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The present work investigates the thermochemical conversion of wheat straw biomass in a suband supercritical tetralin medium. The experiment was carried out in a batch reactor at 285, 330, 380, 420 and 460 °C for 10 minutes. The process of straw liquefaction in subcritical tetralin was characterised by relatively high efficiency. At 420 °C, the biomass conversion rate amounted to 98.2% a.d.m. The maximum yield of liquid products during liquefaction (81.6% a.d.m.) was obtained at 380 °C. The liquid products were fractionated by successive extraction with hexane, water and ethanol. According to GC-MS data, the liquefaction products soluble in hexane comprised a mixture of low-molecular weight degradation products of straw components and tetralin derivatives, including methyl esters of fatty acids, aromatic compounds, alkanes and minor alcohols and ketones. When the process temperature increased, the content of esters diminished, followed by an increment in the proportion of aromatic compounds up to 50% rel. No esters and phenolic compounds were present in the liquefaction products soluble in hexane obtained at 460 °C. Dehydrogenation, alkylation and isomerisation of tetralin with the formation of naphthalene, 1,4-dihydronaphthalene and alkyl derivatives of tetralin, naphthalene and indane occurred under the given conditions. The conducted comparative analysis of infrared spectra for straw and solid products of liquefaction suggested that, at temperatures of up to 330 °C, the process of polysaccharide fragmentation is more pronounced in the straw biomass, while, at higher temperatures, the process of lignin fragmentation prevails. As a result, the IR-spectrum of the solid product obtained at 380 °C revealed weakly pronounced absorption bands of alkylaromatic structural fragments. At the same time, only the absorption bands of mineral components in straw ash and adsorbed water were observed in the IR-spectrum of the solid product obtained at 420 °C.

Introduction. Increased arterial stiffness is one of the key links in the formation of cardiovascular pathology in older age groups. At the same time, the effect of vascular stiffness on myocardial function in cardiac patients with frailty remains insufficiently studied.Aim of study. Тo analyze the data of arterial stiffness and diastolic function of left ventricle (LV) in patients older than 65 years with arterial hypertension and frailty.Materials and methods. The study included 90 outpatient and inpatient patients older than 65 years with the presence of arterial hypertension. All patients were divided into two groups: with the presence and absence of frailty. To identify frailty, we used the questionnaire “Age is not a hindrance”, a short battery of physical activity tests. Methods of volumetric sphygmometry, echocardiography, including tissue Doppler were used. The obtained data were analyzed using a package of statistical programs.Results. The results of a comparative simultaneous non-randomized descriptive study of two groups of patients are presented. The study found that the systolic function, diastolic dysfunction of the left ventricle by the type of slowing down of LV relaxation in both groups did not significantly differ in their indicators. In the group of patients with frailty, LV diastolic dysfunction was significantly more often detected by the type of pseudonormalization – with an increase in filling pressure. When analyzing data of arterial stiffness, differences were obtained in both groups in the left cardio-ankle vascular index (LCAVI), systolic blood pressure (LB SAD), pulse pressure (LB PD) in the left shoulder area, and the delta of average blood pressure in the left ankle area (LA% IDA), which were significantly higher in patients with frailty.Conclusion. In the group of patients with hypertension older than 65 years with frailty, a violation of the LV diastolic function by the type of pseudonormalization with an increase in filling pressure prevails. An increase in filling pressure in the group of patients older than 65 years with hypertension and the presence of frailty is associated with an increase in the complex of indicators characterizing arterial stiffness – the cardio-ankle vascular index, systolic blood pressure, pulse pressure in the left shoulder area, the delta of average blood pressure in the left ankle area.

Speeds of surface elastic wave propagation over the human chest along and across the ribs are found. Ten healthy male volunteers have participated in the experiment. Vibrations of a striker-vibrator and a light accelerometer in contact with the chest have been detected using a specially designed hardware and software complex. The transfer function phase for passage of elastic waves over the chest is calculated. Wave propagation speeds are found using the phase method (frequency dependence of the transfer function phase). Differences between the speeds along and across the ribs are found in the frequency ranges from 27 to 100 Hz and from 100 to 200 Hz with the maximal-to-minimal speed ratio of 1.8. It is shown that one of the causes for the differences between the speeds can be different local elasticity and viscosity of the chest tissues.

