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Caenorhabditis elegans has become a key model organism within biology. In particular, the transparent gut, rapid growing time, and ability to create a defined gut microbiota make it an ideal candidate organism for understanding and engineering the host microbiota. Here we present the development of an experimental model that can be used to characterize whole-cell bacterial biosensors in vivo. A dual-plasmid sensor system responding to isopropyl β-d-1-thiogalactopyranoside was developed and fully characterized in vitro. Subsequently, we show that the sensor was capable of detecting and reporting on changes in the intestinal environment of C. elegans after introducing an exogenous inducer into the environment. The protocols presented here may be used to aid the rational design of engineered bacterial circuits, primarily for diagnostic applications. In addition, the model system may serve to reduce the use of current animal models and aid in the exploration of complex questions within general nematode and host-microbe biology.

Genetic sex determination (GSD) can evolve from environmental sex determination (ESD) via an intermediate state in which both coexist in the same population. Such mixed populations are found in the crustacean Daphnia magna, where non-male producers (NMP, genetically determined females) coexist with male producers (MP), in which male production is environmentally inducible and can also artificially be triggered by exposure to juvenile hormone. This makes Daphnia magna a rare model species for the study of evolutionary transitions from ESD to GSD. Although the chromosomal location of the NMP-determining mutation has been mapped, the actual genes and pathways involved in the evolution of GSD from ESD remain unknown. Here, we present a transcriptomic analysis of MP and NMP females under control (female producing) and under hormone exposure conditions. We found similar to 100 differentially expressed genes between MP and NMP under control conditions. Genes in the NMP-determining chromosome region were especially likely to show such constitutive expression differences. Hormone exposure led to expression changes of an additional similar to 100 (MP) to similar to 600 (NMP) genes, with an almost systematic upregulation of those genes in NMP. These observations suggest that the NMP phenotype is not determined by a simple "loss-of-function" mutation. Rather, homeostasis of female offspring production under hormone exposure appears to be an active state, tightly regulated by complex mechanisms involving many genes. In a broader view, this illustrates that the evolution of GSD, while potentially initiated by a single mutation, likely leads to secondary integration involving many genes and pathways.

The article is about gas air stream modeling at a nozzle cross section of a turbomachine for steady and unsteady operating mode, the mathematical model is assigned, which describes acoustic processes in a turbomachine flow path and the ways of their improvement. The principles of aero-acoustic cartography complex systems creation are defined by means of acouto-electronic and they are accompanied by methods and means of gas dynamic stream parameter measurement in the flow path and at nozzle cross section of a turbomachine. The principles described make the control more informative and ease the algorithm creation for nondestructive method of rotor blade condition monitoring. Altogether it provides reliable data in conditions of gas air stream parametric and structural uncertainty both in controlled inside section of the flow path and in outlet section at a turbomachine cut. The tasks of monitoring point placement and the tasks of a field spatial distribution reconstruction are reviewed according to measurements in a discrete set of points separately. In complex approach the turbomachine acoustic field reconstruction is realized according to measurement data of optical fiber sensor outlet using the statistical approach only. The field reconstruction in 1D, 2D and 3D formats is presented as continuous functions of spatial coordinates according to measurements in a discrete set of points where a priori information about the field features is available.

The study of the welding process of asymmetric parts made of Ti-6A1-4V alloy was made to expand the field of application of the process of linear friction welding and to improve the use of technology of existing assemblies. During of the study, it was found that the process of welding T-joints has features in a longer duration of the unsteady stage and an increase in the amplitude value of the shear force during the steady state. Welded joints do not contain seam flaws over the area of the welded joint, which it made unnecessary to assign an allowance along the perimeter of the welded section. The change in conditions at the joint is expressed in an increase in the microhardness of the welded seam in comparison with the Ti-6A1-4V joints, which are produced by the traditional technology more than 50 HV.

