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Nickel‐based superalloys are unique materials with complex doping that demonstrate excellent resistance to mechanical and chemical degradation. Over a long period of use in industry, a variety of information has been accumulated about their possible chemical compounds and features corresponding to a certain composition. One of the main service properties of the alloy is the tensile strength (σ). For a more convenient comparison of the characteristics of the alloys with different chemical compositions, the temperature and holding time of the metal during testing are often combined into a complex Larson–Miller parameter (PLM). The availability of experimental or simulated data on the alloys' properties in the entire range of temperatures and exposures would significantly expand the possibilities of the alloy applications and would allow a more accurate evaluation and comparison of the alloys. In this work, we use a machine learning method for modeling the properties of the alloys according to their composition. A Bayesian regularized artificial neural network was engaged to simulate missing tensile strength values for 278 superalloys. Special data preprocessing and the use of an ensemble of networks during training reduced the model error. Comparison of the predicted and experimental data showed excellent convergence. The method made it possible to obtain enough data to approximate the relation σPLM with a sigmoid function. The slope coefficient is considered as a quantitative expression of the thermal stability of the superalloys. [ABSTRACT FROM AUTHOR]

As an economic development determinant, transport needs to be improved on an ongoing basis. This is due to complex dynamic processes taking place both within the state and internationally. Social and economic transformations and scientific progress of the 21st century in the national economic sectors challenge the national policy of any state. The readiness for macroeconomic turbulence and the level of adaptability depend, to a decisive extent, on the economic potential of the state, where transport is the connecting link between the production, research and technical, agricultural and social components. As a backbone industry, the transport complex is based on infrastructure. The development of transport infrastructure is fundamental and is considered a priority not only at the national level, but also within the framework of globalization processes. Thus, the importance of resolving the issues of transport infrastructure development is due to the rapid development of the national economy as a whole. In this regard, the article emphasizes the importance of the integrated innovative development of Russia’s transport complex infrastructure and reveals promising directions for its development in conditions of market constraints.

The strategy for the development of the supply chain should ensure a high level of fault tolerance of all links when exposed to adverse factors. The article analyzes the impact on the stability of the supply chain of two types of influences: failure and disruption. The low stability of the supply chain appears in the stoppage of work in case of any disruptions and failures. With moderate stability, disruptions do not give up a significant impact on the operation of the supply chain, and failures lead to an increase in operating costs to maintain the stability of work processes. With a high level of stability, failures can cause disruptions in the operations of individual links. In case of disruptions, response models are applied based on the control of process parameters, the subsequent analysis of the causes of disruptions and the development of measures to restore the normal operation of the links in the supply chain. Effective disruption response involves the use of proactive response models. For this, it is necessary to ensure flexibility and transparency of processes in all links of the supply chain based on digital services for material flow control and mining of big data.

Our recently reported AquaSolv Omni (AqSO) process shows great potential as a parameter‐controlled type of biorefinery, which allows tuning of structure and properties of the products towards their optimal use in high‐value applications. Herein, a comprehensive NMR (quantitative 13C, 31P, and 2D heteronuclear single‐quantum coherence) structural characterization of AqSO lignins is reported. The effect of the process severity (P‐factor) and liquid‐to‐solid ratio (L/S) on the structure of the extracted lignins has been investigated and discussed. Low severity (P‐factor in the range 400–600) and L/S=1 led to the isolation of less degraded lignin with a higher β‐O‐4 content up to 34/100 Ar. Harsher processing conditions (P‐factor=1000–2500) yielded more condensed lignins with a high degree of condensation up to 66 at P‐factor=2000. New types of lignin moieties, such as alkyl‐aryl and alkyl‐alkyl chemical bonds together with novel furan oxygenated structures have been identified and quantified for the first time. In addition, the formation of lignin carbohydrate complexes bonds has been hypothesized at low severity and L/S. Based on the obtained data we were able to formulate a possible outlook of the occurring reactions during the hydrothermal treatment. Overall, such detailed structural information bridges the gap from process engineering to sustainable product development. [ABSTRACT FROM AUTHOR]

