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We investigate the possibility of using induction currents for improving the reliability of thermal power plants by increasing the corrosion resistance of internal surfaces of power-generating equipment, such as heating surfaces of boiler units. Corrosion resistance can be enhanced by improving the strength of an oxide film formed during passivation (oxidation). In this work, the oxide film strength was increased by electrochemical passivation of metal surfaces with induction currents. Using the method of multidimensional mathematical modeling of multi-parametric and multi-functional processes, we established that, for a continuous-loop economizer of a steam boiler comprising steel pipes with an inner diameter of 32 mm (24 coils operated simultaneously), an aqueous oxidant (oxygen) solution should be passed through the entire system of pipes for 4 h at an alternating current of 25 A. Under this treatment, oxygen should be added into the aqueous solution at a temperature of 130–450°C, an oxygen concentration of 1 g/kg, and a water flow rate of 0.5–5.0 m/s. Treatment intervals should be determined depending on the operating conditions of the equipment: reset, shutdown, or preservation. The efficiency of the method depends on the electric current passed over metal surface, treatment duration, oxidant concentration, as well as the type and size of the treated metal surface. The proposed passivation method can be used in both drum boilers and single-pass boilers. For example, it is recommended that passivation of water walls be carried out during boiler warm-up operation at 30–40% of boiler load, as well as passivation of superheat surfaces of boiler units and economizers. Therefore, the use of electrochemical passivation can increase the corrosion resistance of metal surfaces of power-generating equipment at thermal power plants.

The condensation of 3-arylhydrazinylidenepentane-2,4-diones with hydrazine hydrate, 2-hydroxyethylhydrazine, benzylhydrazine hydrochloride, and 4-hydrazinylbenzenesulfonamide hydrochloride gave 4-aryldiazenyl-3,5-dimethylpyrazoles. An alternative route to the synthesis of N-substituted 4-aryldiazenylpyrazoles is based on the alkylation of NH-pyrazoles with haloalkanes. The synthesized compounds were tested for antimicrobial activity against eight pathogenic dermatophytes, yeast-like fungi of the Candida genus and the bacteria Neisseria gonorrhoeae. The structure—activity relationship analysis showed that 4-tolyldiazenylpyrazoles bearing H, AcO(CH2)4, or HO(CH2)4 substituents at the N(1) atom have the highest mycostatic activity against all the dermatophyte strains under study. However, 4-aryldiazenyl-3,5-dimethylpyrazoles proved to be quite cytotoxic against the McCoy B cell line.

We studied different approaches to the synthesis of polyfluoroalkyl-containing 1-methyl-4-nitrosopyrazoles, which are based on the cyclization of 4,4,4-trifluoro-3,3-dihydroxy-2-hydroxyimino-1-R-butan-1-ones or 2-hydroxyimino-1,3-diketones with methylhydrazine and on a one-pot sequential treatment of 1,3-diketones with sodium nitrite and methylhydrazine. It was found that the regioselectivity of the formation of 1-methyl-4-nitrosopyrazoles is affected by the steric factors of 1,3-dicarbonyl reagents. The study of the mycostatic effect of 4-nitrosopyrazoles showed that the introduction of a bulky polyfluoroalkyl or tert-butyl substituent leads to a decrease in their activity.

The results of a study of the unoccupied electronic states of ultrathin films of bis-carboxyphenyl-phthalide (DCA-DPP) and bis-methylphenyl-phthalide (DM-DPP) up to 8 nm thick are presented. The studies are carried out by total current spectroscopy (TCS) in the energy range from 5 to 20 eV above EF during thermal vacuum deposition of these organic films on the surface of highly ordered pyrolytic graphite (HOPG). The values of Evac relative to EF, i.e., the work function of electrons of the DM-DPP films at a film thickness of 5–8 nm are found to be 4.3 ± 0.1 eV. The values of the work function of electrons of the DCA‑DPP films are found to be 3.7 ± 0.1 eV. The structure of the maxima of unoccupied electronic states of DCA-DPP and DM-DPP films in the studied energy range is established. A comparison of the obtained properties of DCA-DPP and DM-DPP films with the properties of films of molecules of unsubstituted diphenylphthalide (DPP) is presented. Thus, the –CH3 substitution of the DPP molecule has almost no effect on the height of the potential barrier between the film and the HOPG surface, while –COOH substitution of the DPP molecule leads to an increase in the height of the potential barrier between the film and the HOPG substrate surface by 0.5–0.6 eV. Substitution of DPP molecules with –COOH functional groups and, thus, the formation of DCA-DPP molecules lead to a shift of two maxima of the fine structure of the total current spectra located at energies in the range from 5 to 8 eV above EF by about 1 eV towards the lower electron energies.