Standard evolutionary theory, supported by mathematical modelling of outbred, dispersed populations predicts that ageing is not an adaptation. We recently argued that in clonal, viscous populations, programmed organismal death could promote fitness through social benefits and has, in some organisms (e.g. Caenorhabditis elegans ), evolved to shorten lifespan. Here, we review previous adaptive death theory, including consumer sacrifice, biomass sacrifice and defensive sacrifice types of altruistic adaptive death. In addition, we discuss possible adaptive death in certain semelparous fish, coevolution of reproductive and adaptive death, and adaptive reproductive senescence in C. elegans . We also describe findings from recent tests for the existence of adaptive death in C. elegans using computer modelling. Such models have provided new insights into how trade-offs between fitness at the individual and colony levels mean that senescent changes can be selected traits. Exploring further the relationship between adaptive death and social interactions, we consider examples where adaptive death results more from action of kin than from self-destructive mechanisms and, to describe this, introduce the term adaptive killing of kin. This article is part of the theme issue ‘Ageing and sociality: why, when and how does sociality change ageing patterns?’

The article presents the results of theoretical and experimental studies of new solution of the applied research task that consists in mathematical modelling of the interaction process of concave disk spring shanks and a soil medium, taking into account the random nature of soil response, in the form of a non-linear dynamic movement model. It has allowed for determining the optimal dynamic characteristics and the design parameters of the spring shanks of a disk operating element: rigidity, reduced mass, frequency and amplitude of oscillations. A structural diagram of the interaction process of a concave disk and the soil, where oscillations of an operating element on a spring shank with a certain amplitude and frequency create a feedback in the system “soil – disk – spring shank”, has been suggested. A mathematical model has been developed and a theoretical investigation on the change in the drag forces of a disk operating element on a spring shank has been conducted. The dynamic characteristics of a spring shank in the course of unit operation have been determined within the range of the rigidity variation limits from 20 kN/m to 40 kN/m, the reduced mass limits from 100 N to 300 N, the draft force variation limits from 200 N дo 2000 N.

Achieving the ultra-high vacuum (UHV) in the collider and booster of the NICA project is one of the main challenges when creating this device. It determines the need for a serious approach to this issue and conducting research in this direction. First, it is necessary to understand the effect of the various components of the vacuum systems on the degree of vacuum. It is also necessary to carry out studies of pumping devices for producing the required vacuum (10–9 Pa) in the beam chamber and choose the most optimal pumping scheme. At the same time, it is necessary to figure out how various operations are carried out with the vacuum chamber: preparation of vacuum surfaces, letting in the atmosphere, and warming the chamber after closing the influence on the degree of vacuum and the composition of the residual gas. The temperature may vary from room temperature to liquid helium temperature due to the difficulty of keeping the beam-chamber walls at a constant temperature, including the inner components. This complicates the processes taking place within it. Additional complexity arises due the heating of the chamber walls by various processes during the operation of the accelerator (for example, cycling the magnetic field).

The NICA project, which includes several accelerators of charged particles, is under construction in the Laboratory of High Energy Physics, Joint Institute for Nuclear Research (JINR), Dubna. Obtaining the required vacuum conditions is one of the key points in implementing the project, because reaching the required ion lifetime at all stages of particle acceleration is what determines the effective luminosity of the experiments in the long run. Currently, modernization of the vacuum system of the injection complex of the LU-20 linear accelerator of light ions, one of oldest accelerators in the JINR, is being carried out and the new HILAC linear accelerator for the acceleration of gold ions in the collider mode of the NICA complex is being installed. At the end parts of the linear accelerators, the residual gas pressure must be approximately 10–5 Pa, which is determined by the maximum amplitude of the RF electric field used for the acceleration of ions.

Summary Loss of proteostasis is a fundamental process driving aging. Proteostasis is affected by the accuracy of translation, yet the physiological consequence of having fewer protein synthesis errors during multi-cellular organismal aging is poorly understood. Our phylogenetic analysis of RPS23, a key protein in the ribosomal decoding center, uncovered a lysine residue almost universally conserved across all domains of life, which is replaced by an arginine in a small number of hyperthermophilic archaea. When introduced into eukaryotic RPS23 homologs, this mutation leads to accurate translation, as well as heat shock resistance and longer life, in yeast, worms, and flies. Furthermore, we show that anti-aging drugs such as rapamycin, Torin1, and trametinib reduce translation errors, and that rapamycin extends further organismal longevity in RPS23 hyperaccuracy mutants. This implies a unified mode of action for diverse pharmacological anti-aging therapies. These findings pave the way for identifying novel translation accuracy interventions to improve aging., Graphical abstract, Highlights • Evolutionarily selected arginine in RPS23 is present only in hyperthermophilic archaea • RPS23 K60R mutation in flies leads to improved accuracy of protein synthesis with age • Yeast, worm, and fly RPS23 K60R mutants are longer-lived, healthier, and heat resistant • Anti-aging drugs, rapamycin, torin1, and trametinib, increase translation accuracy, Martinez-Miguel et al. demonstrate that improving translation fidelity by mutating a single amino acid in the decoding center of the ribosome suffices to improve health and longevity in yeast, worms, and flies. This work provides a direct link between fewer errors in translation and longevity.

