Rapid eutectic growth: from rod growth to diffusionless solidification

Numerous experimental data on the rapid solidification of eutectic systems exhibit the formation of metastable solid phases with the initial (nominal) chemical composition. This fact is explained by the suppression of eutectic decomposition due to diffusionless (chemically partitionless) solidification beginning at a high but finite growth velocity of crystals. In the present work, a model is suggested for the diffusionless growth to analyse the atomic diffusion in the rod eutectic couples growing into supercooled liquid. A simplified calculating method for the equation related to the Bessel function in the solution of the growth of rod eutectics is obtained. This method can also be used in the calculation of other rod eutectic growth models. This article is part of the theme issue ‘Transport phenomena in complex systems (part 2)’.

Rodent Brain Pathology, Audiogenic Epilepsy

The review presents data which provides evidence for the internal relationship between the stages of rodent audiogenic seizures and post-ictal catalepsy with the general pattern of animal reaction to the dangerous stimuli and/or situation. The wild run stage of audiogenic seizure fit could be regarded as an intense panic reaction, and this view found support in numerous experimental data. The phenomenon of audiogenic epilepsy probably attracted the attention of physiologists as rodents are extremely sensitive to dangerous sound stimuli. The seizure proneness in this group shares common physiological characteristics and depends on animal genotype. This concept could be the new platform for the study of epileptogenesis mechanisms.

Stages of launching a biological treatment plant at the wastewater treatment facilities with dosing easily oxidable organic matter

Рассмотрены вопросы, связанные с проведением пусконаладочных работ биоблока станции очистки хозяйственно-бытовых и близких к ним по составу сточных вод при пробном пуске в эксплуатацию очистных сооружений. Подробно рассмотрены этапы пусконаладочных работ биоблока очистных сооружений с «затравкой» активным илом из действующих биологических очистных сооружений и с дозировкой легкоокисляемой органики. Описан состав оборудования станции КОС-9 производства «Гермес Групп». Рассмотрены все этапы пусконаладочных работ биоблока на примере запуска очистных сооружений КОС-9 с привлечением многочисленных опытных данных. Определены периоды этапов пусконаладки биоблока. Приведены проблемы наладки биоблока и пути их решения с достижением требуемого результата. Технология, используемая на станции, обеспечивает очистку сточных вод, соответствующую требованиям, предъявляемым к выпуску очищенных стоков в водоем рыбохозяйственного значения. Issues related to commissioning a biological treatment plant at the facilities for household and similar in composition wastewater treatment during the trial start of the treatment facilities are considered. The stages of commissioning a biological treatment plant at the wastewater treatment facilities with «inoculating» activated sludge from the operating biological treatment facilities and with dosing easily oxidable organic matter are considered in detail. The equipment configuration of the WWTP-9 produced by Germes Group is described. All stages of the biological treatment plant commissioning are considered through the example of the start-up of WWTP-9 with the use of numerous experimental data. The periods of biological treatment plant commissioning stages have been determined. The problems of adjusting the biological treatment plant and the ways of their elimination to achieve the required result are presented. The technology used at the WWT facilities provides for the effluent quality that meets the requirements for the discharge into a water body of commercial fishing importance.

The Role of Secondary Brain Insults in Status Epilepticus: A Systematic Review

(1) Background: Little is known about the impact of pathophysiological mechanisms that underlie the enhancement of excitotoxicity and the neuronal consequences of status epilepticus (SE), as well as the clinical consequences of secondary brain insults (SBI) in patients with SE on outcome; (2) Methods: Electronic searches were conducted in May 2020 using Medline via PubMed, Embase, and Google Scholar (#CRD42019139092). Experimental studies of animals or randomized, observational, controlled trials of patients with SE in indexed journals were included. There were no language or date restrictions for the published literature included in this review. Information was extracted on study design, sample size, SBI characteristics, and primary and secondary outcomes, including the timing of evaluation; (3) Results: Among the 2209 articles responding to our inclusion criteria, 56 were included in this systematic review. There are numerous experimental data reporting the deleterious effects associated with each of the SBI in animals exposed to SE. In humans, only the effect of target temperature management in hypothermia (32–34 °C) has been explored. (4) Conclusions: There is little experimental evidence that favors the control of secondary brain insult after SE. Further studies are required to assess the neuroprotective interest of secondary brain insult control after SE in humans.

ANALYSIS WEAR OF WHEEL PAIRS ULAANBAATAR WAGONS RAILWAY

The article is devoted to the analysis of the wear of the crest of the wheel pairs of freight cars of the Ulanbator Railway. Based on numerous experimental data, the factors affecting wear are investigated. According to the change in ridge thickness, the wear rate of the first wheelset over 5000 km is less than the third, and the wear of the second wheelset is less than the fourth. Subsequent 10,000 km and 30,000 km of run, this indicator changes in the opposite direction, therefore, it is necessary to change the sequence of wheelsets.