Unoccupied electronic states in the energy range from 5 to 20 eV above the Fermi level have been studied in ultrathin films of dimethyl-substituted thiophene–phenylene cooligomers CH3-phenylene–thiophene–thiophene–phenylene–CH3 (CH3–PTTP–CH3) on polycrystalline gold surfaces of two types: the ex situ Au layer thermally deposited in a special chamber and the in situ Au surface prepared inside an analytical chamber. The film structure is studied by the X-ray diffraction (XRD) method. The formation of a superposition of the amorphous phase and the crystalline phase with period 3.8 nm is discussed. The energy positions of the maxima of the unoccupied electronic states and the character of formation of the boundary potential barrier have been studied by the total current spectroscopy (TCS). The structures of the FSTCS maxima of the 5–7-nm-thick CH3–PTTP–CH3 films are not different when using various types of Au substrates and the ZnO semiconductor surface prepared by atomic layer deposition (ALD). As a CH3–PTTP–CH3 layer is deposited on the ex situ Au and in situ Au surfaces, the electron work function increases insignificantly (by ~0.1 eV) as the coating thickness increases to 5–7 nm. At such thicknesses of the CH3–PTTP–CH3 films, the electron work function is 4.7 ± 0.1 eV in the case of the ex situ Au substrate and 4.9 ± 0.1 eV in the case of the in situ Au substrate. A possible influence of the processes of physicochemical interaction at the boundary between the film and the substrate on the formation of the boundary potential barrier in the structures under study is discussed.

New N-substituted enamino ketones were synthesized by directed transformation of 3-acetyl- and 3-benzoyl-5,6,7,8-tetrafluoro-4H-chromen-4-ones by the action of highly basic primary amines as a result of opening of the pyranone ring and deacylation. The synthesizedN-hexyl and N-octyl derivatives were evaluated for fungistatic and bacteriostatic activities.

This paper presents the results of a comparative study of the composition of asphaltenes of two heavy oils and liquid products of their conversion in a supercritical hexane (SCH) stream. Using elem...

A comparative study has been performed for the structures of the maxima of the density of unoccupied electronic states (DOUS) in ultrathin films of the naphthalene-1,4,5,8-tetracarboxyl acid dianhydride (NTCDA) and naphthalene-1,8-dicarboxyl acid anhydride (NDCA) and two types of films based on phthalides: 3,3-diphenylphthalide (DPP) and 3,3-diphenylphthalide-4',4'-dicarboxyl acid (DPP–DCA). The structures of unoccupied electronic states of the 8–10-nm-thick films have been measured by total current spectroscopy (TCS) in the energy range from 5 to 20 eV above the Fermi level. The experimental results are analyzed by constructing the model total current spectra and the DOUS dependences using the results of calculation of the orbital energy of the molecules under study by the density functional theory (DFT) at the B3LYP/6-31G(d) level. The difference in the DOUS spectra of the NTCDA and NDCA films is the shift of the main DOUS maxima of the NTCDA film to lower energies approximately by 1 eV at energies lower than 12.5 eV; at higher energies, the DOUS maxima are shifted by 1.5–2 eV. The energy positions of the maxima of the total current spectra of the DPP–DCA and DPP films are changed only slightly as various substrates are used: highly ordered pyrolitic graphite (HOPG) and a CdS deposited layer-by-layer. The relative intensities of the maxima are different as various substrates are used. The characteristic shifts of the maxima of the total current spectra of the DPP–DCA films are approximately 1 eV at energies lower 12.5 eV above the Fermi level and 1.5–2 eV at higher energies, as compared to the positions of the corresponding maxima of the DPP films.

