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The K98 capsular polysaccharide (CPS) from the Acinetobacter baumannii clinical isolate, REV-1184, was studied by sugar analysis and Smith degradation along with one- and two-dimensional

Two acylated forms of the higher sugar, 5,7-diamino-3,5,7,9-tetradeoxy-l-glycero-l-manno-non-2-ulosonic acid called pseudaminic acid, Pse5Ac7Ac and Pse5Ac7RHb where R indicates (R)-3-hydroxybutanoyl, have been found to occur in many capsular polysaccharide (CPS) types produced by isolates of an important human pathogen, Acinetobacter baumannii. The presence of either a psaABCEDF or psaABCGHF gene module at the K locus (KL) for CPS biosynthesis determines the type of the variant produced. Here, an A. baumannii clinical isolate 52-249, recovered in 2015 in Moscow, Russia, was found to include a novel psaABCIJF gene module in the KL218 sequence at the K locus. The CPS from 52-249 was extracted and studied by sugar analysis and partial acid hydrolysis along with one- and two-dimensional

Aim: to study fatty acid levels in erythrocyte membranes (RBC) and blood serum (BS) in patients with inflammatory bowel diseases (IBDs) to develop differential diagnostic models including fatty acids as biomarkers to distinguish between nosological entities of IBDs (ulcerative colitis — UC, Crohn's disease — CD, unclassified colitis — UCC).Materials and methods. We examined 110 patients (mean age 37,7 ± 12,1 years) with IBDs and 53 healthy patients in control group (43,3 ± 11,7 years). The IBDs group included 50 patients with UC, 41 patients with CD, 19 patients with UCC. An exacerbation of the disease was revealed in 42 patients (84 %) with UC, 34 patients with CD (82.9 %) and 11 people with UCC (57.9 %). The study of fatty acids (FA) composition of RBC membranes and BS was carried out using GC/MS system based on three Agilent 7000B quadrupoles (USA).Results. The most significant for distinguishing active UC from CD exacerbation were serum levels of elaidin (p = 0.0006); docosatetraenoic (n-6) (p = 0.004); docodienic (n-6) (p = 0.009); omega-3/omega-6 ratio (p = 0.02); docosapentaenoic (n-3) (p = 0.03); the sum of eicosapentaenoic and docosahexaenoic (p = 0.03), as well as the content of RBC lauric FA (p = 0.04) (AUC — 0.89, sensitivity — 0.91, specificity — 0.89, diagnostic accuracy — 0.91). To distinguish active UC from the same of UCC, the following serum FA were found to be significant: alpha-linolenic; saturated (pentadecanoic, palmitic, stearic, arachidic); monounsaturated (palmitoleic, oleic); omega-6 (hexadecadienic, arachidonic) (p = 0.00000011—0.03300000) (AUC — 0.995, sensitivity — 0.98, specificity — 0.96, diagnostic accuracy — 0.97). The most significant in distinguishing patients with active CD from UCC exacerbation were levels of the following FA: alpha-linolenic; palmitoleic; oleic; the amount of saturated fatty acids (SFA); total unsaturated fatty acids (UFA); stearic; monounsaturated fatty acids (MUFA) amount; SFA/UFA; SFA/PUFA (polyunsaturated fatty acids); linoleic; total PUFA n6; lauric; arachidic acid (p = 0.0000000017–0.030000000) (AUC — 0.914, sensitivity — 0.90, specificity — 0.87, diagnostic accuracy — 0.91).Conclusion. The study of FA levels in groups with different nosological forms of IBDs using complex statistical analysis, including machine learning methods, made it possible to create diagnostic models that differentiate CD, UC and UCC in the acute stage with high accuracy. The proposed approach is promising for the purposes of differential diagnosis of nosological forms of IBDs.

