhole and the volume of the surrounding air next to it. Mathematical dependences of hydrogen sulfide concentration change at three sections inside the structure are obtained for incoming wastewater flow velocities V = 1 m/s, 1.5 m/s and 2 m/s. The critical flow velocities at which the maximum single threshold limit value will exceed 1 m/s and the threshold limit value of the working area will exceed 1.52 m/s are determined. The methodology for solving the problem of assessing the impact of the EDC object on the environment is formed. The results of the study can be applied in the design of structures for a preliminary assessment and prediction of the impact of a wastewater facility, as well as the selection of the most favorable hydraulic regime.

Bubbles are extensively explored as gas and energy carriers. However, despite notable progress, the bubble transport mechanisms are still poorly understood. At the present time there is not sufficient understanding of whether the body or surface forces play a major role in bubble transport in liquid interfacial systems. This understanding is important to be able to drive oxygen bubble transport. Here, we show the crucial role of solutocapillary forces in oxygen bubble transport in the core of a diffusion-bubbling membrane with a high density of solid/liquid and gas/liquid interfaces that operates under the oxygen chemical potential gradient. In order to describe the transport of oxygen bubbles in the membrane core, we developed a mathematical model. Both the velocity of bubbles and oxygen flux through this membrane predicted by this model agree with experiments. An in-depth understanding of the bubble transport mechanism presented in this study could eventually lead the way to more efficient bubble membrane gas separation, bubble energy generation, and bubble-assisted therapy in the future.

The 19 F NMR chemical shifts of 13 trifluoromethyl derivatives of alkenes, pyrimidines, and indenes were calculated at the DFT level using the BhandHLYP, BHandH, PBE, PBE0, O3LYP, B3LYP, KT2, and KT3 functionals in combination with the pcS-2 basis set. Best result was documented for the BHandHLYP functional: The mean absolute error (MAE) of 0.66 ppm for the scaled values was achieved for the range of about 20 ppm. Solvent, vibrational, and relativistic corrections were found to be rather small, especially when taken in combination, generally demonstrating a slight decrease in the difference between calculated and experimental fluorine chemical shifts. As a measure of the practical importance of these compounds, one should recall that the growing number of life science products that contain trifluoromethyl groups provides a continuing driving force for the development of an effective methodology that enables both regio- and stereoselective introduction of trifluoromethyl groups into both aliphatic and aromatic systems., (© 2023 John Wiley & Sons Ltd.)

A high-level calculation of 1 H and 13 C NMR chemical shifts of α- and β-d-glucopyranoses is carried out at the DFT level with taking into account their conformational composition to reveal the most effective computational protocols. A number of dedicated DFT functionals in combination with Jensen's pcS-n (n = 0-4) family of basis sets were applied to evaluate the most reliable combination. It was found that BHandHLYP/pcS-2 provided the most accurate and reliable computational protocol. Based on the performed calculations, the established computational protocol is generally recommended for the calculation of 1 H and 13 C NMR chemical shifts of a wide series of carbohydrates., (© 2022 John Wiley & Sons Ltd.)

Creating systems for monitoring technology processes based on concentrated energy flows is an urgent and challenging task for automated production. Similar processes accompany such processing technologies: intensive thermal energy transfer to the substance, heating, development of the melting and evaporation or sublimation, ionization, and expansion of the released substance. It is accompanied by structural and phase rearrangements, local changes in volumes, chemical reactions that cause perturbations of the elastic medium, and the propagation of longitudinal and transverse waves in a wide frequency range. Vibrational energy propagates through the machine's elastic system, making it possible to register vibrations on surfaces remotely. Vibration parameters can be used in monitoring systems to prevent negative phenomena during processing and to be a tool for understanding the processes' kinetics. In some cases, it is the only source of information about the progress in the processing zone.