Gossypol is a highly active compound with antiviral, antioxidant, antimicrobial, antimalarial, and antitumor properties. It is known that the antitumor effect of gossypol is associated with genotoxicity; however, gossypol interaction with chromatin was not studied. In this work, using the method of single particle microscopy based on the Forster resonant energy transfer, it was found that gossypol at concentrations of 10 μM and higher causes significant structural changes in the conformation of nucleosomal DNA on the histone octamer. These changes affect at least 35 bp of nucleosomal DNA, increase the distance between neighboring superhelical gyres of nucleosomal DNA in this region to 9 nm or more, and are caused by unwrapping of nucleosomal DNA. The presence of linker DNA regions slightly increases the resistance of nucleosomes to the gossypol action compared with core nucleosomes. At the concentration of 30 μM and higher, gossypol completely disrupts the structure of nucleosomes, causing dissociation of histones from DNA. The obtained data indicate that gossypol genotoxicity observed in vivo could be associated with a direct effect of gossypol on chromatin, leading to disruption of the nucleosome structure.

The formation of unoccupied electronic states and the boundary potential barrier during thermal deposition of tetracyanoquinodimethane (TCNQ) films to 7 nm in thickness on a (SiO2)n-Si surface has been studied. The electronic characteristics of the surface under study are measured by the total current spectroscopy (TCS) using a testing electron beam with energies from 5 to 20 eV above the Fermi level. The formation of a boundary potential barrier in the (SiO2)n-Si/TCNQ structure is accompanied by an increase in the work function of the surface from 4.2 ± 0.1 to 4.7 ± 0.1 eV. Using the results of the TCS experiments, the DOUS dependences of the TCNQ films have been built. To analyze the experimental DOUS dependences, the orbital energies of the TCNQ molecules are calculated by the density functional theory (DFT) at the B3LYP/6-31G(d) level with subsequent correction and the inclusion of the polarization energy of the condensed medium. In the energy range indicated above, DOUS of the TCNQ films has four main maxima. The DOUS maximum at energy 7.0 eV above EF is predominantly formed by π* orbitals. Three DOUS maxima in the energy range from 8.0 to 20 eV above EF are formed by approximately the same amount of the π* and σ* orbitals.

The antioxidant capacity (AOC) of water–alcohol tinctures of medicinal plant materials, vitamins, and vitamin complexes was investigated. The accuracy indicators for determining the antioxidant capacity of these samples are found; the accuracy of the measurement results is examined using a sample of ascorbic acid with a known concentration of the main component. The relative measurement error of the antioxidant capacity of herbal and synthetic medications does not exceed 10%.

Nucleophilic substitution and 1,3-dipolar cycloaddition reactions were used to synthesize 3,6-disubstituted derivatives of simm-tetrazine containing azolyl, aminoalkyl, and oxyalkyl fragments. The antibacterial activity of the resulting compounds was studied using the obligate pathogen Neisseria gonorrhoeae and opportunistic pathogenic microorganisms, while antifungal activity was assessed using anthropo- and zooanthropophilic dermatophytes.

A series of new 5-aryl-2,2'-bipyridines and their (polyfluoro)salicylate complexes of Cu(II), Co(II) and Mn(II) were synthesized. Their antimicrobial activity was evaluated in vitro against six strains of Trichophytons, E. floccosum, M. canis, C. ablicans and Gram-negative bacteria N. gonorrhoeae. Among azo-ligands, Ph-bipy and Tol-bipy showed promising antifungal activity (minimum inhibitory concentration (MIC)

Poly(ADP-ribose) polymerase 1 (PARP1) is an enzyme involved in DNA repair, chromatin organization and transcription. During transcription initiation, PARP1 interacts with gene promoters where it binds to nucleosomes, replaces linker histone H1 and participates in gene regulation. However, the mechanisms of PARP1-nucleosome interaction remain unknown. Here, using spFRET microscopy, molecular dynamics and biochemical approaches we identified several different PARP1-nucleosome complexes and two types of PARP1 binding to mononucleosomes: at DNA ends and end-independent. Two or three molecules of PARP1 can bind to a nucleosome depending on the presence of linker DNA and can induce reorganization of the entire nucleosome that is independent of catalytic activity of PARP1. Nucleosome reorganization depends upon binding of PARP1 to nucleosomal DNA, likely near the binding site of linker histone H1. The data suggest that PARP1 can induce the formation of an alternative nucleosome state that is likely involved in gene regulation and DNA repair.

