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In crop production, the harvesting and use of cuttings of various fruit crops implies their saturation with various media to stimulate cuttings before germination or to increase moisture to the desired level. In this work, a vacuum-infiltration method is proposed for active saturation of plant objects of tubular capillary structure with various media. The advantage of this method is justified over the traditional method of passive soaking. As objects of research were used one-, two- and three-node cuttings with open cuts of apple-tree variety Bely Naliv, apricot variety Melitopolsky and grape variety Shevchenko. It is defined that vacuum-infiltration at a vacuum level of 550 mm Hg does not have a damaging effect on the cuttings, as evidenced by the viability and the time of development of the buds on the cuttings during their cultivation in phytotron conditions. The effectiveness of the active saturation method is shown in a comparative visual assessment of the intensity of staining of the cuttings after vacuum-infiltration and the soaking method. It is determined that the time of saturation of single-nodal cuttings of grapes with an aqueous solution of eosin by the method of vacuum-infiltration is up to 12 sec, while by the soaking method it takes up to 6 hours. It is illustrated the possibility of effective saturation of grape cuttings with solutions of sucrose and glycerin with concentration up to 50%. It is shown that the time of active saturation of cuttings with various solutions depends on their species structure and the number of buds. The proposed method of vacuum infiltration reduces the time of saturation of the plant’s captive parts with stimulating media, more than 10 times. It permits to restore the initial moisture of the cuttings after storage without the stage of soaking. The effective saturation of one-, two- and three-node grape cuttings with media of different viscosity by vacuum infiltration does not exceed 6 minutes, what allows the use of this method in cryobiology.

This paper analyses the behavioral features of ohmic contacts under the conditions of traditional isothermal annealing. The purpose of this paper is to study the value change of the semiconductor contact resistance when applying electric current pulses of different powers. For the experiments, structures were formed of metal-sublayer-semiconductor wafer Al–(Ti, Ni, Mo)–Si. The quality control of the deposited films was carried out microscopically by the four-probe method. The presented results indicate the solid-phase interaction of components during diffusion annealing Si–Me–Al thin-film systems. This rearrangement of atoms, which occurs with grain-boundary diffusion, significantly affects the electrical and thermal characteristics of the formed contacts. The novelty of the paper is that the optimal parameters of a rectangular current pulse were selected, which made it possible to reduce the value of the transition resistance by 1.6 times. [ABSTRACT FROM AUTHOR]

Вызовы, вставшие перед страной в связи с переходом экономики страны на инновационный путь, выводят на новый уровень градоформирующую роль научно-инновационного комплекса страны. Системы расселения регионов РФ вкупе с террито­риальной структурой экономики формировались пре­имущественно на индустриальном этапе развития страны в тесном взаимодействии с производством. При переходе к рыночным принципам организации хозяйства структура экономики регионов, в значительной мере разрушенная в 90-е годы прошлого века, претерпела существенные измене­ния, что обусловило высокую степень пространственной не­однородности экономического роста в регионах, изменение демографической ситуации в муниципальных образованиях, стало причиной деградации части внутрирегиональных систем расселения. Инновационный путь развития меняет роль различных типов поселений в экономике, предъяв­ляя новые требования и к качеству жизни на территории, и к качеству трудовых ресурсов на местном рынке труда. Трансформация экономики, ориентированной на модерниза­цию и инновационный путь развития, должна осуществлять­ся с учётом обеспечения условий для диффузии инноваций на пространственном уровне. Вопросы интенсификации инновационной деятельности приобретают важное значение для повышения качества устойчивого развития как в целом Свердловской области, так и её промышленно-производ­ственного каркаса. Основным драйвером преобразований является научно-инновационный комплекс региона, а местом активизации - территории его преимущественного размещения и развития[1]. [1] Настоящая статья написана на основе раздела «Научно-инновационный комплекс Свердловской области» НИР «Внесение изменений в схему террито­риального планирования Свердловской области» (ОАО «ГИПРОГОР», Москва, 2020 год. Заказчик: Министерство строительства и развития инфраструктуры Свердловской области, госконтракт № ОКЭФ-2019-07 от 28.10.2019).

