Nonlinear interfacial waves in a constant-vorticity planar flow over variable depth

Exact Lagrangian in compact form is derived for planar internal waves in a two-fluid system with a relatively small density jump (the Boussinesq limit taking place in real oceanic conditions), in the presence of a background shear current of constant vorticity, and over arbitrary bottom profile. Long-wave asymptotic approximations of higher orders are derived from the exact Hamiltonian functional in a remarkably simple way, for two different parametrizations of the interface shape.Comment: revtex, 4.5 pages, minor corrections, summary added, accepted to JETP Letter

МОРФОЛОГІЧНА ХАРАКТЕРИСТИКА СУДИН АРТЕРІАЛЬНОГО РУСЛА У ХВОРИХ ІЗ СИНДРОМОМ ДІАБЕТИЧНОЇ СТОПИ

Метою дослідження було встановити особливості морфологічних змін судин артеріального русла нижніх кінцівок у хворих із синдромом діабетичної стопи. В основу роботи покладено вивчення 131 гістологічного препарату, який виготовили з біопсійного матеріалу, отриманого у 30 хворих із синдромом діабетичної стопи під час хірургічного лікування. При виконанні морфологічних досліджень використали загальноприйняті гістологічні методики. З метою дослідження судинного русла препарати забарвлювали за допомогою гематоксиліну та еозину, за Хартом, альциановим синім за методом Стідмена, трихромним за Массоном, суданом III. У мікросудинах та артеріях дрібного і середнього калібру порушення проявлялися переважно десквамативно-деструктивними змінами ендотелію з наступним плазматичним просяканням, склерозом та гіалінозом їхніх стінок, проліферацією клітин м’язового шару, тромбуванням просвіту. В судинах крупного калібру виявлялися атеросклеротичні зміни, особливістю яких був циркулярний або сегментарний медіакальциноз та поширення процесу на артерії середнього і навіть дрібного калібру. Такі грубі морфологічні зміни судин викликали порушення механізмів ендотелійзалежної та ендотелійнезалежної регуляції судинного тонусу.

Prophylaxis of complications after radical operations in patients, suffering a mammary gland cancer

Objective. Elaboration of prophylactic measures for complications after radical operations in patients, suffering mammary gland cancer, and estimation of its efficacy. Materials and methods. Immediate results of surgical treatment were analyzed in 147 patients, suffering mammary gland cancer, and distributed, depending on perioperative treatment methods, into: the1st (comparison group) - 92 women-patients, to whom a standard treatment was applied, the second one (main group) - 55 women-patients, in whom complex of prophylactic measures was applied, including organizational, as well as compressive and medicinal therapy. Results. Application of complex of prophylactic measures was accompanied by reduction of the development rate of postoperative oedema from 50% (comparison group) to 25% (p=0.003), the seroma’s formation - from 29 to 11% (p=0.010), development and severity of postmastectomy syndrome, lymphorrhea - from 29 to 18% (p=0,131) and the wounds complications - from 25 to 7.3% (p=0.007). Conclusion. After radical operations with the lymph node dissection in patients, suffering mammary gland cancer, the early morbidity rate is rather high, and mainly connected with lymphovenous drainage outflow. The complex of measures, aiming at minimization of the patients’ stationary stay, early extraction of draining tubes, early activation of the patients, the improved compressive and medicinal therapy permits to reduce the rate and severity of morbidity and to accelerate the patients’ recovery and reconvalescence

ANALYSIS OF DUAL-FREQUENCY INTERFEROMETRY APPLICABILITY FOR TARGET ELEVATION ANGLE MEASUREMENT USING TWO-COORDINATE RADARS

