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The poor water resistance property of a commercial Mn4+-activated narrow-band red-emitting fluoride phosphor restricts its promising applications in high-performance white LEDs and wide-gamut displays. Herein, we develop a structural rigidity-enhancing strategy using a novel KHF2:Mn4+ precursor as a Mn source to construct a proton-containing water-resistant phosphor K2(H)TiF6:Mn4+ (KHTFM). The parasitic [HMnF6]- complexes in the interstitial site from the fall off the KHF2:Mn4+ are also transferred to the K2TiF6 host by ion exchange to form KHTFM with rigid bonding networks, improving the water resistance and thermostability of the sample. The KHTFM sample retains at least 92% of the original emission value after 180 min of water immersion, while the non-water-resistant K2TiF6:Mn4+(KTFM) phosphor maintains only 23%. Therefore, these findings not only illustrate the effect of protons on fluoride but also provide a novel insight into commercial water-resistant fluoride phosphors.

Light is a fuel for photosynthesis and plays an irreplaceable role in seed germination, stem elongation, leaf expansion, flowering induction, and accumulation of nutrients. However, the current phosphors combined with LEDs for photosynthesis have some unsolved problems, such as low efficiency, poor thermal stability, unvarying emission wavelength or non-matching spectrum, which restrict their applications. In this work, a series of novel efficient Lu3Al5O12:10%Ca2+,xBi3+,yMn4+ phosphors with blue-violet plus deep red dual-emission peaking at 419 and 669 nm have been first reported, which can meet the different light requirements of plants by controlling the concentration ratio of Bi3+ and Mn4+, and they possess at most 90.64% spectrum resemblance to the absorption spectrum of chlorophyll A and B. Furthermore, these phosphors exhibit high internal efficiency and at most reserve 95% of the initial intensity at 425 K. Finally, as a light source for monitoring the fluorescence spectra of evergreen plants, pc-LEDs were fabricated by UV chips and our synthesized phosphors. The results reveal that these phosphors can achieve as high as 83% photosynthetic efficiency for evergreen plants and improve it by 10% than a single emission phosphor, which shows good application prospects for improving plant photosynthesis.

The conclusion of the Expert Council reports an agreement on the place of the P2Y 12 receptor blocker prasugrel in the early invasive treatment of patients with acute coronary syndrome ACS, according to the results of the multicenter randomized controlled study ISAR-REACT 5. Prasugrel should be considered the preferred P2Y 12 receptor blocker in the planned primary percutaneous coronary intervention and early invasive management of patients with ST segment elevation ACS. Herewith, prasugrel intake in patients with non-ST segment elevation ACS is preferable after coronary angiography and decision for coronary stenting.

Scientific-methodical approaches to a study of nonlinear physicochemical processes are considered and an experimental setup intended for investigation of nonlinear physical and chemical processes accompanying irradiation of solids of various classes (including energetic materials) by UV, visible, and IR laser radiation is described. The possibility of synchronous multi-parameter measurements of the amplitude, spectral, kinetic, and spatial characteristics of the near-surface and bulk luminous laser plasma, solid-phase luminescence, acoustic pulses formed in the bulk of the samples, and morphology of residual damages has been demonstrated with a nanosecond time resolution. The energy density on the irradiated target surfaces varied from fractions of mJ/cm2 to 104 J/cm2 depending on the problem to be solved. The spectral range recorded for one irradiation pulse was 200–1100 nm, the spectral resolution was ~1.5 nm, and the spatial resolution was ~10 μm. A pressure pulse formed in the sample volume was recorded by an acoustic sensor with sensitivity of 0.15 V/bar and temporal resolution of ~5 ns.

The paper studies the threshold, spectral, and kinetic characteristics of the luminescence of compacted samples from inert and energetic materials induced by their irradiation with the first harmonic of a neodymium laser (1064 nm, $\tau=16$ ns). The results establish that irradiation of pure (without specially introduced impurities) samples with laser radiation with an energy density of (0.5–3) J/cm2 forms so-called hot spots on their surface, the characteristics of which are determined by absorbing inhomogeneities (already present or introduced during sample preparation) and parameters of laser radiation. The atomic lines of alkali metals–Na and K–are predominant in the emission spectra. Multi-pulse excitation leads to annealing of absorbing inhomogeneities and increased optical breakdown threshold. In the samples with specially introduced aluminum impurities (composites), the luminescence and destruction thresholds are an order of magnitude smaller; the spatial distribution over the irradiated surface is close to homogeneous, and there are Al atomic lines in the luminescence spectra. The results obtained are interpreted via the concept of low-threshold optical breakdown, which develops on absorbing optical inhomogeneities and leads to the formation of near-surface laser plasma.