The effect of extremely low frequency electric and magnetic fields (ELF-EMF) on plants and animals including humans is quite a contentious issue. Little is known about ELF-EMF effect on hydrobionts, too. We studied the effect of square voltage waves of various amplitude, duration, and duty cycle, passed through seawater, on Trichoplax organisms as a possible test laboratory model. Three Placozoa strains, such as Trichoplax adhaerens (H1), Trichoplax sp. (H2), and Hoilungia hongkongensis (H13), were used in experiments. They were picked at the stationary growth phase. Arduino Uno electronics platform was used to generate a sequence of rectangular pulses of given duration and duty cycle with a frequency up to 2 kHz. Average voltage up to 500 mV was regulated by voltage divider circuit. Amlodipine, an inhibitor of calcium channel activity, was used to check the specificity of electrical pulse effect on voltage-gated calcium channels in Trichoplax. Experimental animals were investigated under a stereo microscope and stimulated by current-carrying electrodes placed close to a Trichoplax body. Variations in behavior and morphological characteristics of Trichoplax plate were studied. Stimulating and suppressing effects were identified. Experimental observations were recorded using photo and video techniques. Motion trajectories of individual animals were tracked. Increasing voltage pulses with fixed frequency of 20 Hz caused H2 haplotype individuals to leave “electrode zone” within several minutes at a voltage of 25 mV. They lost mobility in proportion to voltage rise and were paralyzed at a voltage of 500 mV. Therefore, a voltage of 50 mV was used in further experiments. An animal had more chance to move in various directions in experiments with two electrodes located on one side instead of both sides of Trichoplax. Direction of motion was used as a characteristic feature. Trichoplax were observed to migrate to areas with low density of electric field lines, which are far from electrodes or behind them. Animals from old culture were less sensitive to electrical stimulus. H2 strain was more reactive than H1 strain and especially than H13 strain; it demonstrated stronger physiological responses at frequencies of 2 Hz and 2 kHz with a voltage of 50 mV. Motion patterns and animal morphology depended on the duration of rectangular stimulation pulses, their number, amplitude, and frequency. Effects observed varied over a wide range: from direct or stochastic migration of animals to the anode or the cathode or away from it to their immobility, an increase of optical density around and in the middle of Trichoplax plate, and finally to Trichoplax folding and detach from the substrate. Additional experiments on Trichoplax sp. H2 with pulse duration of 35 ms and pulse delay of 1 ms to 10 s showed that the fraction of paralyzed animals increased up to 80 % with minimum delay. Nevertheless, in the presence of amlodipine with a concentration of 25 nM, almost all Trichoplax remained fast-moving for several minutes despite exposure to voltage waves. Experimental animals showed a total discoordination of motion and could not leave an “electrode trap”, when amlodipine with a concentration of 250 nM was used. Further, Trichoplax plate became rigid, which appeared in animal shape invariability during motion. Finally, amlodipine with a concentration of 50 μM caused a rapid folding of animal plate-like body into a pan in the ventral-dorsal direction and subsequent dissociation of Trichoplax plate into individual cells. In general, the electrical exposure applied demonstrated a cumulative but a reversible physiological effect, which, as expected, is associated with activity of voltage-gated calcium channels. Amlodipine at high concentration (50 μM) caused Trichoplax disintegration; at moderate concentration (250 nM), it disrupted the propagation of activation waves that led to discoordination of animal motion; at low concentration (25 nM), it prevented an electric shock.

Introduction. Nowadays, it is vitally important to develop a method for quantifying melittin not only in apitoxin samples, but also in the products of its processing.The aim of our study is to investigate physical and chemical characteristics of melittin, the main component of apitoxin, as well as the development of methods for the quantitative determination of melittin in the samples of apitoxin and in the pharmaceutical products derived from apitoxin: “Sophia with apitoxin” cream and “Apizartron” ointment.Materials and methods. The objects of the research were apitoxin and melittin, as well as the samples of “Sophia with apitoxin” cream and “Apizartron” ointment satisfying the requirements of regulatory documentation, produced in lots by domestic and foreign manufacturers. The UV spectra of melittin and apitoxin were registered on SF 103 spectrophotometer in quartz cuvettes with 1 cm thickness. The IR spectra were investigated on the IR-instrument of Fourier – FSM-1201 spectrophotometer, LLC “Infraspek”. The determination of melittin purity was carried out by chromatography.Results and discussion. The basic physical and chemical characteristics were established for melittin as a reference sample and the main component of apitoxin. The melting temperature was: (Tmelt.)=190ºС. In the UV-spectrum there could be watched the absorption maxima corresponding to 2 peaks: λ max = 225±2 nm and 285±2 nm were observed. As an analytical wavelength, it is necessary to choose the peak λ =285 nm, since the peak with λ =225 nm is associated with the absorption of light by the internal (shielded) benzene ring of the tryptophan molecule. The nature of the curve and the position of the maxima of the spectra of melittin and the apitoxin solution coincide, which makes it possible to use melittin as a standard for spectrometric quantitative determination of the active substances in apitoxin and preparations based on apitoxin.Conclusion. The worked out spectrophotometric methods for the quantitative determination of melittin in apitoxin has been validated by the indices of specificity, accuracy, detection limit, quantitative determination limit, linearity.