The results of experimental studies are presented in article. It is established that minimal total costs for ensuring the technical preparedness of forage harvesters combines are possible to create using the optimal number of service activities. Formation of suboptimal number of service activities results in 27% and 18% losses (1 and 7 years of operational term of forage harvester). The article considers the graph of state of technical preparedness of forage harvester combines and develops an algorithm that calculates for each year of operation and for annual operating time the following indicators: average queue length; average number of pending requests; average number of service free channels; queue idle ratio; order utilization rate; idle ratio of servicing units; complete average losses due to idle queue requirements and less channel workload; time of waiting in line. The optimum number of channels was assumed to be the number with minimal total average cost of simple queuing requirements and no channel workload. The authors found out that the cost of ensuring of technical preparedness of forage harvesters depends on year of operation of harvesters and their annual loading. These costs reduce from 13.63% to 3.12%, for the accumulation of 150-180 hectares and from 6.5% to 3.98% (181-220 hectares). Therefore, with the increasing number of harvesters and their annual loading, the change in total costs is almost offset. The fluctuations in the total costs, depending on annual operating time and service assimilation of forage harvester, are less – 13.62% (150-180 ha) and 6.5% (221-330 ha).

We consider electric arc, electroslag welding with a consumable electrode, as well as other types of welding (gas, plasma, etc.) using rod filler materials. Two schemes of the corresponding type of welding are distinguished - the first, when an electrode has a finite length, the location of the current lead relative to it is stationary. In the second case, the electrode moves relative to the place of current supply in such a way that the length of the part of the electrode from its end to the place of current supply during welding varies little. A number of assumptions are made, a mathematical description of the heating and melting of the electrodes, filler materials due to the heat of the welding sources, and ohmic resistance is presented. Relations are given for estimating the temperature distribution along the length of an electrode, filler rods, and their melting rate.

The technical condition of parts is determined, on the one hand, by design parameters, and on the other, by mechanical properties, which are determined by control methods, including holographic ones. The properties of the working surfaces of parts made of various materials differ in comparatively small values of the dispersion of indicators. They correspond to the magnitudes and types of load, micro straining, load duration and can be presented in a rather narrow dispersion interval. The value of the distribution parameters of these quantities must be taken into account, first of all, when choosing a material. It is determined by the reliability conditions that the onset of the permissible load limit is achieved by proportional loading of the entire structure and is achieved with a micro deformation value for cultivator blades of 2.1-3.2μm. The limiting value of the micro deformation parameter is a function of a given tolerance for permanent deformation of the structure and is difficult to determine by conventional methods. In accordance with the developed methodology for the study of parts made of different materials, for example: graycastiron, aluminum, polymers (polyethylene, polyamide), carbon fiber, as well as a reinforced metal polymer, at the same time, computer holograms are recorded in each case. The studies used the entire range of recorded loads.

The structural properties of syntactic carbon foams made using different process approaches were studied by scanning electron microscopy. The paper shows that foam technology has a major influence on the formation of the foam structure.

The paper shows the influence of the composition and synthesis technology on the structure of syntactic carbon foams. It studies the foam technologies using carbon microballoons and phenol formaldehyde resin, and pitch carbonization under pressure. It reveals the influence of added mesophase microballoons in the starting pitch on the formation of a porous structure of syntactic carbon foams. It shows the macropore size distribution in carbon foams made by industrial carbonization under pressure.

This paper discusses the use of epoxy coatings modified with rice husk ash in order to reduce abrasive wear of materials and increase their durability during operation. It was experimentally established that the rice husk ash used as a filler increases the wear resistance and hardness of epoxy coatings with a significant decrease in the coefficient of static friction. This effect occurs when using ash obtained by burning rice husk at various temperatures. It is associated with an increase in the density of the formed spatial network in the presence of the studied filler, due to the selective sorption of the components of the epoxy composition by a developed solid surface.