The autographic method was used to study the morphology of the damage occurring on the surface of metals and in polymethylmethacrylate (PMMA) after a single exposure to an electron beam formed in the vacuum diode of a pulsed electron accelerator in the modes of filamentation and self-focusing. It was found that in the zones of interaction between the filamentous beam and PMMA at a depth of $40-80\ \mu\mathrm{m}$ , micro-fractures of a round and more complex shape with a diameter of $10-50\ \mu\mathrm{m}$ form. The mechanism of local microdestruction formation is analyzed.

Patient flow often described as a systemic issue requiring a systemic approach because hospital is a collection of highly dynamic, interconnected, complex, ad hoc and multi-disciplinary sub-processes. However, studies on holistic patient flow simulation following system approach are limited and/or poorly understood. Several researchers have been investigating single departments such as ambulatory care unit, Intensive Care Unit (ICU), emergency department, surgery department or patients’ interaction with limited resources such as doctor, endoscopy or bed, independently. Hence, this article demonstrates how to achieve system approach in constructing holistic patient flow simulation, while maintaining the balance between the complexity and the simplicity of the model. To this end, system approach, network analysis and discrete event simulation (DES) were employed. The most important departments in the diagnosis and treatment process are identified by analyzing network of hospital departments. Holistic patient flow simulation is constructed using DES following system approach. Case studies are conducted and the results illustrate that healthcare systems must be modeled and investigated as a complex and interconnected system so that the real impact of changes on the entire system or parts of the system could be observed at strategic as well as operational levels.

The physical nature of emissions excited in pressed-sugar samples by the first harmonic of a neodymium laser (1064 nm, 12 ns) is studied. The spectral, kinetic, spatial, and amplitude characteristics of emissions upon single- and multipulse irradiation with energy densities of 0.012–3.2 J/cm2 are measured. It is found that excitation of a sample by the first pulse causes two emission types, namely, emission of the second harmonic of a Nd laser (532 nm) and glowing of dense low-temperature plasma formed as a result of a low-temperature optical breakdown on absorbing inhomogeneities. Multipulse excitation leads to annealing of absorbing inhomogeneities and to an increase in the optical breakdown threshold.

The development of ablative pulsed plasma thrusters (APPT) continues at RIAME MAI. In 2014 one of them, APPT-45-2, was mounted on board the small spacecraft MKA-FKI PN2 developed by the S.A. Lavochkin Scientific and Production Association. Now in cooperation with the Scientific Technical Innovation Center “TECHCOM” the electric propulsion system (EPS) APPT-250 of the next generation is being developed, that is intended for the orbit maintanance of the constellation of small communication satellites. Power consumption of EPS is from 60 to 120 W, the total thrust impulse is 15.6 kN•s. APPT-250 differs from the earlier APPT-based propulsion systems by substantially lower mass. A digital power processing unit (PPU), developed by “TECHCOM”, and power capacitors with high specific energy intensity are used for the first time.

The paper provides data on the structures and specifications of laser printers for 3D metal printing. The printers were engineered in Research and Educational Center "Modern manufacturing technologies" in Tomsk Polytechnic University, Tomsk, Russia. The essential difference of the given printers is their laser power. The experimental research has shown that the setups with a more powerful laser (500W) enable synthesizing the objects of higher quality in a shorter period of time. The paper also presents data on forming samples structure with the use of 3D printing.

The given paper presents the flowchart of the worked out SLS print setup. The setup consists of a laser source, a reactor tube, a laser sweeping system (scanatory system), a control unit, a gas supply and pumping-out system, a melting process visual review system. The paper covers the results of the given setup operation, introduces a sample made with the use of SLS printing and some of its parameters.