The article presents a new methodological approach to forensic comparison of large amounts of text to establish their similarity/distinctiveness. The proposed approach assumes interaction between a forensic linguist and a forensic examiner with specialized knowledge in the field of forensic computer science, which the effect of optimizing forensic workflow and maximizing objectivity of the resulting expert conclusions.

The 13С/12С isotopic abundances in carbon dioxide of the external environment and carbohydrates synthesized by the plant differ significantly from each other and vary depending on the growing conditions. The differences in the fraction of assimilated 13C are related apparently to the rate of photosynthetic reactions. To carry out the sample preparation for mass-spectrometric isotope analysis of carbon involved in plant life, we developed a new method of sample gasification and experimental setup. А setup provided concentrating carbon dioxide 100 times with catalytic afterburning of organic microimpurities, and the prepared sample was free from residual impurities able to interfere to a level no higher than 10^-5. The gasification method involves the plant glucose oxidation by yeast with the collecting generated carbon dioxide; the concentration of reagents were matched for it. The collected CO2 was ready for isotopic measurements and the level of residual impurities able to interfere was less than 10^-5. The developed sample preparation technique has been used to study the influence of spectral characteristics of the light medium on the exchange of carbon isotopes between atmospheric CO2 and the plant carbon pool.

The article considers the assessment of a long-term personal experience of teaching “History of the Middle Ages” for students specializing in the history of art, and a part of the course devoted to the Middle Ages in the “History of world culture” for students, whose specialisation is “Museology and protection of cultural and natural heritage”. The authors describe the specifics of teaching these courses in the context of students’ acquisition in general, cultural and professional competence.

Obesity during pregnancy increases the risk of obesity in offspring. To correct the offspring development in obese mothers, it is necessary to reveal the molecular mechanisms that mediate the influence of the maternal environment on the offspring ontogenesis. Leptin levels increase with obesity. In C57Bl mice, the Ау mutation is associated with elevated blood levels of leptin in pregnant females and exerts a gender-specific effect on the metabolic phenotype of mature offspring. Aim: to study the influence of Ау mutation on sensitivity to diet-induced obesity in male and female offspring, on fetal and placental weight and on the expression of genes in the placentas of the fetuses of different sexes. Body weight and food intake on a standard and an obesogenic diet, fetal and placental weights on pregnancy days 13 and 18, and gene expression of glucose transporters (GLUT1, GLUT3), neutral amino acid transporters (SNAT1, SNAT2, SNAT4), insulin-like growth factor 2 IGF2 and its receptor IGF2R were measured in male and female offspring of и ɑ/ɑ (control) and Ау/ɑ mothers. Ay mutation influenced the body weight only in male offspring, which consumed a standard diet, and did not influence obesity development in both male and female offspring. The weight of fetuses and placentas in Ау/ɑ as compared to ɑ/ɑ females was reduced on day 13 of pregnancy and was not different on day 18. On day 13 of pregnancy, the mRNA levels of the examined genes did not differ in placentas of male and female fetuses in ɑ/ɑ females. In Ау/ɑ females, the gene expression of GLUT1, GLUT3, SNAT1 and SNAT4 was reduced in female placentas compared to male placentas. The results suggest that the sex-specific transcription response of placentas to elevated leptin levels in pregnant Ау/ɑ females can mediate the gender-specific impact of Ау mutation on the offspring metabolism in postnatal life.