Subject and Purpose. The study deals with the dual-frequency radio interferometry technique, which is based on the employment of two fairly close frequencies with the aim to remove ambiguity of the radar target elevation estimation using 2D-radar and eliminate 2 pm-uncertainty of the signal phase difference measurement. Analysis of random noise action on the accuracy of the elevation angle estimation by the dual-frequency radio interferometry and assessment of practical applicability of the method make up the purpose of the paper. Methods and Methodology. The noise action on the elevation angle measurement accuracy is examined through a series of analytical calculations with the use of statistical analysis methods. The noise in each receiving channel is modeled in terms of additive, statistically independent stationary Gaussian processes with zero mean values and equal variances. The calculation results are checked via computer simulations with statistics estimations for 106 random noise realizations. Results. A correct condition has been developed for the sector width where the target elevation angle is unambiguously estimated depending on the space separation of the antennas (baselines) and the frequency ratio. Expressions for elevation angle estimation errors have been obtained, showing that the error is mainly contributed by the faults in the determination of the ambiguity interval number. A probability of the correct determination of the ambiguity interval number has been derived depending on the signal- to-noise ratio and the frequency difference, indicating that almost one hundred per cent probability of the correct determination of the ambiguity interval number is only achieved when the signal-to-noise ratio exceeds 30 dB. A comparative analysis has been performed between the methods of dual-frequency interferometry and conventional phase-difference direction finding in the case of close X-band frequencies and the same sectors of survey. Conclusions. The dual-frequency radio interferometry technique with close frequencies has been shown to outperform the standard phase-difference direction-finding method only when the signal-to-noise ratio is sufficiently high (over 30 dB). In principle, the accuracy of the technique seems possible to improve by taking significantly different frequencies selected with regard to the scale negotiation condition. However, it should be mentioned that the implementation of the relevant algorithm in practice is much more complicated than the conventional scheme with a single frequency and several antenna baselines

Superconducting properties of sulfur-doped iron selenide

The recent discovery of high-temperature superconductivity in single-layer iron selenide has generated significant experimental interest for optimizing the superconducting properties of iron-based superconductors through the lattice modification. For simulating the similar effect by changing the chemical composition due to S doping, we investigate the superconducting properties of high-quality single crystals of FeSe$_{1-x}$S$_{x}$ ($x$=0, 0.04, 0.09, and 0.11) using magnetization, resistivity, the London penetration depth, and low temperature specific heat measurements. We show that the introduction of S to FeSe enhances the superconducting transition temperature $T_{c}$, anisotropy, upper critical field $H_{c2}$, and critical current density $J_{c}$. The upper critical field $H_{c2}(T)$ and its anisotropy are strongly temperature dependent, indicating a multiband superconductivity in this system. Through the measurements and analysis of the London penetration depth $\lambda _{ab}(T)$ and specific heat, we show clear evidence for strong coupling two-gap $s$-wave superconductivity. The temperature-dependence of $\lambda _{ab}(T)$ calculated from the lower critical field and electronic specific heat can be well described by using a two-band model with $s$-wave-like gaps. We find that a $d$-wave and single-gap BCS theory under the weak-coupling approach can not describe our experiments. The change of specific heat induced by the magnetic field can be understood only in terms of multiband superconductivity.Comment: 13 pages, 7 figure

Dependence of element composition of bile of freshwater and marine fishes on some abiotic and biotic factors

Introduction: The elemental composition and physical properties of fish bile is a very important marker for ecotoxicological and physiological studies as bile is able to accumulate elements from environmental compartments. In the present study we focused on the effects of long term (seasons and years) and spatial distance (different water bodies) as well as other biotic (feeding habits, fish species, gut morphology) and abiotic (water salinity) factors on element composition of bile of 429 individuals belonging to 22 forms/species of fishes. Methods: Element composition was determined using an inductively coupled plasma optical emission spectrometry. The fishes were analyzed from one marine (the Kandalaksha Gulf of the White Sea), two freshwater oligotrophic (Teletskoye and Baunt lakes), and one freshwater eutrophic water body (Chany Lake). In parallel, we have estimated the volume and density of bile from the same fishes using an automatic pipette and electronic balance. Results and discussion: Based on fish bile density and volume data, we hypothesize that gastric fish species (those fishes that have a stomach) require a low volume of bile, but with higher density if compared to agastric fish species (those lacking a stomach) that mainly possessed large volumes of bile, but with a lower density. We have found that the concentrations of the following Na, K, Ca, Mg, S, P (major elements) and Al, Cu, Fe, Sr, Zn (trace elements) were the highest among the 28 elements studied. There were significant findings to contribute to a better understanding of the physiology of bile. First, we have determined the conditions formed in a water body in a given year (season) are more important for element composition of fish bile rather than other tested factors (feeding habits, gut morphology, etc.). Second, the feeding habits of fishes (carnivorous compared to non-carnivorous) had a significant effect based on differences among several elements. Third, the clear distinction between marine and freshwater fishes was found only for K and Na. Understanding which elements are produced as part of waste elimination and those that are present as a consequence of vital biological functions could improve the ecotoxicological study of bile as a marker of heavy metal contamination.The sample collection, expedition, and chemical analyses (for all fish except pike, perch, roach, and ide) were paid by the Russian Science Foundation (grant number 19-74-10054). The sample chemical analyses for pike and perch was supported by the Russian Foundation for Basic Research (grant number 19-34-60028) whereas for roach and ide was paid by Russian international scientific collaboration program Mega-grant (mega-grant № 075-15-2022-1134).info:eu-repo/semantics/publishedVersio