Long-distance interaction plays an important role in the regulation of eukaryotic genes. Chromatin structure is involved in the process, but the role of histone modifications has not been studied. In the present work, the role of acetylation Н4K16 (Н4K16-Ac) to enhancer-promoter communication (EPC) was analyzed. This modification is associated with euchromatin and is involved in the decompaction of chromatin fibers. We have shown that the effect of H4K16-Ac on EPC in vitro depends on the level of chromatin assembly. EPC in chromatin, which lacks nucleosomes at random positions on DNA, is inhibited in the presence of H4K16-Aс. At the same time, EPC in chromatin, in which nucleosomes occupy all available positions on DNA, is somewhat stimulated in the presence of H4K16-Aс.

The results of diagnostics of the atomic composition of a diphenylphthalide (DPP) film thermally precipitated in vacuum by the of X-ray photoelectric spectroscopy (XPS) method are presented. The results of examination of the unoccupied electronic states of the ultrathin DPP films with the thickness up to 10 nm on the surface of the highly oriented pyrolytic graphite (HOPG) by the total current spectroscopy (TCS) method in the energy range from 5 to 20 eV above EF are presented. In this range, the main maxima in the total current spectra are identified. The analysis of the TCS results with consideration of the theoretical calculation results has shown that the low-energy maxima observed at the energies from 6 to 7.5 eV are induced predominately by π* electron orbitals of DPP films. The values of the energy Evac in relation to EF, i.e., of the electron work function in the DPP films at the film thickness of 5–10 nm, are found experimentally at a level of 4.3 ± 0.1 eV. The negative charge transfer from an organic film to the substrate corresponds to the formation of the HOPG/DPP boundary potential barrier during the thermal deposition of the DPP film.

A total of 166 patients (72 males and 94 females) with insulindependent diabetes mellitus (IDDM) aged 5 to 21 years with disease duration of 1 to 18 years were examined in order to assess the clinical picture and epidemiology of diabetic nephropathy (DN) in children and adolescents in Moscow. Microalbuminuria (MAU)*was the criterion of DN. DN was diagnosed in 75 (45.7%) of patients: in 64 (85.3%) at the MAU stage and in 11 (14.6%)) at the stage of proteinuria. There were no cases with the nephrotic syndrome or chronic renal insufficiency. The minimal duration of IDDM in adolescents with MAU was about 2 years, in those with proteinuria about 5 years. All patients with DN were pubertal or postpubertal. The incidence of DN did not depend on the sex, age, or pubertal status. DN risk factors in these patients were chronic hyperglycemia, total and prepubertal duration of diabetes, hereditary predisposition to arterial hypertension, and lipid disorders. Therefore, prepubertal children with disease duration of 5 years and adolescents with disease duration of 1 year since IDDM manifestation are to be screened for DN.

The complex of physicochemical methods of analysis (elemental analysis, cryoscopy in benzene, IR and ¹H NMR spectroscopies, structural group analysis, gas chromatography–mass spectrometry, and selective chemical cleavage of sulfide and ether bonds) is used to comparatively characterize resins and asphaltenes of light and heavy oils. Attention is paid to the study of their structural group composition and the composition of moieties bound in molecules of resin–asphaltene substances (RAS) through ether and sulfide bridges, as well as the composition of compounds occluded by asphaltene molecules and nitrogen bases of resins. It is found that resins and asphaltenes of the heavy oil are characterized by higher average molecular masses and large overall sizes of mean molecules, due to the increased content of aromatic cycles in the naphthenic–aromatic system. The similar sets of linear and branched alkanes, alkylcyclopentanes, alkylcyclohexanes, steranes, mono- and disubstituted alkylbenzenes, and dibenzothiophenes identified in occluded compounds and products of chemolysis of resins and asphaltenes under study suggest the presence of most of these compounds as structural fragments in RAS molecules of light and heavy crude oils under study. Alkyl-substituted quinolines and benzoquinolines are identified in the nitrogen bases of resins. The feature of the light oil is the presence of “sulfur-bound” alkenes and polycycloalkenes in the structure of its asphaltenes. The findings expand our understanding of the structure of petroleum resins and asphaltenes. They can be used to simulate their structure in developing new controlled methods for processing hydrocarbon feedstock.