Hypertension is a key cardiovascular disease risk factor leading to premature mortality worldwide. The purpose of the May Measurement Month (MMM) campaign in Ukraine is to improve awareness of hypertension at the individual and population level. Adults (≥18 years) were screened at sites in Ukraine. Data from the MMM17 (19 sites), MMM18 (1 site), and MMM19 (5 sites) campaigns are included in the present analysis. Ideally, three blood pressure (BP) measurements were taken for each participant, and data on lifestyle factors and comorbidities were collected. Hypertension was defined as systolic BP ≥ 140 mmHg and/or diastolic BP ≥ 90 mm Hg (based on the mean of the second and third readings) or being on antihypertension medication. Multiple imputation was used to estimate participants' mean BP where readings were missing. Linear regression models were used to evaluate associations between BP and participant characteristics. Of all 46 549 screenees, 33 307 (71.6%) had hypertension, and 82.6% of whom were on antihypertensive medication. Of all those on medication, 31.4% were controlled to BP < 140/90 mmHg, and of all 33 307 participants with hypertension, 25.9% had controlled BP. Of all participants, 6.6% took statins and 11.2% took aspirin. The analysis of the MMM 2017, 2018, and 2019 campaigns has shown a high proportion of hypertension, insufficient level of awareness, and critically low level of effective BP control in Ukraine. Further MMM screening is needed to increase awareness of high BP and to help improve diagnosis, management, and treatment of hypertension., Competing Interests: Conflict of interest: None declared., (© The Author(s) 2022. Published by Oxford University Press on behalf of the European Society of Cardiology.)

The substituent α-, β-, and γ-effects of the elements of the second and third periods on 19 F NMR chemical shifts are evaluated including the establishment of stereochemical dependence of γ-effect, the latter particularly important in stereochemical studies of fluorine-containing compounds. Benchmark calculations performed for a series of 32 simple inorganic fluorine-containing molecules demonstrated a markedly good correlation between calculated and experimental fluorine chemical shifts characterized by a mean absolute error of 22.5 ppm in the range of about 900 ppm, which corresponds to a 2.5% error in the percentage terms., (© 2022 John Wiley & Sons Ltd.)

Objective: The aim: To investigate the clinical and pathogenetic peculiarities of formation and course of CCP and the relationship between clinical, hemodynamic and neurohumoral factors of comorbidity development in COPD combined with arterial hypertension (AH)., Patients and Methods: Materials and methods: The object of the study were 484 patients with COPD. Among them, 350 patients with CCP as a result of cardiac insufficiency/severe congestive heart failure (COPD III-IV) out of aggravation, combined with AH II stage (non-symptomatic organ damage) and 1 - 3 grades, including 55 patients (43 men, 12 women) with compensated CCP (average age 43.7 ± 3.4 years), and 295 patients (212 men and 83 women) with decompensated CCP and chronic heart failure (CHF), average age 63.2 ± 8.9 years., Results: Results: It was found that the development and progression of the left and right CHF in patients with CCP combined with AH occurs due to the disorders of the central hemodynamic, progression of pulmonary hypertension, bronchial obstruction syndrome, neurohumoral and systemic immunoinflammatory activation, disorders of endothelial regulation of vascular tension, overproduction of epithelial and mitogenic growth factors, inducers of apoptosis, and is accompanied by increasing levels of natriuretic peptides., Conclusion: Conclusions: The main pathogenetic formation mechanisms of the heart failure on the background of CCP combined with AH are: neurohumoral and systematic immune-inflammatory activation with the development of endothelial dysfunction and (neo)angiogenesis, induction of pathological apoptosis, increase in the intrathoracic pressure, and deposition of blood in the extrathoracic tissues, which result in pulmonary and systemic hypertension, metabolic and hemodynamic remodelling and heart dysfunction.

Oxygen-selective membranes are likely to play a leading part in the future separation processes relevant to energy engineering. A newly developed molten copper and vanadium oxide-based diffusion-bubbling membrane with core-shell structure and fast combined oxygen mass transfer is a promising candidate for efficient oxygen separation. In this work, the oxygen bubble nucleation and transport properties of the diffusion-bubbling membrane were experimentally and theoretically studied. Bubble size distribution and cumulative oxygen flux have been plotted as functions of oxygen partial pressure. The relationship between the bubble density, oxygen partial pressure, and oxygen permeation flux was established. The oxygen flux and bubble density vary in the ranges of 3.2 × 10 -8 -1.4 × 10 -7 mol cm -2 s -1 and 1.3 × 10 13 -5.8 × 10 13 m -3 at Δ P O 2 = 0.1-0.75 atm, respectively. The mechanisms of homogeneous, heterogeneous, pseudo-classical and non-classical nucleation are reviewed within the framework of the Cahn-Hilliard model. It is shown that the homogeneous nucleation mechanism is most likely in the membrane core. The estimated values of the interfacial tension, energy barrier, and rate nucleation are 0.02 J m -2 , 5 kT, and 4 × 10 29 m -3 s -1 , respectively.