The article reports the results of the experiment studied the effect of radiation spectral content (considering its equal intensity in terms of photosynthetically active radiation) on the growth and development of Boets greenhouse tomato breed. We have shown that the effective development of model subjects requires the adaptation of radiation spectral content depending on the growth period and type of a plant, unlike the illumination level. The obtained results demonstrate the necessity of creating an adaptive irradiation unit.

Nowadays, Mn4+-doped oxide phosphors have attracted more and more attentions owing to their widespread applications in white LEDs, optical data storage and agricultural production, but these phosphors have two most significant problems including thermal quenching (TQ) and low quantum efficiency. Here, we report a far-red-emitting LaAlO3:3%Ca2+,1%Bi3+,0.1%Mn4+ perovskite phosphor which exhibits zero-TQ even up to 150 °C and high internal quantum efficiency (IQE) of 89.3%. To our best knowledge, the zero-TQ phenomenon is first realized in Mn4+-activated perovskite phosphors caused by the synergistic action of Ca2+ and Bi3+ which is attributed to the efficient energy transfer, energy compensation and structural rigidity enhancement. Moreover, the gratifying luminous performance improvement is obtained due to charge compensation effect, optimized crystal field and excited electrons transfer. The main emission peak of this phosphor is monitored at ~730 nm which perfectly matches the absorption spectrum of phytochrome PFR which has a good application prospect for improving plant seed germination, flowering, fruiting and aging. These findings may provide a feasible way to simultaneously improve thermal stability and quantum efficiency of Mn4+ luminescence in oxide hosts.

An automated system for integrated electrophysical and optical studies of semiconductor nanoheterostructures, which operates in a wide temperature range from 15 to 475 K, is designed. The setup is intended to measure the temperature and frequency admittance and electroluminescence spectra of light-emitting diode and laser chips formed on substrates of diameter up to 50.2 mm, and the distribution of parameters over the wafer. The setup includes the closed-cycle helium cryogenic station, LCR meter, and temperature controller. The characterization results of nanoheterostructures with InGaN/GaN multiple quantum wells, which are used for creating highly efficient white and blue light-emitting diodes, are presented.

Light plays a vital role on the growth and development of plant. On the base of white light with high color rendering to the benefit of human survival and life, we proposed to improve “color rendering” of LED lighting for accelerating the growth of lettuce. Seven spectral LED lights were adopted to irradiate the lettuces under 150 μmol·m−2·s−1 for a 16 hd−1 photoperiod. The leaf area and number profiles, plant biomass, and photosynthetic rate under the as-prepared LED light treatments were investigated. We let the absorption spectrum of fresh leaf be the emission spectrum of ideal light and then evaluate the “color rendering” of as-prepared LED lights by the Pearson product-moment correlation coefficient and CIE chromaticity coordinates. Under the irradiation of red-yellow-blue light with high correlation coefficient of 0.587, the dry weights and leaf growth rate are 2–3 times as high as the sharp red-blue light. The optimized LED light for lettuce growth can be presumed to be limited to the angle (about 75°) between the vectors passed through the ideal light in the CIE chromaticity coordinates. These findings open up a new idea to assess and find the optimized LED light for plant growth.

In solving various kinds of problems detect and determine elevation of coordinates of air targets requires modelling of the underlying surface for breeding secondarily emitted from the target of the probing signal. For this, you need to deduce the dependence, bind the elevation of the target with a radar portrait derived from the underlying surface.

Today, there are a wide variety of algorithms for suppression of impulse noise. One such algorithm is median Altering. One of the main goals of this work is to analyze the qualitative characteristics of the median filter, as one of ways of compensation of impulse noise. The achievement of this goal will contribute to the modelling of the median filters in environments of computer-aided design MatLab and MaxPlus.