The detailed experimental studies of the autothermal and steam reforming of model mixtures simulating the composition of commercial diesel fuel were carried out over Rh/Ce0.75Zr0.25O2-δ-ƞ-Al2O3/FeCrAl wire mesh honeycomb catalytic modules. The components of the diesel surrogates were n-hexadecane, o-xylene, and naphthalene as model compounds of aliphatics, mono-aromatics and diaromatics, respectively. It was shown that low reaction rate of diaromatics steam reforming facilitated increasing concentration of C1–C5 hydrocarbon by-products (primarily ethylene) in the gas phase, as well as formation of polyaromatic compounds by concurrent condensation reaction. These undesirable processes were responsible for increasing catalyst coking. Monoaromatic constituents hadn't any significant effect on the progress of undesirable side-reactions during autothermal and steam reforming of diesel surrogates.

The textbook presents the conditions of problems and solutions of examples in the main sections of mathematical statistics using Microsoft Excel and the R language. Meets the requirements of the federal state educational standards of higher education of the latest generation. For students of higher educational institutions studying in economic specialties.

The textbook outlines the basic concepts and methods of probability theory, their implementation by means of the R language. There are many examples and problems with detailed solutions. Meets the requirements of the federal state educational standards of higher education of the latest generation. For students studying in the fields of "Economics", "Business Informatics", graduate students, researchers and teachers.

Burnt deposits are an important source of information on ancient lifestyles, providing the possibility of reconstructing the size, intensity of use, and functions of fi replaces at prehistoric settlements, and to assess fuel sources. We outline the results of a multidisciplinary study of fi replaces and their contexts at Surungur—a stratifi ed site in the Fergana Valley, in southern Kyrgyzstan. Sixteen samples from ash lenses and intermediate deposits were studied by rock-magnetism, gas chromatography mass spectrometry (GC-MS), and X-ray fl uorescence (XRF). The rock-magnetic analysis suggests that the origin of all samples from ash lenses was anthropogenic. Types of fuel were reconstructed. At the initial stage (Early Holocene), the encompassing deposits likely resulted from short-term occupation, and fuel consisted of wood and grass/ dung. In the Middle Holocene, occupation became more long-term, as evidenced by maximal heating temperatures and high concentration of fi replaces. During the Late Holocene, habitation intensity on the platform under the stone ledge remained the same, but heating was less intense. Wood and grass/dung were used as fuel at all stages, suggesting that wood was available in the region throughout the Holocene.

Sustainable development of Afghanistan is prevented by many factors, both purely anthropogenic genesis, and natural. In this study, author tries to make an initial assessment of the possibility of indicating geoecological problems in Afghanistan by indicators of the sustainable development goals based on landscape analysis. This will allow to identify priorities in the practical application of these indicators, and to conduct field assessments with maximum efficiency. Author makes a point assessment of the priorities of the indication of the geoecological problems of different landscape units of Afghanistan, and the related assessment of tension of the geoecological situation.

The subject of the research is the process of modeling the functioning of a traffic light, providing adaptive control of vehicles at the intersectionsof the city transport network. In the process of functioning of urban transport networks, such phenomena as traffic jams occur, which lead tosignificant economic losses, environmental degradation, frustration of road users and other types of negative impacts. Traffic jams often occur at thenodes of the urban transport network, which are intersections - the places of intersection, abutment or branching of roads of the urban network of thesame level. One of the causes of congestion is the ineffective management of traffic flows at intersections, which is provided by such an element of theintersection as a traffic light. Within the framework of the existing transport network, traffic lights that implement adaptive control with the help ofappropriate local controllers, and more complex system controllers created on their basis, ensuring that the situation in the external environment istaken into account, which is represented by several interconnected intersections, is currently one of the most important directions for solving theproblem of traffic jams. The traffic light flow control function is implemented using a microprocessor controller, which, according to a given algorithm, switches the traffic light colors corresponding to the phases of allowing and prohibiting the movement of the vehicle in the directions of theintersection roads.The article proposes a mathematical model for building an algorithm for the functioning of a microprocessor traffic light controller, whichprovides a prompt and adequate display of situations at intersections. The main features of the model include responsiveness to changes in situations atan intersection by changing the duration of the permissive phase of movement in each cycle of traffic light operation in proportion to the length of thequeue of vehicles in the corresponding direction of travel; adequate display of the external environment by several expressions of Poisson’s law,differing in different values of the parameter, each of which corresponds to a certain daily interval of traffic light functioning; the dynamics of changesin the traffic situation due to a decrease in the number of vehicles in the queue due to the passage of the intersection by vehicles during the green phaseof the traffic light is determined on the basis of expressions that determine the movement of bodies with uniformly accelerated and uniform movement,as well as on the basis of the differential equation of the dynamics of movement of vehicles in one row taking into account the delay caused by thereaction of drivers.