Oxygen is the second-largest-volume industrial gas that is mainly produced using cryogenic air separation. However, the state-of-the-art cryogenic technology thermodynamic efficiency has approached a theoretical limit as near as is practicable. Therefore, there is stimulus to develop an alternative technology for efficient oxygen separation from air. Mixed ionic electronic-conducting (MIEC) ceramic membrane-based oxygen separation technology could become this alternative, but commercialization aspects, including cost, have revealed inadequacies in ceramic membrane materials. Currently, diffusion-bubbling molten oxide membrane-based oxygen separation technology is being developed. It is a potentially disruptive technology that would propose an improvement in oxygen purity and a reduction in capital costs. Bubbles play an important role in ensuring the oxygen mass transfer in diffusion-bubbling membranes. However, there is not sufficient understanding of the bubble dynamics. This understanding is important to be able to control transport properties of these membranes and assess their potential for technological application. The aim of this feature article is to highlight the progress made in developing this understanding and specify the directions for future research.

The mechanism of the material destruction under discharge pulses and material removal mechanism based on the thermochemical nature of the electrical erosion during electrical discharge machining of conductive materials were researched. The experiments were conducted for two structural materials used in the aerospace industry, namely austenite anticorrosion X10CrNiTi18-10 (12kH18N10T) steel and 2024 (D16) duralumin, machined by a brass tool of 0.25 mm in diameter in a deionized water medium. The optimized wire electrical discharge machining factors, measured discharge gaps (recommended offset is 170-175 µm and 195-199 µm, respectively), X-ray photoelectron spectroscopy for both types of materials are reported. Elemental analysis showed the presence of metallic Zn, CuO, iron oxides, chromium oxides, and 58.07% carbides (precipitation and normal atmospheric contamination) for steel and the presence of metallic Zn, CuO, ZnO, aluminum oxide, and 40.37% carbides (contamination) for duralumin. For the first time, calculating the thermochemistry parameters for reactions of Zn(OH) 2 , ZnO, and NiO formation was produced. The ability of Ni of chrome-nickel steel to interact with Zn of brass electrode was thermochemically proved. The standard enthalpy of the Ni 5 Zn 21 intermetallic compound formation (erosion dust) Δ H 0 298 is -225.96 kJ/mol; the entropy of the crystalline phase S c int is 424.64 J/(mol·K).

Objective: The aim: Of this study was to improve the efficiency of complex medicamental treatment of generalized periodontitis (GP) in patients with concomitant CAD using of differentiated immunotropic therapy, especially herbal medicine «Immuno-ton»., Patients and Methods: Material and methods: 130 patients with GP were observed (43 without and 81 with chronic CAD - stable angina, functional classes II-III (CCS)) with detection of oral hygiene indices for Green-Vermillion, inflammation of gums PMA, bleeding of gums PBI, depth of periodontal pockets (determined by direct method). The levels of TNF-α and sPECAM-1 in gingival fluid were detected by ELISA method., Results: Results: The following article is dedicated to studying on the effectiveness of the proposed method of GP I and II degree of development treatment in patients with a concomitant coronary artery disease (CAD) using of herbal medicines with immunomodulating effect. The offered methods provide disappearance of clinical signs of inflammation in the periodontal tissues and prevention of inflammation recurrence in the long terms. Also, it was proved that usage of the forward method of the GP immunotropic therapy with including of herbal immunomodulators leads to normalization of dynamics of tumor necrosis factor -alfa (TNF-α) and soluble platelet-endothelial cell adhesion molecule -1 (sPECAM-1) in oral fluid of abovementioned contingent of patients., Conclusion: Conclusions: The progression of generalized periodontitis in patients with stable coronary heart disease is accompanied with manifestation of systemic inflammation, which have been reduced by immunomodulator Immuno-Ton and extratemporal gel with "Enterosgel" and herbal concentrate "Dzherelo".