Analysis of the availability of medicines for the treatment of servicemen with injury and wound of the brain

The most important areas that determine the effectiveness of the medical support system at all stages of providing medical assistance to servicemen is the rational use and availability of medicines and pharmaceutical assistance in general. Under the influence of the situation in eastern Ukraine, the instability of the market economy, the existing budget deficit for the military medical service, the availability of certain groups of drugs is of particular relevance, which fully applies to drugs for the pharmacotherapy of injuries and brain injuries. The purpose of the study is to analyze the availability of medicines for pharmacotherapy of injuries and wounds of the brain. In conducting the study, the following methods of analysis were used: system-review, bibliographic and marketing. Analysis of scientific literature data showed that for pharmacotherapy of craniocerebral wounds and injuries such groups of drugs as psychoanaleptics (N06), blood substitutes and perfusion solutions (B05), peripheral vasodilators (C04), calcium antagonists (C08), analgesics (N02) are used. and psycholeptic drugs (N05), etc., which counted 1 300 trade names of drugs. The analysis of the pharmaceutical market in recent years has allowed us to single out three main factors (index) affecting the growth of expenditures on drug provision for servicemen, the replacement index; inflation index; innovation index Analyzing the availability of drugs by price proposals, it was found that the number of inaccessible drugs decreased within five years by more than 30% and amounts to 7.93% or 103 drugs from the total range of drugs for medical support of servicemen with injury and wound of the brain. That is why it is advisable to conclude that the replacement index has almost no effect on reducing the level of drug costs for servicemen/ In the study of the inflation index, it was found that the pricing of domestic drugs depends on the level of inflation, the cost of foreign-made drugs is in direct proportion to the growth of the dollar. Analysis of the innovation index of the domestic drug market for medical support of servicemen with injury and wound of the brain showed that only 77 original drugs are used for pharmacotherapy, which is 5.92% of the total number of drugs

Drug Agranulocytosis

The paper covers the problem associated with the wide availability and uncontrolled use of over-the-counter medicines, particularly analgesics, antipyretics, and anticatarrhal agents, which lead to the occurrence of adverse drug reactions and poisonings and to considerable economic and human losses. The mechanisms of the pathogenesis of drug agranu-locytosis due to the intake of nonsteroidal analgesics and the diagnosis and treatment of this disease are described in detail. The case presented by the authors clearly demonstrates that the possible development of life-threatening complications due to the use of even submaximal permitted doses of widely spread and available anticatarrhal drugs. Key words: antipyretics, analgesics, nonsteroidal anti-inflammatory drugs, drug agranulocytosis, trepanobiopsy, myelo-gram, intensive care unit

Acoustic Response to the Action of Nanosecond Laser Pulses on an In/CdTe Thin-Film Heterostructure

The photothermoacoustic method has been used for diagnostics of thermobarodynamic processes in the metal In(400 nm)/semiconductor (CdTe) thin-film system under nanosecond laser irradiation (7 ns, λ = 532 nm) in natural conditions (in air) and in a liquid medium (water). From the analysis of the data obtained, the dependence of the pressure induced in the energy-release region on the irradiation energy den-sity has been established and the melting threshold of In film has been determined. Under irradiation of In/CdTe in water, the pressure is higher than in air: 17 times higher at the melting threshold of In film and 30 times higher at twice the temperature. It has been found that the laser pulse treatment of In/CdTe/Au samples in water makes it possible to obtain diode structures with better parameters: smaller leak currents and a steeper current-voltage characteristic under the forward bias of the p-n junction