Whole genome sequence from Acinetobacter baumannii isolate Ab-46-1632 reveals a novel KL144 capsular polysaccharide (CPS) biosynthesis gene cluster, which carries genes for d -glucuronic acid ( D -GlcA) and l -rhamnose ( l -Rha) synthesis. The CPS was extracted from Ab-46-1632 and studied by 1H and 13C NMR spectroscopy, including a two-dimensional 1H,13C HMBC experiment and Smith degradation. The CPS was found to have a hexasaccharide repeat unit composed of four l -Rhap residues and one residue each of d -GlcpA and N-acetyl- d -glucosamine ( D -GlcpNAc) consistent with sugar synthesis genes present in KL144. The K144 CPS structure was established and found to be related to those of A. baumannii K55, K74, K85, and K86. A comparison of the corresponding gene clusters to KL144 revealed a number of shared glycosyltransferase genes correlating to shared glycosidic linkages in the structures. One from the enzymes, encoded by only KL144 and KL86, is proposed to be a novel multifunctional rhamnosyltransfaerase likely responsible for synthesis of a shared α- l -Rhap-(1 → 2)-α-L-Rhap-(1 → 3)-L-Rhap trisaccharide fragment in the K144 and K86 structures.

Lytic bacteriophage have potential for the treatment of otherwise untreatable extensively antibiotic-resistant bacteria. For Acinetobacter baumannii , most phage exhibit specificity for the type of capsular polysaccharide (CPS) produced on the cell surface.

Objective. People experience lucid dreaming (LD) with different emotions and perceptions that can have psychophysiological consequences upon waking. To study the placebo without a deception effect, we tested how psychoactive drug intake during LDs affects perceptions in dreams and after waking.Method. Through two online experiments, we instructed volunteers to consume alcohol (N = 104) and psychoactive substances (N = 86) while in an LD and then wake up to assess the results. Results. For both groups, 58% of the volunteers felt an effect of psychoactive drugs while in an LD, and 21% were able to transfer these effects into wakefulness, at least partially. Psychoactive substances were more likely to maintain their effect upon awakening than alcohol (p = .002).Discussion. The results show that the sensory and emotional neurons responsible for perceptions of alcohol and drug intake can fire independently from physiology. The transfer of these effects to wakefulness could be possible due to hypnopompic hallucination. Probably, the type of alcohol or drug consumed, as well as the intake method, were important factors . The outcomes of our study contribute to the overall understanding of the psychophysiological correlations between LD and wakefulness and its possible applications in health treatments.

We investigate artificial intelligence and machine learning methods for optimizing the adversarial behavior of agents in cybersecurity simulations. Our cybersecurity simulations integrate the modeling of agents launching Advanced Persistent Threats (APTs) with the modeling of agents using detection and mitigation mechanisms against APTs. This simulates the phenomenon of how attacks and defenses coevolve. The simulations and machine learning are used to search for optimal agent behaviors. The central question is: under what circumstances, is one training method more advantageous than another? We adapt and compare a variety of deep reinforcement learning (DRL), evolutionary strategies (ES) and Monte Carlo Tree Search methods within Connect 4, a baseline game environment, and on both a simulation supporting a simple APT threat model, SNAPT, as well as CyberBattleSim, an open-source cybersecurity simulation. Our results show that when attackers are trained by DRL and ES algorithms, as well as when they are trained with both algorithms being used in alternation, they are able to effectively choose complex exploits that thwart a defense. The algorithm that combines DRL and ES achieves the best comparative performance when attackers and defenders are simultaneously trained, rather than when each is trained against its non-learning counterpart.