An analysis was made of the field structures in a coaxial laser with fast saturable absorption. In such an efficiently one-dimensional scheme, the integer topological index (charge) naturally arises: the phase incursion of the field envelope when bypassing the aperture, divided by 2π. The topological charge is the winding number for the phase curve introduced for the electric field envelope with increase of the coordinate for fixed time. In the framework of the generalized Ginzburg-Landau equation, shown are finite numbers of plane-wave modes, stable with respect to weak perturbations, and solitonlike modes with inhomogeneous intensity distributions and different topological charge. It was found that the topological charge could change during transient to steady state. The events of these changes alternate with formation of cusps of the phase curve occurring when extrema of the field intensity and phase coincide.

This publisher's note contains corrections to Opt. Lett.45, 3284 (2020)OPLEDP0146-959210.1364/OL.394727.

Phosphorus-carbon spin-spin coupling constants in a series of salient heterocyclic phosphines were calculated at the SOPPA(MP2) level including evaluation of relativistic and solvent effects. A number of the locally dense basis set schemes were thoroughly investigated in terms of their accuracy versus computational demands. The most effective computational scheme was tested in a benchmark series to provide a very good correlation between 2 J PC calculated at the SOPPA(MP2) level and experiment. A marked dihedral angle dependence of 2 J PC was demonstrated, and this could be used in stereochemical studies of a wide series of organophosphorus compounds based on the phosphorus-carbon coupling constants.

Structuring of matter with nanoobjects allows one to generate soliton-like light bundles with extreme characteristics-temporal duration and spatial dimensions. On the other hand, structuring of light gives the possibility to form light bundles with complicated internal structure; their topology could be used for information coding similar to that in self-replicating RNA molecules carrying genetic code. Here we review the both variants of structuring. In the first variant, we consider a linear molecular chain and organic film interacting resonantly with laser radiation. Demonstrated are optical bistability, switching waves, and dissipative solitons, whose sizes for molecular J-aggregates can reach the nanometer range. We also discuss some theoretical approaches to take into account multi-particle interaction and correlations between molecules. In the second variant, light structuring in large-size laser medium with saturable amplification and absorption is achieved by preparation of the initial field distribution with a number of closed and unclosed vortex lines where the field vanishes. Various types of topological solitons, parameter domains of their stability, and transformation of the solitons with slow variation of the scheme parameters are presented.

For three-dimensional tangle laser solitons that have a number of unclosed and closed vortex lines and coexist in a range of the scheme parameters, we predict irreversible hysteretic transformation of their internal structure when a system parameter slowly and regularly varies crossing the boundary of the stability of one or another soliton. During the hysteresis cycle, when restoring the initial parameter value, the soliton topology simplifies (decrease of topological indices), its field energy decreases, and the energy of the medium increases. The transient includes a series of elementary reactions: reconnection of vortex lines, separation of closed vortex loops after strong bending of a parent vortex line, and twist of unclosed vortex lines changing topological indices. During the transient, new (metastable) types of localized topological structures arise. It is shown that the tangent energy flow along closed vortex lines is unidirectional or direction alternating.

A number of computational schemes for the calculation of 15 N and 31 P NMR chemical shifts and shielding constants in a series of azoles, phospholes, and phosphazoles was examined. A very good correlation between calculated at the CCSD(T) level and experimental 15 N and 31 P NMR chemical shifts was observed. It was found that basically solvent, vibrational, and relativistic corrections are of the same order of magnitude and alternate in sign, being, on average, of about 2-3 ppm in absolute value but, being much larger (up to 14 ppm) in the case of solvent molecules explicitly introduced into computational space. At the DFT level, the performance of nine exchange-correlation functionals including six conventional gradient functionals and three hybrid functionals was studied. The most accurate results were reached with the OLYP and Keal-Tozer's family of functionals, KT1, KT2, and KT3, while the most popular B3LYP and PBE0 functionals showed the most unreliable results. On the basis of these data, we highly recommend OLYP and KT2 functionals for the computation of 15 N and 31 P NMR chemical shifts at the DFT level in the diverse series of nitrogen- and phosphorus-containing heterocycles. Benchmark calculations of 15 N and 31 P NMR chemical shifts in a series of larger nitrogen- and phosphorus-containing heterocycles were performed at the DFT level in comparison with experiment and revealed the OLYP functional in combination with the aug-pcS-3/aug-pcS-2 locally dense basis set scheme as the most effective computational scheme.