Reactions of quinoxalines and quinoxalin-2-ones with C-nucleophiles under acid-catalysis conditions gave products from nucleophilic substitution of hydrogen. Substitution of F atoms in the aromatic core of quinoxalines was studied. Antibacterial and fungistatic activity of the synthesized compounds was studied.

Perfusion scintigraphy of the myocardium was carried out with the help of the Millennium MG gamma camera (USA) in synchronization with the ECG in 141 patients aged of from 5 to 15 years. Patients were divided into four groups: 30 chronic myocarditis (CM) patients, 30 hypertrophic cardiomyopathy (HCMP) patients, 30 dilated cardiomyopathy (DCMP) cases and 21noncompact cardiomyopathy (NCMP) patients. The left ventricular (LV) ejection fraction was established to be preserved in CM and HCMC patients (in cases without signs of obstruction), a significant reduction in the ejection fraction was found in NKMP and DCMP patients. The thickness of the myocardium of the LV significantly increased only in HCM patients. The expansion of the LV cavity was detected in all patients, but its decrease was present only in HCM cases. The contractility of the myocardium was impaired in all the patients examined. Disturbances of the myocardial perfusion were the most pronounced in NKMP and DCMP patients. Signs of fibrosis were detected in most patients, but HCM patients. In 40% of CM patients, scintigraphic signs of inflammation were determined. In 17% of all examinations there was noted hyperperfusion of the right ventricular myocardium. The authors believe myocardial tomoscintigraphy to be the unique method for analyzing myocardial viability in various forms of cardiac pathology that can be used for the evaluation of the effectiveness of the treatment.

The atomic composition of films of a polyphenol antioxidant, namely, resveratrol (RVL), with a thickness of up to 50 nm thermally deposited on an oxidized silicon surface is studied by the method of X-ray photoelectron spectroscopy (XPS). It is found that the surface area of pores in the RVL film is about 15% of the total surface area. The results of studying the stability of the RVL films when their surface is treated with Ar+ ions of 3 keV under the electric current of 1 μA passing through the sample for 30 s are given. The treatment gives rise to an increase in the area of pores to 30–40%, while the ratio of the concentration of C atoms to the concentration of O atoms in the RVL film both before and after the treatment of the surface with ions does not correspond to the chemical formula of RVL molecules. Using the method of atomic force microscopy (AFM) in contact mode with a scanning area size of about 10 × 10 μm, RVL coatings deposited on the oxidized silicon and polycrystalline Au surfaces are studied. It is found that the RVL films produce grainy and porous coatings on the substrate surfaces. The typical size of grains in the sample surface plane is 150–300 nm, and the characteristic elevation reaches 30 nm.

Герасимова Нина Павловна - кандидат юридических наук, доцент кафедры теории государства и права, конституционного и административного права, Южно-Уральский государственный университет, г. Челябинск. Nina Pavlovna Gerasimova - Candidate of Sciences (Law), Associate Professor of the Theory of State and Law, Constitutional and Administrative Law, South Ural State University, Chelyabinsk, Russian Federation.

The reaction of azoloannulated [1,2,4,5]tetrazines with guanidine was studied. New 3-guanidinoimidazo[1,2-b]- and 6-guanidino[1,2,4]triazolo[4,3-b] [1,2,4,5]tetrazines were synthesized using the nucleophilic substitution methodology. Compounds with high antibacterial and antiglycation activity were revealed.