Herein, we report the direct selective C-H lactonization of fatty acids (C5-C16), catalyzed by manganese(II) complexes bearing bis-amino-bis-pyridine ligands. The catalyst system uses the environmentally benign hydrogen peroxide as oxidant and exhibits high efficiency (100-200 TON), providing under optimized conditions γ-lactones in 60-90% yields. Remarkably, by changing the reaction conditions, the oxidation of hexanoic acid can be diverted toward formation of δ-caprolactone in up to 67% yield. Furthermore, the possibility of obtaining (ω-1)-hydroxy derivatives from linear C7-C10 acids in up to 48% yields has been demonstrated.

Hydrotreatment of birch wood pyrolysis liquid (PL) was carried out at 350 °C and 6.0 MPa initial hydrogen pressure (RT) for 4 h in a batch autoclave using promising high-loading Ni-based catalysts stabilized by SiO2. Different additives (Cu, Mo, Cr, P) were used to modify the catalysts. The products in liquid organic (OPh) and aqueous phases (AqPh) after PL hydrotreatment were characterized by different methods, such as gas chromatography-mass spectrometry (GC–MS), Fourier-transform infrared (FTIR) spectroscopy, gel permeation chromatography (GPC), etc. Herein, the performance of the catalysts was evaluated by considering the yield and chemical composition of the products (gaseous phase, OPhs, AqPhs, and coke). For the MoCr-containing system, a higher yield of the aqueous phase with low O/C ratio was observed that could be explained by more effective hydrodeoxygenation of water-soluble compounds due to Ni-Mo-Cr solid solutions and coordinatively unsaturated Cry+ and Mox+ sites. P-modified NiCuMoP-SiO2 and NiCrP-SiO2 catalysts reveal more intense CO2 formation very likely due to decarboxylation over Ni3P particles, thus leading to the decrease in the oxygen content in organic phase to 14 wt.%. Fresh reduced catalysts were examined by CO chemisorption, X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM) to provide insights into the structure and morphology. High resistance to coke formation was evidenced according to CHNS analysis of spent samples, besides, the stability of catalysts was additionally assessed by X-ray diffraction.

In this study, new results of comparative research on autothermal reforming(ATR) of biofuels (hydrodeoxygenated biodiesel and long- stored biodiesel) over composite RhSC catalysts (0.24 wt.% Rh supported on structured Ce0.75Zr0.25O2-δ-ƞ-Al2O3/FeCrAl carrier) were obtained. The impact of fuel chemical composition on the catalyst performance was discussed. Hydrodeoxygenated biodiesel mainly consisted of heptadecane, other normal alkanes and small amounts of alkenes together with a portion of unreacted fatty acid ethers. RhSC exhibited syngas productivity of about 2.5 m3Lcat−1 h−1 (STP) at complete conversion of hydrodeoxygenated biodiesel without considerable by-products formation, at molar ratios O2/C = 0.54, H2O/C = 3, T =750 °C and GHSV =5000 h−1. The catalyst exhibited stable operation and no coke formation for at least 90 h on stream. Biodiesel after nine years storage, which was used in this study, contained methyl esters of saturated and unsaturated fatty acids and a large proportion of polymeric compounds. It was successfully demonstrated that even this aged biodiesel can be converted to synthesis gas over the developed Rh/Ce0.75Zr0.25O2-δ-ƞ-Al2O3/FeCrAl structured catalyst. Further optimization of the catalyst and reaction conditions (higher temperature, lower GHSV, catalyst doping by promoters) is required for reaching efficient reforming of the aged biodiesel. Nevertheless, it was demonstrated that biodiesel and hydrodeoxygenated biodiesel, which combine high energy density and renewability, were very attractive biofuels for fuel cell-based power unit applications.