This article presents a review of recent investigations of topological three-dimensional (3D) dissipative optical solitons in homogeneous laser media with fast nonlinearity of amplification and absorption. The solitons are found numerically, with their formation, by embedding two-dimensional laser solitons or their complexes in 3D space after their rotation around a vortex straight line with their simultaneous twist. After a transient, the 'hula-hoop' solitons can form with a number of closed and unclosed infinite vortex lines, i.e. the solitons are tangles in topological notation. They are attractors and are characterized by extreme stability. The solitons presented here can be realized in lasers with fast saturable absorption and are promising for information applications. The tangle solitons of the type described present an example of self-organization that can be found not only in optics but also in various distributed dissipative systems of different types.This article is part of the theme issue 'Dissipative structures in matter out of equilibrium: from chemistry, photonics and biology (part 1)'., (© 2018 The Author(s).)

Mixed ionic-electronic conducting (MIEC) membranes attract the attention because of their high potential for oxygen separation and energy conversion applications. The different fabrication methods of asymmetric membranes consisting of a thin MIEC layer on porous support were developed. The basically dense but not completely hermetic thin layers were achieved. To overcome this problem, we suggest a new concept of bilayer MIEC-Redox membrane. This solid/liquid composite membrane consists of a gastight MIEC thin external layer and a thick internal layer in which the redox reactions and oxygen bubbling occur. Here, we report the transport properties of a copper oxide-based MIEC-Redox membrane.

We consider the evolution of the 2-soliton (breather) of the nonlinear Schrödinger equation on a semi-infinite line with the zero boundary condition and a linear potential, which corresponds to the gravity field in the presence of a hard floor. This setting can be implemented in atomic Bose-Einstein condensates, and in a nonlinear planar waveguide in optics. In the absence of the gravity, repulsion of the breather from the floor leads to its splitting into constituent fundamental solitons, if the initial distance from the floor is smaller than a critical value; otherwise, the moving breather persists. In the presence of gravity, the breather always splits into a pair of "co-hopping" fundamental solitons, which may be frequency locked in the form of a quasi-breather, or unlocked, forming an incoherent pseudo-breather. Some essential results are obtained in an analytical form, in addition to the systematic numerical investigation.

We predict a new class of three-dimensional (3D) topological dissipative optical one-component solitons in homogeneous laser media with fast saturable absorption. Their skeletons formed by vortex lines where the field vanishes are tangles, i.e., N&#95;{c} knotted or unknotted, linked or unlinked closed lines and M unclosed lines that thread all the closed lines and end at the infinitely far soliton periphery. They are generated by embedding two-dimensional laser solitons or their complexes in 3D space after their rotation around an unclosed, infinite vortex line with topological charge M&#95;{0} (N&#95;{c}, M, and M&#95;{0} are integers). With such structure propagation, the "hula-hoop" solitons form; their stability is confirmed numerically. For the solitons found, all vortex lines have unit topological charge: the number of closed lines N&#95;{c}=1 and 2 (unknots, trefoils, and Solomon knots links); unclosed vortex lines are unknotted and unlinked, their number M=1, 2, and 3.

A gas-tight and ductile solid/liquid δ-Bi 2 O 3 -0.2 wt% B 2 O 3 electrolyte for molten oxide fuel cells (MOFCs) is developed. The MOFCs are a new class of intermediate temperature fuel cells. The composite, consisting of solid (δ-Bi 2 O 3 ) and liquid (molten Bi 2 O 3 + B 2 O 3 ) oxygen ion-conducting phases, demonstrates the promising application as an MOFC electrolyte with the highest oxygen ionic conductivity.

We predict and study a new type of three-dimensional soliton: asymmetric rotating and precessing stable topological-dissipative-optical localized structures in homogeneous media with saturable amplification and absorption. The crucial factor determining their dynamics is the ratio of the diffusion coefficients characterizing the frequency dispersion and angular selectivity (dichroism) of the scheme. These vortex solitons exist and are stable for overcritical values of the selectivity coefficients and can be realized in lasers of large sizes with saturable absorption.