Background: Liquid-liquid phase separation (LLPS) that leads to the formation of temporary functional domains in cells plays an important role in the processes of chromatin condensation and gene regulation. Earlier, it was demonstrated that histone H1.4 can form LLPS droplets with DNA. In the present work, LLPS was studied for histone H1.0, which is mainly expressed in differentiated and non-dividing cells. H1.0 is involved in cancer development: its amount decreases with the progression of tumor cells to malignancy. Methods: LSM710 confocal microscope (Zeiss) equipped with the 40x/1.2W objective was used to image mixtures of H1.0 with Cy3/Cy5 labeled DNA or nucleosomes in fluorescent and transmitted-light channels at the excitation of 514 nm. The formation of condensates as a result of LLPS was confirmed by salt-jump and FRAP/FLIP experiments. Results: Condensates were not observed when the ratio of negative to positive charges (N/P) in the samples was >1. At N/P~0.7, optically homogeneous droplet-like condensates were found. The appearance of condensates, their size and shape depended on concentrations of H1.0 and DNA. LLPS condensates but not aggregates disappeared by salt-jump to 650 mM NaCl. FRAP/FLIP experiments revealed a moderate rate of fluorescence recovery (τ½22s) indicating moderate DNA mobility of the H1.0-mediated condensates. The appearance of condensates was also observed in the mixtures of H1.0, DNA and Cy3/Cy5-labeled nucleosomes. Nucleosomes were involved in the condensate formation and found to be 2-fold more mobile (τ½10 s) than DNA. Conclusion: LLPS-related properties of H1.0 were studied for DNA and nucleosomes in vitro. Comparison with H1.4 shows that H1.0 forms liquid condensates of approximately the same size. Our result also may indicate that chromatin retains pronounced dynamic properties in H1.0-induced droplets despite the fact that H1.0 induces the formation of more compact chromatin.

4-Nitroso-3-trifluoromethyl-5-alkyl[(het)aryl]pyrazoles were synthesized via one-pot nitrosation of 1,3-diketones or their lithium salts followed by treatment of hydrazines. Reduction of nitroso-derivatives made it possible to obtain 4-amino-3-trifluoromethylpyrazoles chlorides. According to computer-aided calculations, all synthesized compounds are expected to have acceptable ADME profile for drug design. Tuberculostatic, antibacterial, antimycotic, antioxidant and cytotoxic activities of the compounds were evaluated in vitro, while their analgesic and anti-inflammatory action was tested in vivo along with acute toxicity studies. N-Unsubstituted 4-nitrosopyrazoles were the most effective tuberculostatics (MIC to 0.36 μg/ml) and antibacterial agents against Streptococcus pyogenes (MIC to 7.8 μg/ml), Staphylococcus aureus, S. aureus MRSA and Neisseria gonorrhoeae (MIC to 15.6 μg/ml). 4-Nitroso-1-methyl-5-phenylpyrazole had the pronounced antimycotic action against a wide range of fungi (Trichophyton rubrum, T. tonsurans, T. violaceum, T. interdigitale, Epidermophyton floccosum, Microsporum canis with MIC 0.38–12.5 μg/ml). N-Unsubstituted 4-aminopyrazoles shown high radical-scavenging activity in ABTS test, ORAC/AAPH and oxidative erythrocyte hemolysis assays. 1-Methyl-5-phenyl-3-trifluoromethylpyrazol-4-aminium chloride revealed potential anticancer activity against HeLa cells (SI > 1351). The pronounced analgesic activity was found for 4-nitroso- and 4-aminopyrazoles having phenyl fragment at the position 5 in “hot plate” test. The most of the obtained pyrazoles had a moderate acute toxicity.

7-Methylguanine (7-MG), a natural compound that inhibits DNA repair enzyme poly(ADP-ribose) polymerase 1 (PARP-1), can be considered as a potential anticancer drug candidate. Here we describe a study of 7-MG inhibition mechanism using molecular dynamics, fluorescence anisotropy and single-particle Förster resonance energy transfer (spFRET) microscopy approaches to elucidate intermolecular interactions between 7-MG, PARP-1 and nucleosomal DNA. It is shown that 7-MG competes with substrate NAD+ and its binding in the PARP-1 active site is mediated by hydrogen bonds and nonpolar interactions with the Gly863, Ala898, Ser904, and Tyr907 residues. 7-MG promotes formation of the PARP-1−nucleosome complexes and suppresses DNA-dependent PARP-1 automodification. This results in nonproductive trapping of PARP-1 on nucleosomes and likely prevents the removal of genotoxic DNA lesions.