The authors propose an approach for predicting the level of crops weediness with wild oats (Avena fatua L.), based on the implementation of Bayesian Belief Network. This approach is applicable for solving the problem of estimated growth and development probability of wild oat based on taking into account the prevailing conditions on a specific land plot in the current year, depending on the predecessor’s cultivation technology and weed seed stock. In the course of the work, the authors carried out a selection of factors affecting the level of wild oats weediness, they also identified the need to minimize the number of input parameters to achieve acceptable prediction accuracy. The proposed model allows calculating the probability of exceeding the economic threshold of harmfulness of wild oat in cultivated plants crops. The advantage of this approach and its versatility lies in the ability of Bayesian Belief Network to “discourse” with incomplete information and in the ability to include new information in the analysis.

The structure and properties of materials and working surfaces of needle holders were studied to improve the technology of their manufacture according to the characteristics of hardness and functionality of a microsurgical instrument. The types and modes of volumetric and surface hardening of VT6 titanium alloy (Ti-6Al-4V) using laser technologies adapted to the working surfaces of the tool are proposed. The possibility of using the alloy to replace maraging steel in the manufacture of needle holders is evaluated

When combine harvesters work, about half of the engine power is spent on extracting grain from ears of grain crops. The high energy costs for extracting grain from ears are due to the need to drag straw through a threshing device, the small displacement between the drum or rotor and deck, as well as to extract grain from ears of grain crops mainly by impact. Upon impact, grain damage also occurs. Therefore, the task was to develop a combine harvester that extracts grains from the ears of grain crops by grinding. For modeling, the assumption was made that the spike fell on the deck, after which it was clamped between the working branch of the conveyor and the deck strictly perpendicular to the direction of movement of the conveyor branch. The conveyor belt moves uniformly, and the deck oscillates. The movement of the conveyor and deck from the initial position is considered in the opposite direction. To efficiently removesingle grains from the ears, when the conveyor belt and deck are moved in opposite directions, it must rotate 360°. As a result of the simulation, the kinematic parameters of the process were detected during the opposite movement of the conveyor and deck. The following are determined: the speed of the belt of the upper conveyor, the angular speed of the drive shaft of the upper conveyor, the period of oscillation of the deck, the movement and the angle of rotation of the ear located between the working branch of the conveyor and the deck, when they are counter-moving. The simulation will then allow us to consider the movement of the ear during the movement of the conveyor and deck from the starting position and, based on the calculations, to identify the structural and kinematic parameters of the conveyor and deck.

The questions of applying on the working surfaces of the sliding friction units of babbitt coatings by gas-flame spraying are considered. The operating conditions of babbit bearings are discussed, the main causes and types of their destruction are determined. The widely used technologies for applying babbitt coatings with the method of flame spraying are compared. Experimentally, using the methods of mechanical tests, qualitative and quantitative analysis of the metal structure in control samples, the influence of the main operating parameters of the deposition on the porosity of the babbit coating material, its adhesion to the substrate, wear resistance, and other performance indicators are studied. Rational sputtering distance, the temperature of heating the surface of the substrate before sputtering are established, which ensure optimal values of these indicators. As a result of the analysis of the experimental data, regression relations were obtained characterizing the dependences of the adhesion strength, wear resistance on design (coating thickness), technological (spraying distance), and operational (load, sliding speed) factors.

Sexual reproduction which involves alternation of meiosis and syngamy is the ancestral condition of extant eukaryotes. Transitions to asexual reproduction were numerous, but most of the resulting eukaryotic lineages are rather short-lived. Still, there are several exceptions to this rule including darwinulid ostracods1,2and timema stick insects3. The most striking of them is bdelloid rotifers4–6, microscopic freshwater invertebrates which underwent an extensive adaptive radiation after apparently losing meiosis over 10 Mya. Indeed, both the lack of males in numerous bdelloid species and the lack of proper homology between chromosomes6rule out ordinary sex. However, this does not exclude the possibility of some other mode of interindividual genetic exchange and recombination in their populations7. Recent analyses based on a few loci suggested genetic exchanges in this group8,9, although this has been controversial10. Here, we compare complete genomes of 11 individuals from the wild population of the bdelloid rotiferAdineta vaga,and show that its genetic structure, which involves Hardy-Weinberg proportions of genotypes within loci and lack of linkage disequilibrium between distant loci, is incompatible with strictly clonal reproduction. Instead, it can emerge only under ongoing recombination between different individuals within this species, possibly through transformation. Such a genetic structure makes the population immune to negative long-term consequences of the loss of conventional meiosis11, although this does not necessarily imply that interindividual genetic exchanges inA. vagaare directly maintained by natural selection.