Among numerous melt structure model representations, the most relevant for liquid heat-resistant nickel alloys description is the quasicrystalline model of a microinhomogeneous structure, in which it is assumed that multicomponent nickel melts consist of clusters and intercluster space. Clusters inherit the short-range order of the atomic structure from various phases of the initial solid metal crystalline structure. Heating the melt to a certain temperature and/or increasing a period of its isothermal holding at constant pressure led to a second-order phase liquid–liquid phase transition (LLT). As a result, atomic associations that are more balanced and uniformly distributed over the melt volume are formed. Structural changes in nickel superalloy melts are irreversible and have a significant effect on the formation of the structure and properties of a solid metal during crystallization. Structural LLT changes in multicomponent nickel melts are the basis for a scientific substantiation of the technological modes of smelting, which contributes to an improvement in the technological properties of melts, a reduction of metallurgical defects, a rational use of expensive elements and foundry waste, as well as a significant improvement in the quality of metal products. This work is devoted to the experimental determination of the LLT transition in superalloy melts by the noninvasive electromagnetic method. [ABSTRACT FROM AUTHOR]

Tone reproduction curves (TRCs) have long been the basis for color adjustment in printing systems. Moreover, new algorithms for their processing and calculation, including tone value increase (TVI)‐based ones, are being constantly proposed. However, due to the fact that TRCs are just one‐dimensional curves covering only one colorant, they are not able to produce an exact match of all colors. Color adjustment with the help of the TRC is unstable, that is, a slight change in one color channel has a dramatic effect on the color reproduction in output. The use of gradation trajectories (GT) as an analytical model within the CIE Lab color space describing the behavior of the entire color gamut of the reproduction device makes it possible to more accurately adjust the individual color channel. Describing GT using the parametric Bézier curves further simplifies this process. In this work, we use GT to fit the TRC/TVI with the parameters recommended by ISO 12647‐2:2013. [ABSTRACT FROM AUTHOR]

The accuracy and repeatability of the color reproduction in print is determined by the fine‐tuning of the tone reproduction curves of the basic printing colorants (most often this is CMYK). However, the diversity of manufacturers of printing equipment and dyes introduces an element of significant uncertainty about color uniformity. In addition, the traditional approach does not take into account the effect of hue change when applying the original dyes, as well as the nonlinearity of the hue rise in high‐ and low‐density areas. Determining the color of base colorants that produces the most uniform tone change is an important engineering challenge. Previously, there was no scientific basis for such calculations. We recently proposed an alternative color correction model based on gradation trajectories as an analogue of gradation curves in the CIE Lab space. We have also described the extension of the approach to double color overlay (gradation surfaces) and its analytical and discrete implications. The trajectories are the geodetic lines on gradation surfaces. In this paper, we propose using the gradation trajectories to determine "ideal" or "true" initial printing dyes for electrophotography. To simplify calculations, natural color discretization in digital printing is used. [ABSTRACT FROM AUTHOR]

Nickel alloys are widely used in the manufacture of gas turbine parts. The alloys show resistance to mechanical and chemical degradation under prolonged loads and high temperatures. The properties of an alloy are determined by its composition and are subject to careful modeling. A set of basic refractory elements makes a special contribution to the parameters of the alloy. One of the main mechanical properties of the alloys is the high‐temperature tensile strength. Determining the influence of certain elements on certain properties of an alloy is a complex scientific and engineering problem that affects the time and cost of developing new materials. Simulation is a great chance to cut costs. In this article, we predict high temperature strength based on the composition of refractory elements in alloys using a specially designed deep learning artificial neural network. We build the model based on prior knowledge of alloy composition, information on the role of alloying elements, type of crystallization, test temperature and time, and tensile strength. Successful simulation results show the applicability of this method in practice. [ABSTRACT FROM AUTHOR]

The current biorefineries are focused on the comprehensive fractionation of biomass components into separate lignin and carbohydrate fractions for the production of materials, platform chemicals and biofuel. However, it has become obvious that the combination of lignin and carbohydrates can have significant technical, environmental, and economic benefits as opposed to their separate use. Herein, we developed a green, simple, and flexible biorefinery concept for the integrated utilization of all major biomass components for high-value applications with the focus on functional lignin–carbohydrate hybrids (LCHs). The established process consisted of a modified hydrothermal treatment (HTT) of birch wood followed by solvent extraction of the resulting solids and is therefore named AquaSolv Omni (AqSO) biorefinery. The AqSO biorefinery produces three major streams: hydrolysate (hemicellulose-derived products), solvent-extracted lignin–carbohydrate complexes (LCCs) and cellulose-rich fibers. Specific process conditions were found to facilitate the production of LCCs of different types in high yields as a new valuable and industrially realistic process stream. The effect of the process severity and liquid to solid (L/S) ratio on the yields and compositions of the produced fractions as well as on the structure and properties of the extracted LCCs was investigated using state of the art NMR spectroscopy and molar mass distribution analysis among other methods. The high flexibility of the process allows for engineering of the resulting products in a wide range of chemical compositions, structures and physicochemical properties and therefore gives a good opportunity to optimize the products for specific high-value applications. The process can be easily combined with other biorefinery operations (e.g., enzymatic hydrolysis, pulping, bleaching) to be incorporated into existing value chains or create new ones and thus is suitable for different biorefinery scenarios. First examples of high-value applications of AqSO biorefinery LCHs are reported. LCC nanoparticles (LCCNPs) were produced for the first time directly from the solvent extract and their properties were investigated. LCCNPs could efficiently stabilize Pickering emulsions of tetrahydrofurfuryl methacrylate and allowed their free radical polymerization. In addition, AqSO LCHs showed promising results as wood adhesives. Overall, our results provide detailed information on the complex lignocellulosic fractions and bridge the gap from process engineering to sustainable product development. [ABSTRACT FROM AUTHOR]

