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In gliomas, expression of certain marker genes is strongly associated with survival and tumor type and often exceeds histological assessments. Using a human interactome model, we algorithmically reconstructed 7494 new-type molecular pathways that are centered each on an individual protein. Each single-gene expression and gene-centric pathway activation was tested as a survival and tumor grade biomarker in gliomas and their diagnostic subgroups (IDH mutant or wild type, IDH mutant with 1p/19q co-deletion, MGMT promoter methylated or unmethylated), including the three major molecular subtypes of glioblastoma (proneural, mesenchymal, classical). We used three datasets from The Cancer Genome Atlas and the Chinese Glioma Genome Atlas, which in total include 527 glioblastoma and 1097 low grade glioma profiles. We identified 2724 such gene and 2418 pathway survival biomarkers out of total 17,717 genes and 7494 pathways analyzed. We then assessed tumor grade and molecular subtype biomarkers and with the threshold of AUC > 0.7 identified 1322/982 gene biomarkers and 472/537 pathway biomarkers. This suggests roughly two times greater efficacy of the reconstructed pathway approach compared to gene biomarkers. Thus, we conclude that activation levels of algorithmically reconstructed gene-centric pathways are a potent class of new-generation diagnostic and prognostic biomarkers for gliomas.

Background: Kidney injury is a common feature of COVID-19 infection, but serum creatinine (SCr) is not a sensitive or specific marker of kidney injury. We hypothesized that measurement of molecular markers of tubular injury can diagnose COVID-19 associated kidney injury and predict a poor prognosis. Methods: This is a prospective cohort study of 444 consecutive COVID-19 patients in a New York City Emergency Department recruited in March and April, 2020. Urine and blood were collected simultaneously at hospital admission (median time of day 0, IQR 0-2 days) and within 1 day of a positive SARS-CoV-2 test in 70% of patients. Urine NGAL and KIM-1 assays were blinded to clinical data. Primary outcomes included the diagnosis of Acute Kidney Injury (AKI) as defined by AKIN criteria, as well as its duration and severity. Secondary outcomes included death, dialysis, shock, respiratory failure, and length of hospital stay. Kidney biopsies from COVID-19 patients were examined for biomarker gene expression. Results: Elevated urinary NGAL (uNGAL) levels were associated with SCr based AKI (267±301 vs. 96±139 ng/mL, P=1.6x10-10). uNGAL level >150 ng/mL had 80% specificity and 75% sensitivity to diagnose AKIN stage 2 AKI or higher. Higher uNGAL levels were associated with sustained AKI [aOR per SD of uNGAL (95%CI): 2.67 (1.81-4.06), P=1.8x10-6], need for dialysis (aOR: 3.67 (1.89-7.57), P=2.2x10-4), shock (aOR: 1.64 (1.26-2.15), P=2.9x10-4), prolonged length of stay (aHR: 1.22 (1.09-1.36), P=4.8x10-4), and death [aOR=1.62 (1.19-2.24), P=2.5x10-3], independent of baseline SCr and pre-existing co-morbidities. These associations were also preserved after adjusting for proteinuria measured in the same urine sample. NGAL is typically transcribed by distal nephron segments but in COVID-19 kidney biopsies with widespread histopathologic acute tubular injury (ATI), NGAL mRNA expression included proximal tubules. Conclusions: Elevated uNGAL in patients admitted with acute COVID-19 was associated with the development of AKI, increased severity and duration of AKI, the degree of histopathological acute tubular injury, shock, prolonged hospitalization, need for dialysis, and death.