A long-standing belief is that aging (senescence) is the result of stochastic damage accumulation. Alternatively, senescent pathology may also result from late-life, wild-type gene action (i.e., antagonistic pleiotropy, as argued by Williams) leading to non-adaptive run-on of developmental programs (or quasi-programs) (as suggested more recently by Blagosklonny). In this study, we use existing and new data to show how uterine tumors, a prominent form of senescent pathology in the nematode Caenorhabditis elegans, likely result from quasi-programs. Such tumors develop from unfertilized oocytes which enter the uterus and become hypertrophic and replete with endoreduplicated chromatin masses. Tumor formation begins with ovulation of unfertilized oocytes immediately after exhaustion of sperm stocks. We show that the timing of this transition between program and quasi-program (i.e., the onset of senescence), and the onset of tumor formation, depends upon the timing of sperm depletion. We identify homology between uterine tumors and mammalian ovarian teratomas, which both develop from oocytes that fail to mature after meiosis I. In teratomas, futile activation of developmental programs leads to the formation of differentiated structures within the tumor. We report that older uterine tumors express markers of later embryogenesis, consistent with teratoma-like activation of developmental programs. We also present evidence of coupling of distal gonad atrophy to oocyte hypertrophy. This study shows how the Williams Blagosklonny model can provide a mechanistic explanation of this component of C. elegans aging. It also suggests etiological similarity between teratoma and some forms of senescent pathology, insofar as both are caused by quasi-programs.

Daphniareproduce by cyclic-parthenogenesis, where phases of asexual reproduction are intermitted by sexual production of diapause stages. This life cycle, together with environmental sex determination, allow the comparison of gene expression between genetically identical males and females. We investigated gene expression differences between males and females in four genotypes ofDaphnia magnaand compared the results with published data on sex-biased gene expression in two otherDaphniaspecies, each representing one of the major phylogenetic clades within the genus. We found that 42% of all annotated genes showed sex-biased expression inD. magna. This proportion is similar both to estimates from otherDaphniaspecies as well as from species with genetic sex determination, suggesting that sex-biased expression is not reduced under environmental sex determination. Among 7453 single copy, one-to-one orthologs in the threeDaphniaspecies, 707 consistently showed sex-biased expression and 675 were biased in the same direction in all three species. Hence these genes represent a core-set of genes with consistent sex-differential expression in the genus. A functional analysis identified that several of them are involved in known sex determination pathways. Moreover, 75% were overexpressed in females rather than males, a pattern that appears to be a general feature of sex-biased gene expression inDaphnia.Short summaryIn some species with environmental sex determination, gene expression can be compared between genetically identical males and females. Here, we investigated sex-biased expression in one such species,D. magna, and compared it with data from two congeners. We found that all three species have a common set of 675 genes with consistent differential expression and with a strong bias towards overexpression in females rather than males. Moreover, the proportion of sex-biased genes in each of the threeDaphniaspecies was similar toDrosophilaspecies with genetic sex determination, suggesting that sex-biased expression is not necessarily reduced under environmental sex determination.

A long-standing belief is that aging (senescence) is the result of stochastic damage accumulation. Alternatively, senescent pathology may also result from late-life, wild-type gene action (i.e., antagonistic pleiotropy, as argued by Williams) leading to non-adaptive run-on of developmental programs (or

Summary Organismal death is a process of systemic collapse whose mechanisms are less well understood than those of cell death. We previously reported that death in C. elegans is accompanied by a calcium-propagated wave of intestinal necrosis, marked by a wave of blue autofluorescence (death fluorescence). Here, we describe another feature of organismal death, a wave of body wall muscle contraction, or death contraction (DC). This phenomenon is accompanied by a wave of intramuscular Ca2+ release and, subsequently, of intestinal necrosis. Correlation of directions of the DC and intestinal necrosis waves implies coupling of these death processes. Long-lived insulin/IGF-1-signaling mutants show reduced DC and delayed intestinal necrosis, suggesting possible resistance to organismal death. DC resembles mammalian rigor mortis, a postmortem necrosis-related process in which Ca2+ influx promotes muscle hyper-contraction. In contrast to mammals, DC is an early rather than a late event in C. elegans organismal death. Video Abstract, Graphical Abstract, Highlights • A wave of body wall muscle contraction occurs during C. elegans organismal death • This rigor mortis-like phenomenon is coupled to a wave of intestinal necrosis • Both waves are accompanied by Ca2+ release and a drop in ATP levels • Properties of long-lived daf-2 mutants suggest resistance to organismal death, Galimov et al. describe mechanisms of organismal death in C. elegans. They document a rigor mortis-like wave of muscle hyper-contraction accompanied by Ca2+ release and falling ATP, which is coupled to the previously described wave of intestinal necrosis in a process that resembles a distorted and deadly defecation cycle.