It is demonstrated that specimens of Polyommatus elena Stradomsky et Arzanov, 1999 form separate branches on cladograms of their mitochondrial COI and nuclear ITS2 sequences that are separate from specimens of P. icarus (Rottemburg, 1775) and P. icadius (Grum-Grshimailo, 1890). This may give evidence of species independence of Polyommatus elena

A lot of research is focused on finding better treatment options for cancer. Along with radical treatment, cancer immunotherapy has proved to be useful for a growing number of cancer patients. We report a case of stage IIIB melanoma in a 53-year woman who received adoptive immunotherapy with cytokine-induced killer (CIK) cells. For activation, mononuclear cells were collected from the patient’s peripheral blood and cultivated in X-vivo20 medium containing IL-2 (250 U/ml) and IL-15 (50 ng/ml) for 10-14 days. From January 2015 to May 2016, a total of 39 CIK cell infusions were administered intradermally to 2-4 points in the paravertebral area, every 1–2 weeks. Flow cytometric analysis of peripheral blood lymphocytes in 3 months after starting CIK cell immunotherapy showed a decrease in the number of NK-cells from 18 % to 12 % and CD314 + NK-cells from 16% to 6%. The levels of CD38+, CD38+Т, HLA-DR+ and HLA-DR+Т lymphocytes increased from 53 %, 24 %, 21 %, 9 % and 19 % to 66 %, 51 %, 28 %, 20 % and 29 %, respectively. There was evidence of reactive changes in lymph nodes and stable disease. Metastases on the left shoulder tended to decrease, and they completely disappeared 9 months after tarting adoptive immunotherapy. Partial regression of metastasis on the right shoulder was observed 11 month after staring adoptive immunotherapy. Adoptive immunotherapy demonstrated the increased disease-free survival for the patient with melanoma. In conclusion, CIK immunotherapy may be an effective treatment method for metastatic melanoma.

The degree of genetic diversity of the steppe field mouse was estimated on the basis of the mtDNA control region variability data. Polymorphism of this mtDNA marker in S. witherbyi was more pronounced than previously assumed. The steppe field mouse population from the northern shore of Lake Manych-Gudilo includes several mitochondrial lines, which may be due to the existence of several migration flows to this area from Southwest Asia.

Analysis of the control region of mitochondrial DNA (mtDNA) or D-loop of 96 house mice (Mus musculus) from Russia, Moldova, Armenia, Azerbaijan, Kazakhstan, and Turkmenistan has been used to reconstruct the phylogenetic relationships and phylogeographic patterns of intraspecific forms. New data on the phylogenetic structure of the house mouse are presented. Three phylogroups can be reliably distinguished in the eastern part of the M. musculus species range, the first one mainly comprising the haplotypes of mice from Transcaucasia (Armenia); the second one, the haplotypes of mice from Kazakhstan; and the third one, the haplotypes of mice from Siberia and some other regions. The morphological subspecies M. m. wagneri and M. m. gansuensis have proved to be genetically heterogeneous and did not form discrete phylogroups in the phylogenetic tree.

The superposition-additive approach developed and tested previously on monofunctional nonionic amphiphiles is updated and used for the calculation of the thermodynamic clusterization parameters for amphiphiles with two functional groups. In the framework of this approach the thermodynamic parameters of formation and clusterization for three classes of bifunctional amphiphiles were calculated using corresponding data for monofunctional amphiphiles. In the example of 2-hydroxycarboxylic acids, α-amino acids, and alkyl amides it was shown that the regarded approach adequately reproduces the parameter values of bifunctional amphiphiles without the direct use of quantum chemical calculations. It exploits rather only the calculated or experimental data existing for corresponding monofunctional amphiphiles. The systematic errors for the description of the thermodynamic parameters of formation and clusterization for bifunctional amphiphiles can be attributed to the incomplete reproduction of the values for the in...

The composition of ethanol extract of wheat straw obtained under subcritical and supercritical conditions has been studied. It was found out that treatment with increased temperature, pressure and prolonged time of extraction leads to increased yield of ethanol soluble products, because of destruction of pentosan, lignin and, partially, cellulose. Delignification and hydrolysis product condensation processes prevailed under treatment with temperatures higher than 200°C.