The synthesis of bis(salicylato)Cu(II) and Co(II) chelates based on methyl trifluorosalicylate and the corresponding M(OAc) 2 in the presence of alkali is reported. The following reaction with 2,2’-bipyridine and 1,10 phenanthroline in refluxing methanol affords heteroligand complexes containing methyl trifluorosalicylate and azaheterocyclic ligands in the ratio 2:1. However, the refluxing of Co(II) chelates in ethanol resulted in transesterification of methyl ester group to form heteroligand complexes of ethyl trifluorosalicylate while Cu(II) chelates underwent hydrolysis of ester group to obtain heteroligand complexes of trifluorosalicylic acid. The structures of obtained metal complexes were confirmed by X-Ray diffraction experiment, IR spectroscopy and elemental analysis. The antimycotic and antibacterial activities of synthesized metal complexes were investigated. The heteroligand metal complexes were found to exhibit moderate anti-Candida albicans activity. Among new series of complexes, the most activity showed the mixed metal complexes of trifluorosalicylates and 1,10-phenanthroline revealing a wide range of action in relation to pathogenic fungi and bacteria.

The effect of high molecular weight nitrogen-containing bases of various structures and oxygen-containing acidic compounds of a high-paraffin oil on the precipitation of its asphaltenes from model toluene : hexane (1 : 3) solutions and solutions containing natural inhibitors is studied using the spectrophotometric method. The intrinsic aggregative stability of solutions of bases and acidic compounds is also determined.

The composition and structure of nitrogen-containing bases isolated from the maltene fraction of the liquid products of conversion of asphaltenes of bituminous oil from the Ashalchinskoye oilfield in a supercritical hexane stream at 450°C and 15 MPa are investigated. It is shown that they are represented by a mixture of high molecular weight and low molecular weight compounds, where high molecular weight components prevail. Compared to the initial asphaltenes, their mean molecules are characterized by smaller sizes associated with a decrease in the number of structural blocks (ma = 2.3 versus 3.4), in the composition of which the number of saturated cycles is significantly reduced (Rn* = 2.8 versus 6.0). The size of the aromatic core remains virtually unchanged. (Ra* = 2.9 versus 3.4). At the same time, the internal arrangement of aromatic cores in the naphthenoaromatic system of the structural block (Cα* = 4.5 and 5.6) is preserved, which causes a high degree of screening of the nitrogen atom and, as a consequence, thermal stability of the compounds. Using the GC–MS method, C2−C6 quinolines, C2−C4 benzoquinolines, C1 dibenzoquinolines, and C16H33NO, C18H35NO, C18H37NO aliphatic amides have been identified in the nitrogen-containing bases of maltenes.

The results of studies of asphaltenes of bituminous oil from the Ashalchinskoye oilfield and oil and resin-asphaltene components isolated from the liquid products of their conversion in n-hexane under supercritical conditions are presented. It is found out that the mean molecules of secondary asphaltenes and resins differ from those of asphaltenes of the initial sample by the number of structural blocks. They prevail in the mean molecule of secondary asphaltenes, while in the mean molecule of resins they are lesser in number. A feature of the structural blocks of secondary asphaltenes is a lower number of naphthenic cycles, a higher content of sulfur atoms, and a reduced content of nitrogen and oxygen atoms. The structural blocks of the resulted resins consist of minority of aromatic and naphthenic cycles and contain a lesser number of sulfur and nitrogen atoms but more of oxygen atoms than the initial and secondary asphaltenes. The qualitative composition of the compounds identified in the resulted oils is substantially identical to that of the compounds identified in oil components isolated from liquid products of autoclave thermal degradation of asphaltene substances of heavy oils.

A procedure was developed for the preparation of a stalled elongation complex of Escherichia coli RNA polymerase with the nucleosome for investigation by cryo-electron microscopy. We purified the complex from the excess of free RNA polymerase and unproductive complexes on heparin resin and concentrated it on an affine monolayer formed by lipids bound to Ni ions. The use of affinity grids with an immobilized lipid monolayer helps to prevent aggregation of the particles on the grid surface. This technique can be used in the future to obtain a three-dimensional reconstruction of the EC+39 elongation complex.