We present a novel solid/liquid Co3O4-36 wt % Bi2O3 composite that can be used as molten oxide membrane, MOM ( Belousov, V. V. Electrical and Mass Transport Processes in Molten Oxide Membranes. Ionics 22 , 2016 , 451 - 469 ), for ultrahigh purity oxygen separation from air. This membrane material consists of Co3O4 solid grains and intergranular liquid channels (mainly molten Bi2O3). The solid grains conduct electrons, and the intergranular liquid channels predominantly conduct oxygen ions. The liquid channels also provide the membrane material gas tightness and ductility. This last property allows us to deal successfully with the problem of thermal incompatibility. Oxygen and nitrogen permeation fluxes, oxygen ion transport number, and conductivity of the composite were measured by the gas flow, volumetric measurements of the faradaic efficiency, and four-probe dc techniques, accordingly. The membrane material showed the highest oxygen selectivity jO2/jN2 > 10(5) and sufficient oxygen permeability 2.5 × 10(-8) mol cm(-1) s(-1) at 850 °C. In the range of membrane thicknesses 1.5-3.3 mm, the oxygen permeation rate was controlled by chemical diffusion. The ease of the MOM fabrication, combined with superior oxygen selectivity and competitive oxygen permeability, shows the promise of the membrane material for ultrahigh purity oxygen separation from air.

Relativistic calculations of (29)Si NMR shielding constants (chemical shifts) in the series of halosilanes SiX(n)H(4-n) (X = F, Cl, Br and I) are performed within a full four-component relativistic Dirac's scheme using relativistic Dyall's basis sets. Three different theoretical levels are tested in the computation of (29)Si NMR chemical shifts in comparison with experiment: namely, four-component relativistic GIAO-DFT, four-component relativistic GIAO-RPA, and a hybrid scheme of a nonrelativistic GIAO-MP2 with taking into account relativistic corrections using the four-component relativistic GIAO-RPA. The DFT results give larger relativistic effects as compared to the RPA data which might be rationalized in terms of the manifestation of correlation effects taken into account at the DFT level and not accounted for at the uncorrelated RPA level. Taking into account solvent effects slightly improves agreement with experiment, however, being not a matter of principle. Generally, relativistic pure nonempirical wave function methods perform much better as compared to relativistic DFT methods when benchmarked to experiment.

The main factors affecting the accuracy and computational cost of the calculation of (31)P NMR chemical shifts in the representative series of organophosphorous compounds are examined at the density functional theory (DFT) and second-order Møller-Plesset perturbation theory (MP2) levels. At the DFT level, the best functionals for the calculation of (31)P NMR chemical shifts are those of Keal and Tozer, KT2 and KT3. Both at the DFT and MP2 levels, the most reliable basis sets are those of Jensen, pcS-2 or larger, and those of Pople, 6-311G(d,p) or larger. The reliable basis sets of Dunning's family are those of at least penta-zeta quality that precludes their practical consideration. An encouraging finding is that basically, the locally dense basis set approach resulting in a dramatic decrease in computational cost is justified in the calculation of (31)P NMR chemical shifts within the 1-2-ppm error. Relativistic corrections to (31)P NMR absolute shielding constants are of major importance reaching about 20-30 ppm (ca 7%) improving (not worsening!) the agreement of calculation with experiment. Further better agreement with the experiment by 1-2 ppm can be obtained by taking into account solvent effects within the integral equation formalism polarizable continuum model solvation scheme. We recommend the GIAO-DFT-KT2/pcS-3//pcS-2 scheme with relativistic corrections and solvent effects taken into account as the most versatile computational scheme for the calculation of (31)P NMR chemical shifts characterized by a mean absolute error of ca 9 ppm in the range of 550 ppm., (Copyright © 2014 John Wiley & Sons, Ltd.)

A combined theoretical and experimental study of the stereochemical behavior of (31)P-(1)H spin-spin coupling constants has been performed in the series of trivinylphosphine and related trivinylphosphine oxide, sulfide and selenide. Theoretical energy-based conformational analysis of the title compounds performed at the MP2/6-311G** level reveals that each of the four compounds of this series exists in the equilibrium mixture of five true-minimum conformers, namely s-cis-s-cis-s-cis, s-cis-s-cis-gauche, syn-s-cis-gauche-gauche, anti-s-cis-gauche-gauche and gauche-gauche-gauche, which were taken into account in the conformational averaging of (31)P-(1)H spin-spin couplings calculated at the second-order polarization propagator approach/aug-cc-pVTZ-J level of theory. All (31)P-(1)H spin-spin coupling constants involving phosphorus and either of the vinyl protons are found to demonstrate a marked stereochemical dependences with respect to the geometry of the coupling pathway and internal rotation of the vinyl group around the P-C bond which is of major importance in the stereochemical studies of the unsaturated phosphines and phosphine chalcogenides., (Copyright © 2010 John Wiley & Sons, Ltd.)