The Rh/Ce0·75Zr0·25O2–δ-ƞ-Al2O3/FeCrAl structured catalytic blocks of length 10, 20, and 60 mm were prepared and tested in the reactions of steam and autothermal reforming of n-hexadecane. It was found in a series of experiments on hexadecane steam reforming with the catalyst heating solely through the reactor wall that the complete conversion of hexadecane at a furnace temperature below 750 °C was not achieved even at GHSV = 10,000 h−1. Under these conditions, the formation of carbon on the catalyst surface was observed. At the reactor wall temperature of 800 °C, the complete conversion of hexadecane was achieved even in the 10 mm long catalytic block (GHSV = 60,000 h−1), accompanied by the formation of various intermediate light hydrocarbons. To achieve complete conversion of these intermediate compounds (mainly 1-alkenes), it is necessary to carry out the steam reforming reaction at GHSV = 10,000 h−1. At hexadecane autothermal reforming, heat is supplied to the reaction zone by exothermic oxidation reaction, which makes this process more efficient. In experiments with the use of additional external heat supply through the reactor wall, complete conversion of hexadecane occurred at GHSV = 120,000 h−1. To convert all by-products (mainly 1-alkenes) and achieve a nearly thermodynamic equilibrium distribution of the main reaction products (H2, CO, CO2), the reaction should be carried out at GHSV = 20,000 h−1. Without external heat supply, hexadecane conversion decreased, while the content of light hydrocarbons in the reaction products increased. An increase in the inlet amount of oxygen helps to compensate the heat losses in the reactor and to increase the efficiency of hexadecane autothermal reforming. The performed experiments allow better understanding of the processes which occur during the steam and autothermal reforming of diesel.

Probe methods can not be considered a technology suitable for large-scale production of nanostructures due to low productivity and the difficulty of constructing three-dimensional structures. It is important, however, that they demonstrate the possibility of constructing complex nanostructures in the laboratory for research purposes. Experiments of this kind make it possible to study the physics of low-dimensional structures and to investigate the possibilities of their practical use in electronic devices. In this paper, we have investigated the technology of creating gold low-dimensional conductors on a dielectric substrate by methods of probe lithography. A literature analysis was conducted, during which was proposed a method for creating conductors based on the method of electric mass transfer. The contact pad of the 142EN1B microcircuit was used as a sample. To form a substrate with the required thickness of the gold film, the technology of chemical thinning (etching) of the surface of the finished sample was applied. A mixture of hydrochloric HCl and nitric acids HNO3 was chosen as a solution for etching gold. Within the framework of this work, the technique of preparing the substrate was developed, the parameters of STM lithography were investigated, and gold conductors were formed on the substrate. On the basis of the developed technology, nanoscale structures were obtained. Microscopic analysis showed that the minimum cross-section of the obtained gold conductors was 15…20 nm, the length was more than 50 nm.

An advanced fabrication technology of reaction-bonded SiC is developed, which includes the preparation of a C/SiC preform by repeated cycles of phenolic resin impregnation and pyrolysis, followed by infiltration with silicon melt. The use of different number of impregnation stages provides control of carbon content in the preform and the corresponding SiC content in final ceramics. The effect of the impregnation number on the preform characteristics and ceramics composition, thermal and mechanical properties are investigated comprehensively. With an increase of impregnation number up to four, SiC fraction in the ceramics enlarges to 93 vol%, thermal conductivity and Young’s modulus increase to 186 W/(m∙K) and 427 GPa respectively, which are superior to most reaction-bonded SiC. Flexural strength (225 MPa) and thermal expansion coefficient (2∙10−6 K-1) are not dependent on the impregnation number. The obtained results provide an opportunity to design and fabricate reaction-bonded SiC ceramics with a given set of properties.

Considering the increasing interest for Al alloys in the packaging industry, where component lightweighting allows higher process efficiency, as well as the increasing use of additively manufactured parts, which may not show a satisfactory tribological behaviour in the as-built condition, anodising by Electrochemical Oxidation (ECO) and Plasma Electrolytic Oxidation (PEO) was applied to as-built A357 (AlSi7Mg0.6) produced by Laser Powder Bed Fusion (LPBF). ECO allowed to compensate surface and surface-connected defects in LPBF A357 and produced a thicker, less-defective anodic oxide than PEO, providing higher wear resistance whilst maintaining a lower Coefficient of Friction (COF) in dry sliding tests against 100Cr6 steel. Polishing before ECO only resulted in negligible friction and wear improvements, even if it improved the compactness of the anodic oxide.