The task of forecasting the dynamics of changes in the rates of financial instruments is relevant, since its solution would reduce risks and increase the profitability of operations in financial markets. According to the classical concept of the nature of markets, their pricing processes are stochastic and cannot be predicted. In recent years the general trend in scientific research is econo-physics – the science in the convergence of economics and physics that uses the approaches typical for physical phenomena investigation to analyze economic systems. One of these approaches is fractal analysis. It is based on the fractal market hypothesis, which states that the dynamics of changes in prices of financial instruments is subject to power laws and their prediction is possible. The fractal of financial series is expressed in their property to maintain the trend of changes (so called long memory) for a long time. There are modifications of econometric models that take into account the fractal properties of time series. Their use in domestic markets has not been studied enough: there are few examples of successful predictions obtained using such models; there are no works that focus on the comparison of fractal and non-fractal models on sufficiently large arrays of price data, and it does not allow us to say with certainty about the superiority of models that take into account the fractal properties of series. The main idea of the study is to compare the prediction accuracy of econometric models and their fractal extensions using the same data. The purpose of the research is to verify the hypothesis that taking into account the fractal of financial series, while all other things are equal, allows us to obtain better and more accurate forecasts of financial instruments. The following approaches and methods have been used: fractal analysis and econometric models (ARIMA, GARCH), as well as their modifications, taking into account the property of long memory. For the first time, the accuracy of a large number of similar fractal and non-fractal models has been compared with differences in the nuances of fractal parameter estimation on the same data, the problems of determining the boundaries of financial series sections with different fractal properties and selecting a series (initial or transformed) for evaluating the operator of fractional differentiation of the ARFIMA model have been formulated. We have obtained the following results. The hypothesis of the best predictive ability of fractal models is not rejected, since in most cases the forecast accuracy of ARFIMA and ARFIMA-GARCH was higher than the forecast accuracy of ARIMA and GARCH. The hypothesis of a variable fractal structure of financial series has been confirmed, as evidenced by the variable graphs of local fractal dimensions. The hypothesis of the advantage of models with long memory over models with short memory has not been rejected, since the ARIMA model has demonstrated the least accuracy of forecasts. The hypothesis of the alteration of the fractal properties of time series in the transformation has been confirmed, that has been proven with different values of the Hurst exponent and different graphics of local dimensions. We did not manage to confirm the following hypotheses: the use of local fractal indicators instead of global ones to calculate the fractional differentiation parameter increases the accuracy of forecasts; with the growth of the forecast length, its accuracy decreases; sections of series with long memory are better modeled and forecasted. Possible directions for further research have been formulated: to develop a method for determining the boundaries of local areas of financial series with different fractal properties; to formulate recommendations on which series (initial or transformed) should be evaluated by the operator of fractional differentiation of the ARFIMA model; to verify unconfirmed hypotheses with a change in the research methodology; to study various fractal modifications of GARCH models and identification of conditions for their applicability.

The endocrine system plays a key role in the pathogenesis of the non-infectious pathology of dairy cows. However, the role of a number of hormones in pathology is not clear. These hormones include insulin-like growth factors and leptin. The insulin-like growth factor is synthesized predominantly in the liver in response to an increase in the level of somatotropic hormone in the blood. According to its physiological properties, it is close to insulin, structurally similar, has common receptors that trigger the same chain of reactions: stimulates transport of amino acids and glucose in the muscles, increases the sensitivity of cells to insulin, in adipose tissue, transport glucose, oxidation of glucose to carbon dioxide, the inclusion of glucose in lipids. Leptin is synthesized by adipocytes, and its main physiological function is to reduce the synthesis of macroergic compounds and increase energy expenditure. Circulating in the blood, it helps to maintain an optimal level of glucose, which is necessary for the energy needs of the body. The purpose of this study was to investigate the concentration of insulin-like growth factor, leptin, glucose, pyruvate and lactate in the blood of cows under secondary osteodystrophy, ketosis and hepatodistrophy. This will give an opportunity to better understand the pathogenesis and create theoretical preconditions for the development of informative diagnostic tests and effective means of treatment. The experiment was conducted on dairy cows, analogues by age, breed, productivity and physiological state. According to clinical features, urine analysis and values of biochemical parameters of blood of experimental cows were divided into four groups: 1 – clinically healthy cows, 2 – patients with osteodystrophy, 3 – patients with ketosis, 4 – patients with hepatodistrophy. The obtained results of research indicate that the internal non-contagious pathology in dairy cows deficiency of exchange energy is recorded, which induces an increase in the activity of gluconeogenesis and is expressed by lowering the concentration of glucose and increasing the content of pyruvate and lactate. At the same time, a decrease in the level of insulin-like growth factor and leptin was found. The lowest level of insulin-like growth factor and leptin was determined by ketosis. The decrease in the level of tissue hormones in the blood plasma of cows under osteodystrophy was within the statistical error.

Aim. To investigate the plasma concentrations of insulin-like growth factor (IGF, somatomedin C), triiodothyronine, thyroxine and insulin in cows during prepartum and postpartum periods. Methods. Enzyme- linked immunosorbent assay, clinical and statistical methods. Results. It was demonstrated that the plasma concentration of IGF, triiodothyronine, thyroxine, and insulin is lower in postpartum cows compared to the interlactation ones. Strong positive correlation dependence (r = 0.7) between the levels of thyroxine and somatomedin C was found on the 2 nd –4 th day after calving. The plasma concentration of all the investigated hormones increased in cows on the 10-14 th day of postpartum period and remained stable until days 30–40. Strong correlation dependence between the levels of somatomedin C and insulin (r = 0.7) was found on the 10- 14 th day of the postpartum period. Conclusions. It was determined that somatomedin C is one of the energetic balance regulators in dairy cows.