A simple method for estimation of the 2D spontaneous clusterization temperature of substituted alkanes at the air/water interface versus alkyl chain length is proposed using the quantum chemical semiempirical PM3 method. The method is approved by long-chain amines, alcohols, thioalcohols, saturated and unsaturated carboxylic acids, α-amino acids and amides of carboxylic acids. The method is based on the experimental fact that short chain amphiphilic molecules cannot form condensed 2D monolayers whereas above a specific alkyl chain length condensed monolayer phases can be observed under the same conditions. That is, elongation of the alkyl chain of amphiphilic molecules causes the increase of intermolecular interaction energy between them what stimulates their close packing and structuring. This leads to linear or stepwise dependencies of enthalpy and entropy of cluster formation on the alkyl chain length. It is possible to obtain an equation for the estimation of the temperature of the spontaneous clusterization threshold of the considered substituted alkane types by setting Gibbs’ energy equal to zero and by knowing the regression expressions for determination of enthalpy and entropy of cluster formation calculated under the condition of 298 K using coefficients which determine the contribution of the hydrophilic head group interactions of molecules and CH⋯HC-interactions between the alkyl chains. It is shown that the temperature dependence of the spontaneous clusterization threshold on the alkyl chain length of the amphiphile is fractionally linear with a relative error of 3–8%. The effect of the alkyl chain elongation of substituted alkanes by two methylene units corresponds to subphase temperature reduction (Δ Т ) by 10–20 K in good agreement with the available experimental data. The difference between Δ Т values for considered types of amphiphilic compounds becomes less significant with the lengthening of the alkyl chain. This indicates the basic contribution of intermolecular CH⋯HC-interactions between the alkyl chains to the process of the 2D clusterization.

The quantum-chemical semiempiric PM3 method is used to calculate the thermodynamic parameters of clusterization for the racemic α-amino acids C(n)H(2n+1)CHNH(2)COOH with n=5-15 at 278 and 298 K. Possible relative orientations of the monomers in the heterochiral clusters are considered. It is shown that, for the racemic mixtures of α-amino acids, the formation of heterochiral 2D films is most energetically preferable with the alternating (rather than "checkered") packing of the enantiomers with opposite specific rotation. The two enantiomeric forms of α-amino acids in the heterochiral 2D clusters are tilted with respect to the normal to the q direction at angles of φ(1)=20° and φ(2) = 33°, whereas the single enantiomeric forms are oriented at an angle of δ=9° with respect to the normal to the p direction. It is shown that the heterochiral 2D film based on the α-amino acid structures oriented at the angle φ(2)=33° with respect to the normal to the q direction possesses a rectangular unit cell with the geometric parameters a = 4.62 Å and b = 10.70 Å and the tilt angle of the alkyl chain of the molecule with respect to the interface t(2)=35°, which is in good agreement with the X-ray structural data a=4.80 Å, b=9.67 Å, and t(2)=37°. The parameters of the lattice structure of monolayers formed by amphiphilic amino acids are shown to be determined by the "a" type of the intermolecular H-H interactions, whereas the tilt angle of the molecules with respect to the interface depends on the volume and the structure of the functional groups involved in the hydrophilic part of the molecule. Spontaneous clusterization of the racemic form of α-amino acids at the air/water interface at 278 K takes place if the alkyl chain length is equal or higher than 12-13 carbon atoms, whereas for 298 K this clusterization threshold corresponds to 14 carbon atoms in the hydrocarbon chain. These values agree with the experimental data.

The semiempirical quantum-chemical PM3 method is used to calculate the thermodynamic parameters of clusterization of the S-form of alpha-amino acids with the general composition C(n)H(2n+1)CHNH(2)COOH (n = 5-15) at 278 and 298 K. It is shown that six stable conformations of monomers exist, for which the thermodynamic parameters (enthalpy and Gibbs' energy) of the formation and absolute entropy are calculated. The correlation dependencies of the calculated parameters on the alkyl chain length are found to be linear. The structures of the monomers are used to build larger clusters (dimers, tetramers, hexamers). For all small clusters (comprised of two to six molecules), the thermodynamic parameters of formation and clusterization are calculated. It is shown that for tetramers and hexamers the enthalpy, entropy, and Gibbs' energy of clusterization are linearly dependent on the alkyl chain length, whereas for the dimers these dependencies are stepwise. The thermodynamic characteristics of clusterization of associates tilted by angles of 9 and 30 degrees with respect to the normal to the interface are calculated. It is shown that the 30 degrees angle orientation is more energetically advantageous for this class of compounds. The geometric parameters of the unit cell characteristic for the infinite 2D film which corresponds to the most advantageous conformation of the monomer were calculated using the PM3 parametrization to be a = 4.57-4.71 A and b = 5.67-5.75 A, with the angle between the axes theta = 100-103 degrees . These values agree well with the available experimental data. Spontaneous clusterization of alpha-amino acids at the air/water interface at 278 K takes place if the alkyl chain length exceeds 11-12 carbon atoms, whereas for 298 K this clusterization threshold corresponds to 13-14 carbon atoms in the alkyl chain, also in agreement with the experimental data.