The paper contains results of surgical treatment of 52 patients with extramedullary spinal tumors. Resection of tumors was performed using hemilaminectomy and microsurgical technique. In all cases tumors were resected totally. Follow-up data are also presented (periods of follow-up ran to 6-10 years). Control examination was complemented by MRI and X-ray spondilograms. No signs of instability and other complications were found. With reference to our own experience and literature data we discuss the possibilities of radical resection of extramedullary tumors via hemilaminectomy. This allows to avoid postoperative vertebral instability. At the same time we emphasize that despite minimally traumatic approach and high effectiveness in removal of lateral and dorsolateral tumors, hemilaminectomy in certain degree limits possibilities of radical resection of tumors located someway ventrally.

The paper considers postoperative imbalance of the trace elements zinc and copper in 40 surgical patients aged 47.2 +/- 17.1 years who have extensive purulent soft tissue wounds (PSTW). In 90% of the patients with PSTW, plasma Zn++ levels were much lower than the reference values (the normal value was 11.1-19.5 micromol/l) while in 47.5%, serum Zn++ was in the range of less than 7 micromol/l, which is a poor prognostic factor. There was a negative correlation between the level of Zn++ and that of C-reactive protein (CRP) and a positive correlation between the former and the magnitude of a reduction in transferrin (TF) as a marker of protein-energy malnutrition. Plasma Cu/Zn ratio is shown to be of very clinical importance. The higher this ratio (normal ratio 0.9-1.13) is, the more severe the general condition of patients with PSTW, the higher CRP values (above 120 mg/l; normal value 0-6 mg/l), and the lower TF levels are. In patients with PSTW, zinc level and Cu/Zn ratio may act as an independent predictor of a grave condition during a systemic inflammatory reaction.

The authors have for the first time evaluated efficacy of embolization of the uterine arteries in uterine myomas depending on peculiarities of the blood flow in the system of the uterine arteries in the context of the B. B. Mandelbrot fractal proportionality.

Theoretical energy-based conformational analysis of bis(2-phenethyl)vinylphosphine and related phosphine oxide, sulfide and selenide synthesized from available secondary phosphine chalcogenides and vinyl sulfoxides is performed at the MP2/6-311G** level to study stereochemical behavior of their (31)P-(1)H spin-spin coupling constants measured experimentally and calculated at different levels of theory. All four title compounds are shown to exist in the equilibrium mixture of two conformers: major planar s-cis and minor orthogonal ones, while (31)P-(1) H spin-spin coupling constants under study are found to demonstrate marked stereochemical dependences with respect to the geometry of the coupling pathways, and to the internal rotation of the vinyl group around the P(X)-C bonds (X = LP, O, S and Se), opening a new guide in the conformational studies of unsaturated phosphines and phosphine chalcogenides., (Copyright (c) 2009 John Wiley & Sons, Ltd.)

The paper presents the results of postoperative studies in 82 patients with major soft tissue phlegmons of the extremities and torso. The basic aspect of the studies concerned the correction of protein-calorie deficiency on the basis of additional nutrition through sipping of hypercaloric formula "Nutridrink" and the standard enteral formula "Nutrisone dry powder", which were given to in 29 and 20 patients, respectively, on postoperative day 1 for 3 weeks. A control group comprised 33 patients who received only diet 1. The findings have indicated that sipping of the enteral formula substantially reduces the catabolic pattern in the patients and facilitates a rapider recovery of the visceral protein pool.

The epidemic foci formed by patients with tuberculosis in the Admiralteisky District, Saint Petersburg in 1994-2005 were surveyed. The study showed that the bulk of the foci had been formed by patients suffering from the clinical forms of tuberculosis without the chronic pattern of a process, that of first-grade epidemic burden. These are most commonly the foci of new-onset tuberculosis; the proportion of comers from other areas and confinement institutions was not greater than 15%. The one-year foci formed by the patients living in the communal flats made up their bulk. Under the conditions of a megapolis, the cases of small epidemic are extremely few and they do not affect the intensity of the bacillary nucleus in the population of the district. The contribution of the foci formed by the homeless and migrants to the formation of the bacillary nucleus was small, but showed a stable upward trend. Every five focus was that of drug-resistant tuberculosis and they were shown to tend to increase.