Aim. To investigate plasma amino acid composition in dairy cows after ketosis conventional (oral administra- tion of propylene glycol, intravenous injection of glucose and insulin) and proposed treatment (oral administra- tion of propylene glycol, intravenous injection of “Remivital”). Methods. Study was performed on high yield- ing dairy cows with clinical ketosis during their 2 nd to 4 th lactation with milk yield above 8000 L per previous lactation. Content of free amino acids was determined in plasma before and after treatment using amino acid analyzer. Results. Lowering of the level of ketogenic amino acids was revealed after conducted treatment as well as increase in the level of glycogenic and branched amino acids. Signifi cant lowering of the level of meth- ylhistidine gives evidence of decreased catabolism of contractile proteins. Conclusions. Proposed treatment regimen has proven to be superior, since signifi cantly higher level of ornithine and lower level of citrulline were revealed after administration of conventional regimen, which gives evidence of problems in disposal of ammonia and lactate. Moreover, in case of administration of traditional scheme, the concentration of markers of catabolism of contractile proteins was still high, in contrast with such in animals, which were administered proposed regimen, and high concentration of isoleucine contributes to aggravation of ketoacidosis.

The article considers modeling of modern heat exchange systems which use thermal energy for its beneficial use. The proposed mathematical model makes it possible to investigate systems with utilization of thermal energy. The article presents the results of simulation of heat exchange processes using heat energy recovery for internal combustion engines.

IR spectroscopic techniques widely used to determine the thickness and refractive index of layers and thin films of various materials are adapted for determining those of hydrogenated silicon layers. Based on a literature analysis, three formulas are chosen which enable the refractive index and thickness of such layers to be determined from reflection and transmission spectra. The formulas are applicable, with some restrictions, to other samples in the form of relatively transparent layers (films) on transparent substrates. Experimental data are presented that illustrate the use of the formulas.

The article considers the opportunity of utilizing sludge wastes, generated at the vanadic pentoxide and ferrovanadium alloys production cycle, in walling ceramics production. The considered materials belong to polymineral systems in their chemical and mineral composition, and contain the crystalline phases – calcium carbonate and sulphate, and the iron-containing components – hematite, wustite, the sulphate form of hydrated calcium sulfoferrite and the residual amount of lime. The metal oxides are contained in the amorphized state. The ferriferrous concentrate sludge, added to the raw mix, due to the high content of iron compounds in it, demonstrates mineralizing and fluxing properties. At baking the raw mix, containing limestone-gypseous composition, the processes of intensive release of such gases as CO2 and water vapor is observed, as the products of carbonate and sulphate components. The adding of sludge materials to the raw mix composition results in the alteration of the color of the obtained samples from red-brown to black-brown. The adding of sludge to the raw charge of ceramic brick in amount of 3–5% of weight doesn't impair its physical and mechanical characteristics. The increase of its content to 30% causes the porous structure formation and reduces the density and strength characteristics of materials. The obtained wall ceramic products can be used as structural and heat-insulating materials for making enclosing structures and interior partitions.

Proton-implanted (100) KEF-4.5 (phosphorus-doped) silicon wafers 460 μm in thickness have been studied by IR spectroscopy in an on-axis geometry. The implantation process has been run at increased proton energies and current densities to rather high implant doses, up to 7.1 × 1017 H+/cm2. The results are used to identify the structure of chemical bonds in the hydrogen centers produced by the implantation and subsequent annealing at 550°C. We show that the assignment of absorption bands to particular Si-H x (x = 1–3) bonds must take into account the substrate temperature during the implantation process and the annealing temperature.

A mathematical model and parametric analysis are presented for evaluating the effects of axiradial rotor wheels in multistage compressors for the purpose of reducing the number of stages, improving the gas-dynamic characteristics, reducing the mass and size of the components, and reducing the metal required in their fabrication. The model calculates the ideal flow, the boundary layer at the front and rear sides of the blade, the breakaway flow, the viscous axisymmetric flow in the working wheel, and the losses. The equations for relative velocity distribution of nonviscous flow in the flow-through section of an axiradial rotor were obtained from an equation for the moments of the quantity of movement in integral form in a relative system of coordinates. The scheme for calculating the flow parameters and losses in a twin-unit stage is presented. Recommendations are specified for parameters for the distribution of velocities for profiling the wheels.

no majestic road to the front, no regiment ready for battle and no end in a deathly engagement on the threshold of immortality. No, the war took my soul and forgot it midways. And over it rolled contingents in the acrid smoke, thorny dust of marches, evacuations, preventing my soul to rise. At night above head thundered by echelons of crying children who lost their mothers en route, wheels out of their minds whizzed by. Hospital trains have dragged my soul all the way around Russia. Towns, cities, towns ... Woods and barefooted clusters of trees . . . How your frosts burn! How your bluish snowstorms smoke! At night the wounded moan With the far off voice of an ancient friend.