The structural parameters of fatty acid (with formula CnH2n+1COOH, n = 7–16) monolayers at the air/water interface were modeled within quantum-chemical semiempirical program complex Mopac 2012 (PM3 method). On the basis of quantum-chemical calculations it was shown that molecules in the highly ordered monolayer can be oriented at the angle ∼16° (tilted monolayer), or at the angle ∼0° to the normal to the air/water interface (untilted monolayer). The structural parameters of both tilted and untilted monolayers correspond well to the experimental data. The parameters of the unit cell of the modelled tilted monolayer are: a = 8.0–8.2 A and b = 4.2–4.5 A (with the corresponding experimental data 8.4–8.7 A and 4.9–5.0 A). For the modelled untilted monolayer these parameters are: a = 7.7–8.0 A; b = 4.6 A (with the corresponding experimental data 8.4 A and 4.8–4.9 A). Enthalpy, entropy and Gibbs' energy of clusterization were calculated for both structures. The correlation dependencies of the calculated parameters on the number of pair intermolecular CH⋯HC interactions in the clusters and the pair interactions between functional groups were obtained. It was shown that the spontaneous clusterization of the fatty carboxylic acids at the air/water interface under standard conditions is energetically preferable for molecules which have 13 or more carbon atoms in the alkyl chain and this result also agrees with the corresponding experimental parameters.

In the present study it is shown that parameters used in the framework of the model for the assessment of the threshold temperature of spontaneous clusterization of nonionic amphiphiles at the air/water interface (T(Cl)) are independent of the amphiphile type used in the developed schemes. The temperature dependence of the clusterization Gibbs' energies of alkyl amides, α-amino acids and 2-hydroxycarboxylic acids obtained in the framework of several schemes is listed. The exploited schemes differ from each other by the degree of their theoretical validity. The values of the clusterization threshold temperature for substituted alkanes can be described by a fractionally linear function versus the number of CH···HC interactions in the framework of the simplest scheme taking into account the found corrections and agree well with available experimental data.

The superposition-additive approach developed previously was shown to be applicable for the calculations of the thermodynamic parameters of formation and atomization of conjugate systems, their dipole polarizability, molecular diamagnetic susceptibility, π-electronic ring currents, etc. In the present work, the applicability of this approach for the calculation of the thermodynamic parameters of formation and clusterization at the water/air interface of alkanes, fatty alcohols, thioalcohols, amines, nitriles, fatty acids (C(n)H(2n+1)X, X is the functional group) and cis-unsaturated carboxylic acids (C(n)H(2n-1)COOH) is studied. Using the proposed approach the thermodynamic quantities determined agree well with the available data, either calculated using the semiempirical (PM3) quantum chemical method, or obtained in experiments. In particular, for enthalpy and Gibbs' energy of the formation of substituted alkane monomers from the elementary substances, and their absolute entropy, the standard deviations of the values calculated according to the superposition-additive scheme with the mutual superimposition domain C(n-2)H(2n-4) (n is the number of carbon atoms in the alkyl chain) from the results of PM3 calculations for alkanes, alcohols, thioalcohols, amines, fatty acids, nitriles and cis-unsaturated carboxylic acids are respectively: 0.05, 0.004, 2.87, 0.02, 0.01, 0.77, and 0.01 kJ/mol for enthalpy; 2.32, 5.26, 4.49, 0.53, 1.22, 1.02, 5.30 J/(molK) for absolute entropy; 0.69, 1.56, 3.82, 0.15, 0.37, 0.69, 1.58 kJ/mol for Gibbs' energy, whereas the deviations from the experimental data are: 0.52, 5.75, 1.40, 1.00, 4.86 kJ/mol; 0.52, 0.63, 1.40, 6.11, 2.21 J/(molK); 2.52, 5.76, 1.58, 1.78, 4.86 kJ/mol, respectively (for nitriles and cis-unsaturated carboxylic acids experimental data are not available). The proposed approach provides also quite accurate estimates of enthalpy, entropy and Gibbs' energy of boiling and melting, critical temperatures and standard heat capacities for several classes of substituted alkanes. For the calculation of thermodynamic functions of clusterization of dimers, trimers and tetramers of fatty alcohols, thioalcohols, amines, carboxylic acids and cis-unsaturated carboxylic acids two superposition-additive schemes are proposed which ensure the correct superimposition of the molecular graphs, including intermolecular hydrogen-hydrogen interactions in the clusters. The calculations involve the thermodynamic parameters of clusterization obtained earlier by the PM3 method. It is shown that the proposed approach reproduces quite accurately the values calculated earlier and is applicable for the prediction of the thermodynamic parameters of the formation of surfactant monolayers.