Introduction: The objective of this study was to identify risk factors for deep sternal wound infection (DSWI) after off-pump coronary artery bypass (OPCAB) grafting surgery. Methods: A total of 8,442 patients undergoing OPCAB from April 1, 2009 to December 31, 2018 were retrospectively analyzed. A total of 956 were eventually enrolled on this study based on our exclusion criteria. All subjects were divided into two groups: group 1 (n=63) -- DSWI; group 2 (n=893) -- without DSWI. Patients were excluded if they had one of the following: acute coronary syndrome, conversion to OPCAB grafting surgery, redo procedure, concomitant cardiac surgery procedures. Results: The prevalence of body mass index (BMI) ≥40 kg/m² (7.9% vs. 1.9%, respectively; P=0.01), lower extremity atherosclerotic artery disease (23.8% vs. 7.2%, respectively; P=0.001) and use of bilateral internal thoracic artery (19.5% vs. 2.5%, respectively; P=0.008) was significantly higher in patients with DSWI. The incidence of morbidities, including reoperation for bleeding (26.4% vs. 2.1%, respectively; P<0.001), stroke (4.8% vs. 0.8%, respectively; P=0.02), acute renal failure (7.9% vs. 0.8%, respectively; P=0.001), delirium (7.9% vs. 1.7%, respectively; P=0.008) and blood transfusion (30.6% vs. 9.8%, respectively; P<0.001) was significantly higher in patients with DSWI. Conclusions: A BMI of >40 kg/m², lower extremity artery disease, use of bilateral internal thoracic artery (BITA) graft, postoperative stroke, sepsis, reoperation due to postoperative complications and blood product requirement significantly increased the risk of sternal infection after OPCAB. [ABSTRACT FROM AUTHOR]

The paper provides an overview of existing models of the liquid metals structure, as well as the structural changes in their melts as a result of thermal treatment. The most important, in our opinion, are various versions of the quasicrystal model. The model is leant on the assumption that the melt consists of clusters and disordered space. The clusters as atomic micro-groups inherit the short-range order of the atomic structure from the solid state. Increasing the temperature of the melt and/or the holding time under isobaric conditions leads to polymorphic transformations of the short-range order. As a result, a new structure with smaller radii of atomic micro-groups, a lower lattice parameter and coordination number, and a more uniform distribution of elements is formed. The structural changes of the melts are irreversible and have a significant effect on crystallization and the formation of the structure and properties of the solid metal. [ABSTRACT FROM AUTHOR]

Color measurement forms the basis of color management and color prediction theory and widely used in all aspects of color reproduction. Spectrophotometers are basic tools in color measurement; however, their photometric accuracy and precision, especially with a temporary resolution, have not been studied enough. In this work, we describe a specially developed experiment for the spectrophotometer's constancy assessment. We invite two common instruments to inspect X‐Rite ColorMunki and X‐Rite i1 Pro. Different precision tests basing on color difference and reflectance comparison are utilized. We obtain coincident results for both instruments. The measured parameters consistently change over time; however, the magnitude of these changes is small. The magnitude of the color difference obtained in the experiment for both devices does not exceed 0.45 (in relative dimensionless units dE). [ABSTRACT FROM AUTHOR]