The complexity of problems of the theoreticaldescription of the crystallization process was noted bymany experts. For example, E.N. Kablov stated thefollowing in [1, p. 300] when considering the directedcrystallization process of heatresistant nickel alloys:“Description of the morphology of the phase boundary when taking into account the instabilities that ariseis very difficult even for singlephase alloys.”N.P. Lyakishev and G.S. Burkhanov [2, p. 140] adhereto the same opinion: “Until now there has been nosufficiently complete theory of crystallization ofeutectic alloys explaining the formation of variouseutectic structures.” According to [2], the first attemptat explaining the formation mechanism of lamellareutectics was undertaken by Tamman, while Fogelassumed that both phases grow simultaneously, and, inthis case, their common interfaces should be perpendicular to the interface between solid and liquidphases. Vast experimental material on the problem offormation of various structures upon crystallizationfrom solutions and melts including the description ofthe wellknown Lisegang structures and attempts atconstructing a theory of similar phenomena considered in monograph [3] of F.M. Shemyakin andP.F. Mikhalev had been accumulated already by 1938.According to [3], it was G.V. Woolf who in 1926 proposed for the first time to consider the formation of analloy crystal structure of eutectic composition as anunstable process accompanied by the alternate formation of crystallites of one component or another.Thus, this problem has been formulated over a longtime, and all available means have been used for itssolution. It is of interest to note that, for describing thealternation of rings formed during the crystallizationof a deposit from solution (Lisegang structures), Susann Weil (1931) proposed to use the formulas following from quantum mechanics, where the ring numberis an analogue of the quantum number. In this case,good agreement between the calculated and experimental results [3] was obtained.Nowadays, it is possible to consider as an established fact that the complex structures arising duringcrystallization, for example, alloys, are a consequenceof the development of certain instabilities during thephase transition. However, there are many causes forthe occurrence of instabilities and, as experimentalinvestigations show, various variants of their development can be implemented. Without claiming completeness, it is possible to list the following possibilitiesleaving the priority for the development of the phasetransition instability:(i) concentration overcooling;(ii) convective flows deforming the temperaturefield (gravitational and thermocapillary convection);(iii) phase stratification.In addition, the elastic properties of the solid phase[2] (one example is epitaxial crystallization on substrates [4, 5]) as well as the thin structure of the phaseboundary (atomically smooth or diffuse surfaces [1,p. 298]) and the adsorption phenomena [6] also give acertain contribution. The adsorption phenomenadetermine the surface energy (surface tension), wetting, and spreading and, thus, can cause thermocapillary convection [7–9]. Nevertheless, nowadays there isno general approach to description of the causes of theoccurrence of all variants of structures arising duringthe solidphase formation from melt or solution,which are a consequence of the instability of the processes accompanying the phase transition. Materialscience achieved a significant success, especially anapplied one, but the further development of this fieldof science determining the technical progress in many

On the basis of the designed complex of low-temperature admittance spectroscopy, the electron spectrum of semiconductor light emitting diode (LED) heterostructures with InGaN/GaN multiple quantum wells was investigated. The features of the construction of the measuring complex, as well as the technique of measurements of semiconductor nanoheterostructures and processing of admittance spectra, are presented.

A mathematical model is proposed to describe the process of crystallization. This model reflects experimentally established properties of structure formation in instability zones. Contemporary approaches to the theoretical description of crystallization yield values of the solid phase growth rate that differ, by several orders, from those observed in experiments. This fact stimulated the construction of a mathematical object that reproduces the basic instabilities of the process and stabilizes their feedback. The creation of this object required matching between the micro and the macro scales, as well as between wave and diffusion processes. The paper also gives a physical interpretation and results of the numerical analysis of the said model.