The applicability of the superposition-additive approach for the calculation of the thermodynamic parameters of formation and atomization of conjugate systems, their dipole electric polarisabilities, molecular diamagnetic susceptibilities, π-electron circular currents, as well as for the estimation of the thermodynamic parameters of substituted alkanes, was demonstrated earlier. Now the applicability of the superposition-additive approach for the description of clusterization of fatty alcohols, thioalcohols, amines, carboxylic acids at the air/water interface is studied. Two superposition-additive schemes are used that ensure the maximum superimposition of the graphs of the considered molecular structures including the intermolecular CH–HC interactions within the clusters. The thermodynamic parameters of clusterization are calculated for dimers, trimers and tetramers. The calculations are based on the values of enthalpy, entropy and Gibbs' energy of clusterization calculated earlier using the semiempirical quantum chemical PM3 method. It is shown that the proposed approach is capable of the reproduction with sufficiently enough accuracy of the values calculated previously.

Opsonins found on the surface of microbial cells in vivo and ex vivo are characterized. The possibility of their visualization by immune electron and fluorescent microscopy has been demonstrated. Opsonins are shown to play a role in immune-mediated adhesion of bacteria to phagocytes and erythrocytes and formation of virus-bacterium associations. Staphylococci, Streptococci, and Propionibacteria appear to actively adsorb blood proteins on their cell surface giving rise to well-apparent capsular structures tentatively called immunoglobulin coatings. Pathogen (microorganism)-associated molecular patterns of gram-positive and gram-negative bacteria show different degree of interaction with soluble proteins that in turn promote their adhesion to blood corpuscles. The role of erythrocytes in transportation and elimination of immune complexes bound to their membrane receptors is discussed.

In the framework of the quantum chemical semiempirical PM3 method, the thermodynamic and structural parameters of formation and clusterization were calculated for 2-hydroxycarboxylic acids with the general formula CnH2n+1CHOHCOOH (n = 5–15). Dimers and tetramers were formed on the basis of optimized monomer structures. It was shown that the alkyl chains in the considered associates orientate themselves with the following values of the tilt angles with respect to the p- and q-directions of the interface: δ = 7.2–21.2° and φ = 9.8–21.1° depending on the monomer structure of the cluster. Comparing the Gibbs energy values of clusterization for small aggregates, a possible scheme of 2D clusterization is proposed based on the formation of linear aggregates constructed by dimers with ‘parallel’ orientation of the functional groups for 2-hydroxycarboxylic acid monomers with n ≤ 16 carbon atoms in the alkyl chain. The following parameters of the unit cell for the most energetically preferred structure of 2D film 3 were found: a = 4.85 A, b = 5.41 A, and the angle between them θ = 95°. The molecular tilt angle of 2-hydroxycarboxylic acids with respect to the air/water interface was calculated to be t = 21.7°. The spontaneous clusterization threshold is 14 carbon atoms in the 2-hydroxycarboxylic acid chain at the air/water interface for a monolayer built on the basis of monomer 3 in good agreement with the existing experimental data.

In the framework of the quantum chemical semiempirical PM3 method thermodynamic and structural parameters of the formation and clusterization of aliphatic alcohols C(n)H(2n+1)OH (n(OH) = 8-16) at 298 K at the water/alkane vapor C(n)H(2n+2), (n(CH(3)) = 6-16) interface were calculated. The dependencies of enthalpy, entropy and Gibbs' energy of clusterization per one monomer molecule of 2D films on the alkyl chain length of corresponding alcohols and alkanes, the molar fraction of alkanes in the monolayers and the immersion degree of alcohol molecules into the water phase were shown to be linear or stepwise. The threshold of spontaneous clusterization of aliphatic alcohols at the water/alkane vapor interface was 10-11 carbon atoms at 298 K which is in line with experimental data at the air/water interface. It is shown that the presence of alkane vapor does not influence the process of alcohol monolayer formation. The structure of these monolayers is analogous to those obtained at the air/water interface in agreement with experimental data. The inclusion of alkane molecules into the amphiphilic monolayer at the water/alkane vapor interface is possible for amphiphiles with the spontaneous clusterization threshold at the air/water interface (n(s)(0)) of at least 16 methylene units in the alkyl chain, and it does not depend on the molar fraction of alkanes in the corresponding monolayer. The inclusion of alkanes from the vapor phase into the amphiphilic monolayer also requires that the difference between the alkyl chain lengths of alcohols and alkanes is not larger than n(s)(0) - 15 and n(s)(0) - 14 for the 2D film 1 and 2D film 2, respectively.