Objective: To compare the in-hospital outcomes of a right-sided anterolateral minithoracotomy with those of median sternotomy in patients who received a mitral valve replacement (MVR) because of rheumatic mitral valve stenosis (RMS). Methods: This is a retrospective analysis of 128 patients (34% male) with RMS between 2011 and 2015. The median age was 53 years (45; 56). The mean ejection fraction was 58.4±6.3%. All the subjects were divided into two groups - Group 1 contained 78 patients who underwent MVR via minithoracotomy (MT-MVR), while Group 2 contained 50 patients who underwent MVR via median sternotomy (S-MVR). Results: In the MT-MVR group, a mechanical prosthesis was implanted in 72% of cases, while it was implanted in 90% of cases in the S-MVR group (P=0.01). The duration of myocardial ischemia was similar (MT-MVR, 77±24 min; S-MVR, 70±18 min) (P=0.09). However, the cardiopulmonary bypass time was lower in the S-MVR group than in the MT-MVR group (99±24 min and 119±34 min, respectively) (P≤0.001). There was no difference in the duration of mechanical ventilation, intensive care unit stay, and hospitalization period. Postoperative blood loss was lower in the MT-MVR group (P≤0.001) than in the S-MVR group. There are no statistically significant differences in postoperative complications (superficial wound infection, stroke, delirium, pericardial tamponade, pleural puncture, acute kidney insufficiency, and implantation of pacemaker). The overall in-hospital mortality was 3.9% (P=0.6) Conclusion: The minimally invasive approach for RMS is feasible and has an excellent cosmetic effect without increasing the risk of surgical complications. [ABSTRACT FROM AUTHOR]

In aortic valve disease cases, prosthetic valves have been used for valve replacement, however, these prostheses have inherent problems, and their quality in some countries is lower comparing to new-generation models, causing shorter durability. Aortic valve neocuspidization (AVNeo) has emerged as an option, which can be applied to a wide spectrum of these diseases. Despite the promising results, this procedure is not widely spread among cardiac surgeons yet. We developed a surgical technique combining Bentall and Ozaki procedures to treat patients with concomitant ascending aorta replacement and AVNeo and we describe it in this paper. [ABSTRACT FROM AUTHOR]

In a neutral sulfite semichemical (NSSC) pulping process, wood chips are pretreated with sodium sulfite and sodium carbonate solution. This pretreatment dissolves a part of hemicellulose and lignin from wood chips. The spent liquor (SL) that is produced in the pretreatment process contains a considerable amount of lignosulfonate and hemicelluloses, but SL is generally treated in the wastewater effluent system of the mills (i.e. lignocelluloses are wasted). In this paper, these lignocelluloses were separated from SL with organic solvents, and their thermal properties were determined. The results showed that the precipitates isolated from SL/acetone, SL/ethanol or SL/isopropyl mixtures with the weight ratio of 67/33 had the highest heating values of 18.61, 17.59 and 17.05 MJ/kg, respectively. The precipitates made from mixing acidified SL and solvents had lower heating values than those made from mixing untreated SL and solvents, which is likely due to the relatively high ash content of the precipitates made from mixing acidified SL and solvent. The theoretical and experimental heating values of precipitates were compared in this work. The precipitates displayed lower ignition temperatures compared with other biomass-based solid fuels, implying that the combustion of precipitates would require lower activation energies. [ABSTRACT FROM AUTHOR]

Background: Hot water hydrolysis process is commercially applied for treating wood chips prior to pulping or wood pellet production, while it produces hydrolysis liquor as a by-product. Since the hydrolysis liquor is dilute, the production of value-added materials from it would be challenging. Results: In this study, acidification was proposed as a viable method to extract (1) furfural and acetic acid from hot water hydrolysis liquor and (2) lignin compounds from the liquor. The thermal properties of the precipitates made from the acidification of hydrolysis liquor confirmed the volatile characteristics of precipitates. Membrane dialysis was effective in removing inorganic salts associated with lignin compounds. The purified lignin compounds had a glass transition temperature (Tg) of 180-190 °C, and were thermally stable. Conclusions: The results confirmed that lignin compounds present in hot water hydrolysis liquor had different characteristics. The acidification of hydrolysis liquor primarily removed the volatile compounds from hydrolysis liquor. Based on these results, a process for producing purified lignin and precipitates of volatile compounds was proposed. [ABSTRACT FROM AUTHOR]