BACKGROUND Nanomaterials offer greatly improved ionic transport and electronic conductivity compared with conventional battery and supercapacitor materials. They also enable the occupation of all intercalation sites available in the particle volume, leading to high specific capacities and fast ion diffusion. These features make nanomaterial-based electrodes able to tolerate high currents, offering a promising solution for high-energy and high-power energy storage. However, there are still many challenges associated with their use in energy storage technology and, with the exception of multiwall carbon-nanotube additives and carbon coatings on silicon particles in lithium-ion battery electrodes, the use of nanomaterials in commercial devices is very limited. After decades of development, a library of nanomaterials with versatile chemical compositions and shapes exists, ranging from oxides, chalcogenides, and carbides to carbon and elements forming alloys with lithium. This library includes various particle morphologies, such as zero-dimensional (0D) nanoparticles and quantum dots; 1D nanowires, nanotubes, and nanobelts; 2D nanoflakes and nanosheets; and 3D porous nanonetworks. Combined with lithium and beyond lithium ions, these chemically diverse nanoscale building blocks are available for creating energy storage solutions such as wearable and structural energy storage technology, which are not achievable with conventional materials. ADVANCES The success of nanomaterials in energy storage applications has manifold aspects. Nanostructuring is becoming key in controlling the electrochemical performance and exploiting various charge storage mechanisms, such as surface-based ion adsorption, pseudocapacitance, and diffusion-limited intercalation processes. The development of new high-performance materials, such as redox-active transition-metal carbides (MXenes) with conductivity exceeding that of carbons and other conventional electrode materials by at least an order of magnitude, open the door to the design of current collector–free and high-power next-generation energy storage devices. The combination of nanomaterials in hybrid architectures, such as carbon-silicon and carbon-sulfur, together with the development of versatile methods of nanostructuring, overcome challenges related to large volume change typical for alloying and conversion materials. These examples indicate that nanostructured materials and nanoarchitectured electrodes can provide solutions for designing and realizing high-energy, high-power, and long-lasting energy storage devices. OUTLOOK The limitations of nanomaterials in energy storage devices are related to their high surface area—which causes parasitic reactions with the electrolyte, especially during the first cycle, known as the first cycle irreversibility—as well as their agglomeration. Therefore, future strategies aim to develop smart assembly of nanomaterials into architectures with controlled geometry. Moreover, combining nanomaterials with complementary functionalities, such as high electronic conductivity of graphene or MXenes with high operating voltage and high redox activity of oxides, is necessary. Building sophisticated electrode architectures requires innovative manufacturing approaches, such as printing, knitting, spray deposition, and so on. Already-developed techniques such as 3D printing, roll-to-roll manufacturing, self-assembly from solutions, atomic layer deposition, and other advanced techniques should be used to manufacture devices from nanomaterials that cannot be made by conventional slurry-based methods. Such manufacturing approaches can also enable long-sought flexible, stretchable, wearable, and structural energy storage and harvesting solutions for Internet of Things and other disruptive technologies.

The energy thresholds and ignition delays of pressed samples of a stoichiometric pyrotechnical mixture of ammonium perchlorate and ultrafine aluminum are studied as functions of the diameter of the laser spot created by a millisecond laser pulse. A clearly expressed size effect is found. A characteristic size determining the boundary between the wide and narrow beams of the laser pulse applied is determined. The influence of optical properties of the examined composition on the behavior of the size dependences is discussed. The relation between the nature of the size effect and the laws of light scattering in the volume of powdered pyrotechnical mixtures is considered.

The polymerase chain reaction with arbitrary primers (RAPD–PCR) was used to study and to evaluate the genetic variation in the hybrid progeny of two Cyprinidae species, common bream Abramis brama L. and roach Rutilus rutilusL. Genetic polymorphism was studied in 20 fishes (young of the current year) obtained in four individual crosses: R. rutilus × R. rutilus (RR), A. brama × A. brama (AA), R. rutilus × A. brama (RA), and A. brama × R. rutilus (AR). Amplification spectra obtained with eight primers contained 288 fragments, 97.6% of which proved to be polymorphic. The proportion of polymorphic fragments was 75.0% in the RR progeny, 58.1% in the AA progeny, 84.9% in the AR progeny, and 77.8% in the RA progeny. Classification analysis in the space of principal components was performed with the first four components, which together accounted for 64% of the total variance of the character under study. The individual contributions of components I, II, III, and IV were 26.8, 16.8, 11.5, and 8.9%, respectively. Fishes of the two pure species and the hybrid progeny (direct and reverse hybrids together) were clearly differentiated in the space of principal components I and II. The best differentiation of the four samples (RR, AA, RA, and AR) was observed in the space of principal components II and IV. Possible causes of high genetic variation in interspecific hybrids are discussed.