HMGA Proteins in Stemness and Differentiation of Embryonic and Adult Stem Cells

HMGA1 and HMGA2 are chromatin architectural proteins that do not have transcriptional activity per se, but are able to modify chromatin structure by interacting with the transcriptional machinery and thus negatively or positively regulate the transcription of several genes. They have been extensively studied in cancer where they are often found to be overexpressed but their functions under physiologic conditions have still not been completely addressed. Hmga1 and Hmga2 are expressed during the early stages of mouse development, whereas they are not detectable in most adult tissues. Hmga overexpression or knockout studies in mouse have pointed to a key function in the development of the embryo and of various tissues. HMGA proteins are expressed in embryonic stem cells and in some adult stem cells and numerous experimental data have indicated that they play a fundamental role in the maintenance of stemness and in the regulation of differentiation. In this review, we discuss available experimental data on HMGA1 and HMGA2 functions in governing embryonic and adult stem cell fate. Moreover, based on the available evidence, we will aim to outline how HMGA expression is regulated in different contexts and how these two proteins contribute to the regulation of gene expression and chromatin architecture in stem cells.

Resolving velocity ambiguity of two coded pulse in broad-band acoustic Doppler current profiler

Broad-band Acoustic Doppler Current Profiler (BBADCP) adopts short-sequence coded pulse to measure high velocity. Short-sequence coded pulse has large measurable velocity, so it is not easy to have velocity ambiguity. But short coded pulse deteriorates the accuracy of the velocity. To obtain more accurate velocity, we adopt two coded pulse with a time lag. This paper analyzes the ambiguity velocity and velocity standard deviation of two coded pulse and single coded pulse, and gives a solution to resolve velocity ambiguity: single coded pulse which has a large ambiguity velocity due to the short time lag is used to establish a coarse estimate of the velocity, two coded pulsewhich has a long time lag is used to have a high accuracy velocity, then we combine the two velocities in a way to provide an accurate velocity. It has been demonstrated that the two coded pulse can reduce variance of velocity through analyzing numerous experimental data of pool. Meanwhile, the efficiency of method to solve ambiguity has been proved in accordance with multiple sets of data. Compared with the traditional methods, this method has good anti-noise performance and high single measurement accuracy.

Hydraulic conductivity of peat in Western Siberia

The paper aims at estimating hydraulic conductivity of peat. It is a complicated process since peat has some unique properties that are not typical for mineral soils. Other difficulties involve the lack of elaborated procedure for laboratory testing and data processing, high sensitivity of peat soils to external and internal factors; which leads to considerable fluctuation in peat hydraulic conductivity values. The specific properties of hydraulic conductivity in peat soils are proved by numerous experimental data. The article also provides the permeability values for the most typical peat species in Western Siberia. The obtained data allow forecasting peat soil response to the development of peatlands.

MODELING OF THE SURFACE TENSION OF COLLOIDAL SUSPENSIONS

Surface tension is one of the fundamental properties of the colloids, which can be altered by concentration and size of colloidal particles. In the current work, modeling of the surface tension of suspension as it would be analyzed by maximum bubble pressure method has been performed. A new modified equation to correlate the surface tension with the bubble pressure is derived by applying fundamental thermodynamic relation considering the presence of particles in suspension and curvature of the interface between the particles and bubbles inside liquid. Moreover, the change of particles concentration in air–water interface due to capillary force is also considered. The predicted surface tension using the developed model has been verified by numerous experimental data with deviation less than 5% in most of cases. It was found that the calculated surface tension is altered by contact angle and particle radius as well as particle concentration. The obtained model may have potential application to predict the surface tension of colloidal suspension.

Is not it time to go back to Tg Tamman?

Based on the analysis of numerous experimental data shows that the generally accepted today, the glass transition temperatureTg is not. It was the result of borrowing from tammana symbolTg, is meant the temperature of viscous flow liquid transformation into solid brittle glassy state, and use it together symbolTw, means the temperature tammana bend on the dependence of the «property-temperature» glass-forming substances aboveTg of tammana. On the basis of the application of polymer-polymorphing representations of the structure of glass-forming substances are disclosed physico-chemical nature of the temperature curveTw (conventional Segodnya), which is the temperature of the reverse direction interconversion of nanofragments patterns (polymorphical) high and low temperature polymorphs that coexist in the vitreous substance. The discovery in recent decades prezentatsionnogo effect located as tammanaTg, is below the standardTg,Tg confirms the truth of tammana characterized by increasedspecific heat of the heated glass.