Background: Despite the introduction of direct oral anticoagulants, the search for new oral anticoagulants remains an urgent task., Objective: By using docking and scoring, based on physical methods, simple chemical rules, methods of synthesis, and activity measurement, develop new low-molecular-weight inhibitors of factor Xa, which are potential anticoagulants., Methods: The development of leads was based on chemical synthesis and structure-based drug design methods. The basic idea was to combine the two approaches: one based on predictive modeling and the other based on the experimental data., Results: In this study, we developed some nanomolar leads. Further chemical modification improved the inhibition constant by more than one order., Discussion: The method proposed in this paper, as well as other methods, includes virtual screening, chemical synthesis, and activity measurement. However, the most time-consuming process in this method (chemical synthesis) was simplified, and the cost was reduced to the extent that was allowed; a very simple chemical reaction was chosen, i.e., the formation of an amide bond., Conclusion: In this work, we demonstrated how using simple chemical rules based on the structurebased drug design, substances with a nanomolar concentration of activity can be developed., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: Volatile (inhaled) anesthetic agents have cardioprotective effects, which might improve clinical outcomes in patients undergoing coronary-artery bypass grafting (CABG)., Methods: We conducted a pragmatic, multicenter, single-blind, controlled trial at 36 centers in 13 countries. Patients scheduled to undergo elective CABG were randomly assigned to an intraoperative anesthetic regimen that included a volatile anesthetic (desflurane, isoflurane, or sevoflurane) or to total intravenous anesthesia. The primary outcome was death from any cause at 1 year., Results: A total of 5400 patients were randomly assigned: 2709 to the volatile anesthetics group and 2691 to the total intravenous anesthesia group. On-pump CABG was performed in 64% of patients, with a mean duration of cardiopulmonary bypass of 79 minutes. The two groups were similar with respect to demographic and clinical characteristics at baseline, the duration of cardiopulmonary bypass, and the number of grafts. At the time of the second interim analysis, the data and safety monitoring board advised that the trial should be stopped for futility. No significant difference between the groups with respect to deaths from any cause was seen at 1 year (2.8% in the volatile anesthetics group and 3.0% in the total intravenous anesthesia group; relative risk, 0.94; 95% confidence interval [CI], 0.69 to 1.29; P = 0.71), with data available for 5353 patients (99.1%), or at 30 days (1.4% and 1.3%, respectively; relative risk, 1.11; 95% CI, 0.70 to 1.76), with data available for 5398 patients (99.9%). There were no significant differences between the groups in any of the secondary outcomes or in the incidence of prespecified adverse events, including myocardial infarction., Conclusions: Among patients undergoing elective CABG, anesthesia with a volatile agent did not result in significantly fewer deaths at 1 year than total intravenous anesthesia. (Funded by the Italian Ministry of Health; MYRIAD ClinicalTrials.gov number, NCT02105610.)., (Copyright © 2019 Massachusetts Medical Society.)

Background: Factor Xa (FXa) is known to play a central role in blood coagulation cascade and considered to be one of the most attractive targets for oral anticoagulants of new generation., Objective: Our approach for the development of directly acting oral anticoagulants (DOAC), FXa inhibitors was demonstrated in this work., Method: Chemical synthesis is the base of our approach for the development of potential inhibitors. In this work, the substances like R1-(CONH)-R2-(CONH)-R3 are being developed, using previously described docking and screening methods, where R1, R2 and R3 are some chemical groups and (CONH) are amide bonds connecting R1, R2 and R3. The direction of amide bond (CONH) could be arbitrary for R1, R2 and R2, R3., Results: Chemical modifications were made in the frame of the results, taking into account the structure of FXa, chemical synthesis capabilities, as well as patentability of the target compounds. Subnanomolar potency of several developed compounds was achieved. Several analyzers and various testing-suites have been used to measure the concentration that doubled the prothrombin time (PTx2). Moreover, in human plasma the PTx2 concentration of the compound 217 (DD217) turned out to be 80±20 nM. The compound efficacy has proved by in vivo assays including oral administrations in rats, rabbits and monkeys., Conclusion: The pharmacodynamic profile of DD217 for oral administration in cynomolgus monkeys proves the efficacy of the compound, which makes it promising for the future preclinical trials., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Pocket hematoma (PH) is a common complication of implantations of cardiac electrophysiological devices with occurring at a particularly high rate in patients on oral anticoagulation or antiplatelet treatment. Different pharmacological agents with hemostatic effect are used to avoid PH. We supposed that the vasoconstrictor effects of epinephrine may reduce bleeding extent and be effective in prevention of PH. Maitre is the first clinical trial conducted with an aim to show the safety and efficacy of epinephrine in PH prophylaxis. We randomized 133 patients to receive either epinephrine or saline solution, which were added to a local anesthetic administered during pacemaker implantation. In cases of diffuse bleeding a method of pocket drainage was effectively used. Results showed that risk of PH was significantly higher in the group receiving epinephrine. We conclude that a local epinephrine effect may lead to a false impression of adequate hemostasis and force a surgeon to refuse from drainage insertion.