Electroencephalography: Evaluation of Neurologic Disorders

Electroencephalography (EEG) is a useful diagnostic and prognostic tool for evaluation of patients with epilepsy, encephalopathy, focal lesions, coma, or brain death. The 3 main types of epileptiform discharges are spikes, sharp waves, and spike-and-wave discharges. Spikes have a steep ascent and descent and are brief (duration ≤70 milliseconds). Sharp waves, in contrast, are longer (70-200 milliseconds). Spike-and-wave discharges consist of a spike followed by an after-coming slow wave. All the discharges may occur singly or in trains, and any may be present in either focal epilepsy or generalized epilepsy.

Electroencephalography: Basic Concepts

Electroencephalography (EEG) is a useful diagnostic and prognostic tool for evaluation of patients with epilepsy, encephalopathy, focal lesions, coma, or brain death. The 3 main types of epileptiform discharges are spikes, sharp waves, and spike-and-wave discharges. Spikes have a steep ascent and descent and are brief (duration ≤70 milliseconds). Sharp waves, in contrast, are longer (70-200 milliseconds). Spike-and-wave discharges consist of a spike followed by an after-coming slow wave. All the discharges may occur singly or in trains, and any may be present in either focal epilepsy or generalized epilepsy.

Optimization of the Nutrient Medium for Flammulina velutipes Submerged Biomass Production and Micromorphology of Its Mycelium

Based on the assessment of the trophic needs of basidiomycete Flammulina velutipes and the optimization of the composition of the nutrient medium using design of experimental approach, the yield of the submerged biomass of the fungus was increased to 41 g/L, the duration of the cultivation process was reduced to 5 days. For this purpose, the 24 full factorial design, the Box–Wilson steep ascent method and the construction of the response surface were used. Using the method of scanning electron microscopy, it was shown that the studied F. velutipes strain grew in the form of small spherical pellets with a diameter of 1–2 mm on an optimized medium. The surface of the pellets was loose; the inner part was filled with hyphae tightly adjacent to each other. The center of the pellets had no cavity. F. velutipes pellets were formed by septate hyphae with clamp connections. The micromorphological characteristics of the submerged F. velutipes mycelium ensured a high diffusion of nutrients and oxygen into the pellets and their maximum filling of the volume of the culture medium.

Determining the Optimal Mode of the Inconel 718 Alloy Deposition at a Direct Laser Deposition Plant

The paper describes determining the optimal direct laser deposition mode when processing the results of a two-factor experiment by the steep ascent method. The dependence of the ultimate tensile strength on the volumetric energy density and the lateral pitch was chosen as the target function.

Strain-driven autonomous control of cation distribution for artificial ferroelectrics

In past few decades, there have been substantial advances in theoretical material design and experimental synthesis, which play a key role in the steep ascent of developing functional materials with unprecedented properties useful for next-generation technologies. However, the ultimate goal of synthesis science, i.e., how to locate atoms in a specific position of matter, has not been achieved. Here, we demonstrate a unique way to inject elements in a specific crystallographic position in a composite material by strain engineering. While the use of strain so far has been limited for only mechanical deformation of structures or creation of elemental defects, we show another powerful way of using strain to autonomously control the atomic position for the synthesis of new materials and structures. We believe that our synthesis methodology can be applied to wide ranges of systems, thereby providing a new route to functional materials.

MODELING STATISTICAL RELATIONS BETWEEN THE CONSUMPTION OF EDIBLE OIL OF VACUUM-PISTON TYPE DOUGH DIVIDING MACHINES WITH WEAR SURFACES

The most complex operation in the technological process of bread production is the division of the finished dough into blanks of the same mass. Vacuum-piston type dough separators perform this operation. Under operating conditions, the service life of the machines is 30-40 percent lower than the manufacturer's stated one. (Research purpose) The research purpose is in studying the permissible values of wear on the working surfaces of parts of vacuum-piston type dough dividing machines without repair. (Materials and methods) The article considers the method of multiple regression, which consists in studying the relationship between the maximum wear of the working surfaces of parts and the consumption of edible oil to determine the permissible sizes of parts of dough-dividing machines without repair. The parts were measured in several cross-sections in width and height. The sections were selected at the points of contact of the parts when they were moved relative to each other during the working stroke. (Results and discussion) The article presents a statistical relationship between the consumption of edible oil and the significantly affecting wear of the working surfaces of the parts of the dividing device of dough dividing machines. The values of permissible wear on the working surfaces of parts were determined by the method of steep ascent. (Conclusions) Using the method of multiple regression, the received linear regression equation adequately describes the relationship of the consumption of edible oil with the wear surfaces of separating device of TD-4 vacuum-piston type dough dividing machines. Authors determined the wear on the surfaces of parts of dividing devices and their influence on the dependent variable, the consumption of edible oil. The obtained values are fundamental for fault detection and the choice of a method for restoring worn surfaces of parts.