In this paper, a graphene decorated SiC nanomaterial (graphene@SiC) fabricated via a facile adiabatic process was physicochemically characterised, then applied as a supercapacitor material and as an anode within a Li-ion battery (LIB). The reported graphene@SiC nanomaterial demonstrated excellent supercapacitative behaviour with a relatively high power density and specific capacitance of 4800 W·kg−1 and 394 F·g−1, respectively. In terms of its capabilities as an anode within an LIB, the layered-graphene overwhelms the Li-intercalation, which is reflected in the obtained specific capacity of 150 mAh·g−1, with a columbic efficiency of ~99% (after 450 cycles) at a current of 100 mA·g−1.

We report on the existence of a newly recognized extensive solid-solution series between taimyrite and tatyanaite, its Pt-dominant analogue. Copper probably occupies a separate site. Substitution involving Pd and Cu also is important, such that taimyrite–tatyanaite forms a solid-solution series with cabriite, which is structurally closely related to taimyrite and tatyanaite. These platinum-group minerals ( PGM ) occur in base-metal sulfide ( BMS ) ores in the Oktyabr’sky deposit, Noril’sk complex, Siberia, Russia. The taimyrite–tatyanaite is present as single grains and aggregates, associated with a heterogeneous Ag–Au alloy, and also as zoned intergrowths of Pt–Pd–Cu stannides. These intergrowths commonly, but not necessarily, occur within chalcopyrite and typically display the following sequence of crystallization, based on textural and compositional data: atokite–rustenburgite → tatyanaite → Pt-rich taimyrite → taimyrite poorer in Pt → late-stage Ag–Au alloys. Subsolidus re-equilibration of the atokite–rustenburgite core with the Cu-rich host is considered unlikely to produce the peripheral zones of the Cu-rich PGM around this core. These zoned PGM probably formed from a trapped liquid rich in noble metals, Cu, and Sn. Decrease in temperature and increase in activity of Cu in the remaining liquid seem to have been the main factors to control the order of crystallization of the PGM in the zoned intergrowths.

The authors comment on studies of concentration dependencies of luminescence in oscillating systems. Redox system involving ruthenium complexes, uranyl species, and cerium complexes.

Objective: to study the specific features of the mechanisms responsible for the development of acute respiratory distress syndrome (ARDS) induced by direct and indirect damaging factors and to reveal its differential diagnostic signs. Materials and methods. Lung morphological changes were studied creating experimental models of ARDS of various genesis in 75 outbred male albino rats weighing 300—400 g, which included the direct damaging factor acidine-pepsin aspiration (Group 1, n=25) and the indirect damaging factor blood loss (Group 2, n=50). Prospective examinations were made in 73 patients (43 men and 30 women, whose age was 21 to 69 years) with ARDS caused by direct damaging factors, such as aspiration pneumonitis, pneumonia, blunt chest injury, and pulmonary contusion (37 patients, including 21 men and 16 women) and in those with ARDS caused by indirect damaging factors, such as abdominal sepsis, severe concomitant injury, and hemorrhagic shock (36 patients, including 22 men and 14 women). Results. The study has shown that ARDS caused by direct and indirect damaging factors is characterized by different developmental mechanisms and lung morphological changes that underlie the specific features of functional impairments. Conclusion. The findings made it possible to substantiate and propose new approaches to the differential diagnosis and treatment of ARDS caused by direct and indirect damaging factors. Key words: acute respiratory distress syndrome, direct and indirect damaging factors, thoracic and pulmonary compliance, lung extravascular fluid, positive end-expiratory pressure, respiratory support, intensive care unit.

After light irradiation of oil films on water surface the autoxidation process has been found to be of nonsteady auto-oscillatory character, which can be observed in rate oscillations of O2 absorption. Also recorded have been intensity oscillations of the EPR signal from the “radical counter” added into an oil sample. Complex dynamics of autoxidation can be due to an autocatalytic process involving the participation of peroxides accumulated in oil during photooxidation.

The effect of the Ru(bipy)3Cl2 [RuII] complex on chemiluminescence in the autooxidation of diphenylmethane in the presence of BuIOK was studied. The luminescence increases due to the participation of an activator in the redox processes. The excitation of the RII complex occurs in the stage of oxidation by the superoxide anion of the RuI complex formed by the one-electron reduction of the initial RuII by anions.