Abstract. The task of the work was to establish the infl uence of the charge state serine determined by the pH value of the medium on kinetic regularities and quantitative characteristics of the process of its anodic oxidation on a platinized platinum electrode. The study was performed by the methods of voltammetry, coulometry, rotating disk electrode and IR-spectroscopy with Fourier transform. As base solutions used 0.1 M NaOH, 0.05 M solution of H2SO4 and acetate buffer with a concentration of salt and acid, 0.5 M and 0.05 M, respectively. The electrode potentials region of the electrochemical conversion of the amino acid was determined. The current of oxidation of anion serine is signifi cantly higher, than cation or zwitterionic form. This can be explained by difference in adsorption activity of anion serine on the surface of platinized platinum. The concentration of the various ionic forms of serine in solution before and after electrooxidation was determined photometrically. It is shown that serine electrooxidation occurs with the participation of 2 electrons in acidic and alkaline environments, whereas zwitterion oxidation is accompanied by 4 electrons transfer. It is established that electrooxidation of serine is carried out from an adsorbed state regardless of solution pH. The possible kinetic scheme of the electrooxidation process is proposed. The rate of electrooxidation of the cation or anion of serine is determined by the stage of transfer of the fi rst electron. The rate of electrooxidation of zwitterion of serine is determined by the stage of transfer of the second electron. Electrooxidation of all ionic forms of serine is kinetically irreversible.

A rare case of angiomyolipoma of a giant-sized vulva in a patient in menopause is described. It is shown that the complex use of ultrasound study, radiography and laparoscopy enable to clarify the diagnosis and optimize the scope of surgical intervention.

When the quality of antibiotics and antibiotic dosage forms cannot be assessed with the help of chemical methods, one can use two variants of the agar diffusion test described in the State Pharmacopoeia XII, part 1 (General pharmacopoeial monograph 42-006807): the three-doses variant of the agar diffusion test and determination with the help of a standard curve. The method is based on directly proportional relationship between the size of test microorganisms inhibition zones and log concentration (dose) of the antibiotic in the solution placed onto agar bacterial medium. The size of the zone depends on a number of factors: sensitivity of the test microorganism to the antibiotic, homogeneity and density of the bacterial lawn, composition of the growth medium, amount of the growth medium placed on Petri dishes, chemical nature of the antibiotic, the dose of antibiotic used in the experiment. Laboratory employees who use this method to test the quality of antibiotics should have appropriate skills. The activity of the drug under testing is determined by comparing it to the established activity of the reference standard which should have compendial quality. Statistical methods are used to assess obtained results and confirm validity of test conditions. The precision of test results is confirmed by computing the 95% confidence interval, and the repeatability is supported by calculation of the relative standard deviation.

The article summarises the results of a study which assessed the response of the cardiovascular system of cats to intravenous administration of the ansamycin class of antibiotics using commercial samples and investigational samples of rifampicin and rifabutin for injections. It was shown that intravenous administration of ansamycin solutions was accompanied by hypotensive effects of varying severity. The increase in the rate of rifampicin administration at a dose of 2.0 mg/0.5 ml/kg can result in a greater decrease of the cat’s blood pressure as compared to the effect caused by the administration of the same dose at a rate described in the monograph 1.2.4.0008.15 «Test for depressor substances». Based on the results of the study a mechanism underlying the observed effect was suggested.

The article investigates the possibility of using thin-layer chromatography and spectrodensitometer analysis of TLC-chromatograms to determine impurities in ciprofloxacin tablets. HPTLC silica gel 60F254 chromatographic plates and the mobile phase dichloromethane:methanol:ammonia:acetonitrile (30:40:20:10) were used to obtain chromatograms that enabled quantitative determination of ciprofloxacin ethylenediamine analogue in the tablet dosage form. The results of testing were consistent with the data obtained by a validated method. The proposed method makes it possible to determine an identified impurity if the data obtained from tests do not comply with the specification.

The article proposes a plan of action for assessing effectiveness and reliability of sterility testing in terms of neutralization of antimicrobial activity of residual amounts of antibiotics remaining on the membrane filters during the analysis. It was demonstrated that the proposed plan of action helps to select appropriate test conditions that rule out the possibility of obtaining false negative results for antibiotics with high biological activity that are capable of sticking to membrane filters. The article demonstrates the need for a stepwise experimental selection of test conditions using different test microorganisms in order to determine a combination of several methods for neutralization of residual amounts of antibiotics which helps to reduce costs, given that satisfactory results may be obtained at any stage depending on the nature of an antibiotic drug. The article explicitly substantiates all stages involved in determination of the completeness of membrane filters cleaning from residual amounts of antibiotics using the example of meropenem. Based on results of experiments test conditions were selected for meropenem products that ensured reliable results of sterility testing.