SYNTHESIS OPTIMIZATION OF 6-NITRO-3,4-DIHYDROQUINAZOLINE-4-ONE

A method for the synthesis of the substance 6-nitro-3,4-dihydroquinazolin-4-one has been developed. Quantitative determination of the target product was carried out spectrophotometrically using an SF-46 instrument. As a solvent, 0.1 mol/l HCl was used. A 0.1 mol/l hydrochloric acid solution was used as a comparison solution. The optical density of the standard and test samples was measured at a wavelength of 254 nm. The synthesis conditions of 6-nitro-3,4-dihydro-quinazolin-4-one were studied. The structure of the obtained product was studied by IR, Mass, 1H, 13C NMR spectroscopy, and the structure of the synthesized compound was also established. The main factors that influence the process of producing 6-nitro-3,4-dihydroquinazolin-4-one are identified. The process is optimized by the method of mathematical planning of the experiment. A mathematical model is drawn up. And the regression equation is calculated. A steep ascent along the response surface was carried out and optimal process conditions were found: temperature, time, quantitative ratio of the starting materials. It has been established that the main factor affecting the nitration process of 3,4-dihydroquinazolin-4-one is the temperature of 40 ºC and the reaction time is 4.5 h. Note that at a higher temperature, according to the analysis, a significant amount of dinitro derivative is formed, as a reaction byproduct.

The Experimental Determination of Optimum Parameters of the Equipment for Processing Grain in Preparation for Grinding

Introduction. Modern technology of grain processing pays special attention to the qualitative and efficient preparation of grain for milling. At small enterprises with a reduced technological process, this is almost the only way to improve product yield and quality. Without proper multi-stage preparation of grain for milling at small enterprises, it is impossible to achieve the required quality and quantity of products produced by industrial mills. Grain peeling is one of the most effective ways to clean the surface from dirt and remove outer shells. The removal of outer shells allows increasing the yield of high-grade flour at reduced milling diagrams. The efficiency of the peeling process is significantly infuencet by the design and operating parameters of the peeling machine. The purpose of this work is the experimental determination of optimal conditions for grain processing in the peeling and drying machine (the optimal combination of factors). Materials and Methods. To determine optimal conditions for grain processing in the peeling and drying machine, the method of extreme planning of the experiment was applied. The method of random balance was used to select the most significant factors based on their influence on the optimization parameter. The method of steep ascent on the response surface (the Box – Wilson method) was used to find the optimum area (the planning matrix was realized and statistical analysis of results and steep ascent on the response surface was carried out). Verification of the results was carried out on the software Statistica 10.0. Results. On the basis of experiments, a mathematical model of the technological process of wheat processing in the peeling and drying machine there were obtained, which linked the structural and mode parameters of the machine with the humidity of the treated grain. The results of the experiment confirmed the operability of the developed machine when working with high-humidity grain; they are fundamental for the machine’s further modernization. Discussion and Conclusion The analysis of the controlled factor dispersion diagram allowed us to select the most significant of them based on influence on the selected optimization parameter, the white flour color obtained from the treated grain. As a result of the evaluation of experimental data of the conducted studies, the design and mode parameters of the developed machine were determined, corresponding to the areas of the optimal optimization parameter: shaft rotation speed is 1400 rpm, angle of inclination of stamping on the sieve drum is 15 degrees, the initial moisture content of the processed grain is 15.50%, and the machine productivity does not exceed 700 kg/h.

Assessment of Technical Condition of C Series Power Hydraulic Cylinders of Mounted Hydraulic Systems of Tractors

Introduction. The existing methods of assessing the technical condition of power hydraulic cylinders do not allow one to conclude about the need to restore worn surfaces of parts. The data on limit values of wear of parts (wear and tear value at which a decision is made to repair) in technical requirements to overhaul and other technical documentation of hydraulic cylinders are not currently available. The aim of the study is to determine limit values of wear of working surfaces of hydraulic cylinder parts of C series. Materials and Methods.To assess the technical condition of hydraulic cylinders used, the authors developed a device on the basis of the stand KI-28097M-GOSNITI, equipped with an independent hydraulic station and load hydraulic cylinder, at which bench tests were carried out in the operation of С series hydraulic cylinders to determine overall efficiency values. Results. Results of bench and micrometer tests of the former hydraulic cylinders of the С series (С75/30, С90/30, С100/40) are presented. The regression model of the relationship between total efficiency of C series hydraulic cylinders (С75/30, С90/30, С100/40) and wear of working surfaces of parts was obtained. According to this regression model obtained using the method of steep ascent, limit values of wear of the working surfaces of C series hydraulic cylinder parts (С75/30, С90/30, С100/40) were determined. Discussion and Conclusion.19,5 % of hydraulic cylinders of С series (С75/30, С90/30, С100/40) were operated in an out-of-limit condition. In case of technical service companies carrying out the input control of to-be-repaired hydraulic cylinders, limit values of wear for hydraulic cylinder surfaces, determined by the method of steep ascent, allow for making proper decisions on the need of their restoration.