In this paper the initiation thresholds were measured and kinetics of decomposition was studied for pressed powders of FTDO (furasan-1,2,3,4-tetrazin-1,3-dioxide) at pulsed laser action by different laser wavelengths: 266 nm (zone-to-zone absorption), 532 nm (transparency range), 1.064 nm (transparency range) and 10600 nm (phonon absorption) that corresponds to absorption region (266 nm), transparency range (532 nm; 1064 nm) and phonon absorption (10600 nm) of these explosives.

The paper generalizes the 15 years’ experience of the V. A. Negovsky Research Institute of General Reanimatology, Russian Academy of Medical Sciences, in conducting fundamental studies of the morphological, functional, and clinical patterns of the development of acute respiratory distress syndrome (ARDS), by using up-to-date medical technologies. The developed and clinically introduced new scientifically grounded methods for the prevention, diagnosis, and combination, differentiated treatment of ARDS could reduce the number of complications, the duration of mechanical ventilation, the length of stay in the intensive care unit, and mortality rates. Key words: acute respiratory distress syndrome, V. A. Negovsky Research Institute of General Reanimatology, Russian Academy of Medical Sciences.

By analyzing the data available in the Russian and foreign literature and their many years’ experience, the authors review the state-of-the-art of the problem associated with ventilator-associated pneumonia in intensive care units. The etiology, epidemiology, and pathogenesis of ventilator-associated pneumonia, the possibilities and limitations of its prevention and diagnostic methods, successes and difficulties and treatment of this pathology are described in detail.

Objective: to analyze the causes of fatal outcomes in victims with severe concomitant injury (SCI) in an intensive care unit (ICU) of a multidisciplinary hospital. Subjects and methods. The data on 78 victims with SCI (65 men, 13 women) with SCI without the leading severe brain or spinal injury were retrospectivly analyzed. Results. Intrahospital mortality was 17.9%. The dead and surviving victims had an APACHE II score of 18.4±9.8 and 9.2±7.9, respectively (p=0.0008). According to the ISS scale, injury severity was 41±11.8 scores in the dead and 34.8±10.7 scores in the survivors (p=0.07). The APACHE II and ISS scores were of little prognostic use — AUC (the area under the ROC curve) was 0.19 and 0.35, respectively. Gender and the estimated blood loss volume had no statistically significant impact on mortality. In the structure of mortality, 21.4 and 78.6% fell on early (in the first 5 days after injury) and late (on day 12 or later post-injury), respectively. Late mortality was associated with septic complications in 90.9%. To predict the risk of septic complications, we developed a model including the APACHE II condition severity on admission, chest, limb, and pelvis injury severities. The sensitivity and specificity of the obtained criterion were 87.5 and 84.5%, respectively (AUC 0.88). Conclusion. In SCI, mortality at a present-day multidisciplinary hospital remains high, largely due to late mortality associated with pyoseptic complications. Our developed model may be used in the assessment of fatal septic complications for differentiated prophylaxis.

Objective: to study the informative value of the oxygenation index as a criterion for the diagnosis of acute respiratory distress syndrome (ARDS) of varying genesis. Subjects and methods. Seventy-two patients, including 27 women and 45 men, aged 19 to 65 years admitted to an intensive care unit for various diseases, in whom ARDS was diagnosed on the basis of the traditional criteria, were prospectively examined. The authors analyzed the causes of acute respiratory failure, the time course of changes in gas exchange and PaO2/FiO2, X-ray picture, and the time of respiratory support when respiratory and nonrespiratory treatments were performed. Results. After correction of the extrapulmonary causes of impaired gas exchange, optimization of respiratory support parameters, and use of aggressive artificial ventilation methods and nonrespiratory treatments, 45 (62.5%) of the 72 examinees diagnosed as having ARDS showed a considerable gas exchange improvement and a steady increase in the oxygenation index more than 300; thus, these patients stopped meeting the criteria of ARDS. Conclusion. The oxygenation index is a rather vulnerable sign of ARDS, the time course of changes in which depends on many pulmonary and extrapulmonary causes, which necessitates a comprehensive evaluation of the degree of lung injury, the causes and severity of respiratory failure and, evidently, the refinement and expansion of the criteria for establishing this diagnosis. Key words: acute lung injury, acute respiratory distress syndrome, acute respiratory failure, oxygenation index.