The article analyses foreign and national recommendations on transfer of methods. It substantiates the need to adequately reproduce test methods that introduce a specific analytical procedure in testing laboratories - in order to be able to give a reliable assessment of the quality of substances and dosage forms. The article gives examples of a successful analytical method transfer, describes ways of transferring analytical procedures, cases when the transfer of method is not needed, and validation/verification parameters that are used to check whether the method is suitable for a particular laboratory. It also gives examples of validation parameters that are used in verification of pharmacopoeial methods, which are chosen based on the type of method and the tested parameter.

In their structure pyrimidin-4-one derivatives are similar to the endogenous nitrogen bases. This makes it possible to predict a wide range of pharmacological activities characteristic for them. The compounds of this series exhibit neurotropic, immunotropic, actoprotective, hypotensive, antihypoxic, anti-infl ammatory and antioxidant activity. Within this framework, the search for and creation of highly effective and safe anti-infl ammatory drugs in the series of N-arylpyrimidin-4(1H)-one is of great current interest.The aim of the work is to carry out predictive studies and targeted synthesis of N-substituted derivatives of pyrimidine-4(1H)-one with anti-infl ammatory activity, as well as toconfi rm the validity of their molecular construction by the results of pharmacological tests.Materials and methods. The research was carried out using the logical-structural approach and information technologies. The computer analysis of biological activity was carried out by the PASS program. Synthesis of the target compounds was carried out using a modifi ed procedure. The structure of the synthesized compounds was confi rmed by 1H NMR, IR and UV spectroscopy. The investigation of the anti-infl ammatory effect of the synthesized compounds was carried out on the model of acute aseptic infl ammation. The synthesized substances were injected intraperitoneally, the magnitude of the edema was the criterion for evaluating the anti-infl ammatory activity.Results and discussion. In the course of the research on the basis of the logico-structural approach, hydroxyphenyl and alkyl derivatives of pyrimidin-4(1H)-one with anti-infl ammatory properties were validated. A preliminary analysis of the pharmacological properties of the predicted structures was carried out using the PASS program and the most promising compounds were selected. To synthesize the tolyl and hydroxyphenyl derivatives of pyrimidin-4(1H)-one, a modifi ed procedure was used. Its essence consists in the use of catalytic amounts of dimethylsulfoxide in order to increase the nucleophilicity of the amine component of the reaction. In order to confi rm the reliability and expediency of the molecular construction, the antiexudative activity of the target compounds was studied.Conclusion. The results of pharmacological studies indicate the prospect of searching for and creating new biologically active compounds having anti-infl ammatory activity among the tolyl and hydroxyphenyl derivatives of pyrimidin-4(1H)-one.

Multidisciplinary studies have allowed us to describe the abiotic landscapes and, thus, reveal the ichnological and benthic foraminifera trends in a deep-water gateway. Mesoscale landscape mapping is presented based on the bathymetric position index, substrate types and near-bottom water temperature. Four sediment cores, retrieved from the entrance, centre and exit of the gap, were subject to computed tomography, ichnological and benthic foraminifera studies. A high diversity of abiotic landscapes in the relatively small area of Discovery Gap is detected and its landscape is characterized by 23 landscape types. The most heterogeneous abiotic factor is a topography that is associated with sediment patchiness and substrate variability. The ichnological and tomographical studies of the sediment cores demonstrate lateral and temporal differences in the macrobenthic tracemaker behaviour. The ichnofossils assemblage of the sediment core can be assigned to the Zoophycos ichnofacies with a higher presence of Zoophycos in the entrance site of the gap and during glacial intervals. Higher benthic foraminifera diversity and species richness during the Holocene are also registered in the southern part of the gap compared to the northern part. The spatial and temporal differences in macro-benthos behavior and benthic foraminifera distribution in the deep-water gateway are proposed to relate to the topographical variations of the Antarctic Bottom Water and its influence on the hydrodynamic regime, nutrient transport, etc.