The unoccupied electron states and the boundary potential barrier during deposition of ultrathin films of dimethyl-substituted thiophene–phenylene coolygomers of the type of CH3–phenylene–thiophene–thiophene–phenylene–CH3 (CH3–PTTP–CH3) on an oxidized silicon surface have been studied. The electronic characteristics have been measured in the energy range from 5 to 20 eV above the Fermi level using total current spectroscopy (TCS). The structure of the CH3–PTTP–CH3 film surfaces has been studied by atomic force microscopy (AFM), and the atomic compositions of the films have been studied by X-ray photoelectron spectroscopy (XPS). The changes in the maximum intensities measured by the TCS method obtained from the deposited CH3–PTTP–CH3 film and from the substrate during increasing in the organic coating thickness to 6 nm is discussed. The formation of the boundary potential barrier in the n-Si/SiO2/CH3–PTTP–CH3 is accompanied by the decrease in the surface work function from 4.2 ± 0.1 to 4.0 ± 0.1 eV as the organic coating thickness increases to 3 nm. The ratio of atomic concentrations C: S in the CH3–PTTP–CH3 films well corresponds to the chemical formula of CH3–PTTP–CH3 molecules. The roughness of the CH3–PTTP–CH3 coating surface was not higher than 10 nm on the ~10 × 10 μm areas as the total CH3–PTTP–CH3-layer thickness was about 100 nm.

Nhp6A is a small nonhistone chromosomal yeast protein that binds DNA nonspecifically. This protein is present at many promoters and transcribed regions of the genome and is involved in regulation of transcription. Recently, Nhp6A was shown to participate in destabilization of the nucleosome structure. This may explain its location at regulatory sites. However, its function in the coding regions remains unknown. In this study, in order to identify the mechanisms of Nhp6A action, we examined genomic associations of the Nhp6A protein along the entire length of the target genes, including the open reading frame. We found that Nhp6A predominantly binds to the coding regions of short GC-rich yeast genes. The observed interaction is not associated with the high GC content in these DNA loci. Thus, we can propose a specific regulatory mechanism involving Nhp6A for this group. Since a large number of the studied genes retain features of the ancestral bacterial genome, we suggest that this group can be defined as “ancient.” Presumably, this genomic distribution of Nhp6 is related to the mechanisms of regulation of gene transcription that appeared early in the course of evolution.

The results of examination of the electronic structure of the conduction band of naphthalenedicarboxylic anhydride (NDCA) films in the process of their deposition on the surface of oxidized silicon are presented. These results were obtained using total current spectroscopy (TCS) in the energy range from 5 to 20 eV above the Fermi level. The energy position of the primary maxima of the density of unoccupied states (DOUS) of an NDCA film was determined based on the experimental TCS data and calculated data and compared with the position of the DOUS maxima of a naphthalenetetracarboxylic dianhydride (NTCDA) film. The theoretical analysis involved calculating the energies and the spatial distribution of orbitals of the molecules under study at the B3LYP/6-31G(d) DFT (density functional theory) level and correcting the obtained energies in accordance with the procedure that was proven effective in earlier studies of the conduction band of films of small conjugated organic molecules. It was found that the DOUS maxima of the NTCDA film in the studied energy interval from 5 to 20 eV above the Fermi level are shifted toward lower electron energies by 1–2 eV relative to the corresponding DOUS maxima of the NDCA film Subdivision of the Ufa Federal Research Centre of the.

Introduction. Currently, there are different views on the treatment of non-parasitic spleen cysts in children. The choice of method of treatment is under discussion. The aim of our study was to evaluate and analyze the immediate and long-term results of surgical interventions performed on nonparasitic spleen cysts in children. Material and methods. There are presented results of surgical treatment of the 21 patient, who was on treatment at the Department of Abdominal Surgery of the Russian Children Clinical Hospital over the period from 2013 to 2016. Patients were examined by means of ultrasound of the abdominal cavity, CT, MRI. All patients have been operated. 22 surgical interventions were performed by using laparoscopic access, out of which 2 partial resections of the spleen, 1 splenectomy, 19 fenestrations of spleen cysts.Results. During the course of the operation and in the immediate postoperative period there were no complications. Patients were observed for the period of from 1 year to 3 years. Good results of treatment were obtained in 20 (95.2%) children. In a long-term period a relapse occurred in the one patient one year after the operation. The patient was reoperated, splenectomy was performed. Conclusion. The surgical treatment of spleen cysts is the basic one. It is indicated for cysts sized larger than 5 cm and cysts with clinical symptoms. Minimally invasive interventions in children are optimal because of their low traumatism and good cosmetic effect. Our study showed a high efficiency of laparoscopic operations in children suffered from non-parasitic spleen cysts with good long-term results.