A new method has been found for the identification of copper(III) in high-temperature superconductors, based on recording the light emitted on interaction of the superconductors with tris(2,2′-bipyridyl)ruthenium(II) chloride in solution.

The probability of recoilless absorption for Pd0.95Sn0.05 was found to be nearly independent of pressure. This result has been interpreted using the neutron determined phonon density of states and the Mannheim impurity model (1972). The Pd-Sn force constant is found to be greater than the Pd-Pd nearest-neighbour force constant. The pressure dependence of the electron density at 119Sn is the same when the Sn is in Pd0.95Sn or Pd(12% wt Sn), consistent with the simple rigid-band model. Both the recoilless fraction and the electron density at 119Sn nuclei changed more with pressure in Pd3Sn than in Pd0.95Sn0.05.

1. The effect of oxygen on the chemiluminescent reaction of alkyl organoaluminum compounds with xenon difluoride was determined. The emission becomes stronger or weaker depending on the concentration of oxygen in the solution. 2. In addition to the main source of emission (reactions not containing O2 radicals), there is an additional source due to the transformation of the alkyl radicals (reaction intermediates) into peroxyl radicals, which disproportionate with the emission of light.

Experimental results of the hydrostatic pressure influence on Mossbauer spectrum parameters are obtained over the pressure range including the area of structural phase transition. A linear increase of the Mossbauer effect probability (recoilless fraction) is accompanied by a linear decrease of the electron density at tin nuclei within the pressure range foregoing the phase transition. The electric resistance and the recoilless fraction of the new phase of Mg2Sn are lower, but the electron density at tin nuclei is greater than the initial phase ones. Hydrostatic conditions allow to fix clearly the diphasic transition area and to determine the influence of the pressure on the Mossbauer line position and on the recoilless fraction of the high pressure phase. The phase transition heat Q = 415 cal mol−1 is calculated using recoilless fractions of the high and low pressure phases at 25 kbar. The present results are qualitatively and quantitatively different from the results, obtained at nonhydrostatic conditions. [Russian Text Ignored].

1. Aluminum-free products are formed in the reaction of aluminum alkyl compounds with XeF2 due to the reaction of alkyl radicals with the solvent. 2. A free-radical mechanism for the reaction of the organoaluminum alkyl compounds with XeF2 was established relative to the inhibition of chemiluminescence and gas liberation process. 3. Chemiluminescence was detected upon the reaction of the galvinoxyl inhibitor with XeF2 accompanied by the liberation of gaseous xenon.

1. Chemiluminescence (CL) was observed in the reaction of the unstable organoaluminum peroxide (EtO)2A100Et with H2O. 2. The absence of CL in the reactions of (EtO)EtAl(OOEt) and Et2AlOOEt is related to the rapid decomposition of the starting (Et)3Al and Et2AlOEt in the reaction with H2O. 3. It was shown that the chemiluminescent determination of (EtO)2AlOOEt can be made when its amount in solution ranges from 10−1 to 1.2·10−5 mole/liter.

1. The possibility of detecting organometallic peroxides without decreasing the temperature and hydrolysis of the reaction solution during oxidation of organometallic compounds with oxygen based on the kinetic maxima of the intensity of chemiluminescence was demonstrated. 2. The formation of organometallic peroxides was detected during oxidation of organic derivatives of uranium and lanthanides with oxygen. 3. The stage of formation of an organometallic peroxide during oxidation of organometallic compounds with oxygen takes place more rapidly than the reactions of its subsequent consumption.

Chemiluminescence was found in the reaction of XeF/sub 2/ with (C/sub 2/H/sub 5/)/sub 3/A1 (TEA), (i-C/sub 4/H/sub 9/)/sub 3/ X A1, (i-C/sub 4/H/sub 9/)/sub 2/A1H, and (C/sub 2/H/sub 5/)A1C1/sub 2/ in CH/sub 2/C1/sub 2/. The product composition indicates a redox reaction of XeF/sub 2/ with the A1-C bond. The kinetic curves for the chemiluminescence intensity which feature brightness maxima indicate luminescence excitation in reactions of unstable intermediates. Organoxenon compounds have been proposed for these intermediates.