The present paper comparatively analyzes anesthetic support in 91 patients during a total endoprosthetic operation on the knee joint. All the patients were conventionally divided into 4 groups: (1) those (n=7) in whom the operation had been made under general anesthesia (nitrous oxide, ketamine, seduxen, droperidol, and fentanyl); (2) those (n=36) who had been operated on under epidural anesthesia; (3) those (n=24) who had intraoperatively received spinal (subarachnoidal) anesthesia; (4) those (n=24) whom had been intraoperatively given combined spinal and epidural anesthesia. The study established that the above-mentioned general anesthesia failed to produce a steady-state hemodynamics; the earliest postoperative period being accompanied by a significant pain syndrome, which required the use of narcotic analgesics. In Group 2, due to the specific features of the impact of epidural anesthesia itself on different innervation links (A, B, and C), susceptibility to hypotension and the adequacy of this mode of anesthesia were observed, which required the intraoperative additional administration of narcotic agents to enhance anesthesia. Group 3 was marked by a relative postoperative stability of parameters, but a significant pain syndrome is observed in the earliest postoperative period. The best results were obtained in Group 4 patients undeigone a combined spinal and epidural anesthesia. The component of subarachnoidal (spinal) anesthesia Marcaine Spinal provided a sufficient intraoperative analgesic effect and the component of epidural anesthesia induced virtually no pain syndrome under continuous epidural block.

We reveal the existence of stable dissipative soliton complexes with curvilinear motion of their center of mass. This type of motion results from the field distribution asymmetry and is well pronounced for asymmetric complexes of laser solitons with strong coupling. We present results of numerical simulations of such complexes in a model of wide-aperture lasers or laser amplifiers with saturable gain and absorption. The complex consists of a pair of strongly coupled vortex solitons weakly coupled with a number of other vortex solitons. Similar complexes are expected to exist in different spatially distributed nonlinear dissipative systems, including schemes with discrete dissipative solitons.

We derive governing equations that determine a full polarization state of transversely two-dimensional spatial solitons in a bulk anisotropic medium with the second-order nonlinearity. Based on nonlinear vectorial Maxwell's equations and approximation of slowly varying envelopes, our approach describes also lowest-order nonparaxial effects, however the most important factor governing radiation polarization is the medium anisotropy. This factor results in mixing of orthogonal components of electric field of quadratic soliton that consists of coupled beams at the fundamental frequency and its second harmonics. For the case of weak anisotropy we determine the soliton polarization state by a perturbation method; it turns out that it is elliptical and changing over the soliton transverse section. The approach allows generalization to the case of optical parametric oscillators.

We study, analytically and numerically, the effect of frequency detunings and relaxation processes in laser media on stability and bifurcations of dissipative optical localized structures (DOLS's) in a transversely one-dimensional laser with a saturable absorber. The approximate envelope equation, with an intensity dependent effective coefficient of the diffusion, is derived. Andronov-Hopf bifurcations resulting from frequency detuning and leading to oscillatory DOLS's are analyzed numerically. A numerical and analytical study of bifurcations of transversely motionless DOLS's in a laser with finite relaxation rates of amplifying and absorbing media is performed. New types of DOLS's are found, including those moving with a large transverse velocity and those moving with a periodically oscillating transverse velocity. Hysteresis between different types of DOLS's is demonstrated.

The mucosal biopsies morphological investigation of the lower third of esophagus were conducted for Helicobacter pylori detection in 43 patients with reflux-esophagitis. Helicobacter pylori were detected in 66.7%, gastric metaplasia-in 83.3% of patients. Helicobacter pylori plays an important role in reflux-esophagitis pathogenesis. Surgical treatment is indicated if the combined antireflux and antibacterial therapy is ineffective.

The authors have revised traditional principles of treatment of children with a congenital pathology of the locomotor system. Early treatment has been shown to be necessary beginning from infancy since the operations have a more favourable course. Normal anatomo-physiological correlations of the locomotor system are being formed from the early days and months of the infants. Good immediate results were obtained in 22 children. The authors recommend to establish terms of the operative interventions for orthopedic abnormalities immediately after birth in the maternity home.