The comparative analysis of a combination of primary properties of foam materials made using the different starting components and technologies was made. According to the review of the literature and analysis of the experimental data, the paper shows a significant influence the starting components and process approaches have on the properties of the materials. The comparison of material properties revealed that the properties of syntactic carbon foams are higher than those of other porous materials, including metal foams, and comply with the specification.

The paper studied the influence of starting components and operating conditions of synthesis processes on the performance properties of syntactic carbon foams. The studies determined the behavior and ranges of hardness, ultimate compressive strength, apparent density, and thermal conductivity of foams made by template carbonization and using carbon microballoons, depending on heat treatment temperature. They determined the influence of a volatile blowing agent (sodium chloride) with wide and narrow fraction on a change in the studied properties of syntactic carbon foams.

NICA is a new accelerator collider complex under construction at JINR. The facility is aimed at providing collider experiments with heavy ions up to Uranium in a center of mass energy range from 4 to 11 GeV/u and an average luminosity up to 1027 cm -2 s-1. The collisions of polarized deuterons are also foreseen. The facility includes two injector chains, a new superconducting booster synchrotron, the existing 6 AGeV superconducting synchrotron Nuclotron, and a new superconducting collider consisting of two rings, each of about 500 m in circumference. The booster synchrotron and the NICA collider are based on an iron-dominated “window frame”-type magnet with a hollow superconductor winding analogous to the Nuclotron magnet. The status of the development of the full size model magnets for the booster synchrotron as well as for the NICA collider is presented. The test results of model magnets are discussed. The status of the creation of a facility for serial tests of superconducting magnets for the NICA project is described.

Актуальность темы определяется широким развитием и применением мобильных вычислительных средств, использующихся для хранения и обработки конфиденциальных информационных ресурсов. Данная работа посвящена вопросам защиты информационных ресурсов в бортовой системе транспортных средств от несанкционированного доступа. Выявлены недостатки существующих подходов защиты подобных систем вследствие широких возможностей злоумышленников вне контролируемых зон воздействия как на средства защиты, так и на пользователей системы. В связи с этим предложен подход защиты информационных ресурсов мобильных вычислительных средств, позволяющий получить доступ только в защищенных зонах. В статье разработана структурная модель многоуровневой системы защиты доступа к информационному ресурсу, включающая следующие уровни: физическую защиту, систему аутентификации, криптографическую и стеганографическую системы. Особенность данного метода заключается в том, что предлагается дополнить правила доступа к ресурсу данных подсистем контролем местоположения мобильного объекта информатизации. Это достигается за счет формирования ключей криптографической и стеганографической систем с учетом данных о географических координатах мобильного объекта. На основе данной модели разработано программное средство для защиты доступа к информационному ресурсу с учетом навигационного ключа, позволяющее повысить уровень защищенности мобильных объектов информатизации.

An alloy of cast pipes produced in the Russian Federation and a welding method for restoring coil sections made of imported pipes damaged by gas corrosion in pyrolysis furnaces are proposed. Substantiation of the alloy choice is carried out according to the research results of composition and structure of the metal of the original pipes and according to the criteria of structural strength using a proven diagram of controlled damageability. Recommendations for optimizing the composition, microalloying, and structure of the proposed alloy of thick-walled cast pipes for the elimination of the deficiencies identified by the research are presented. The alloy advantages by mechanical properties in the temperature range up to 800…890°C are shown on samples of an experimental cast pipe.

Technology for producing syntactic carbon foams by the method of pitches carbonization under pressure is proposed. The components and optimal regime parameters for producing the foams with given thermophysical and strength characteristics are determined. The foams structure was studied using scanning electron microscopy.

Technology for producing the articles based on the syntactic carbon foams is proposed. Components and regime parameters for producing the foams of open-porous cellular structure with specified thermophysical and strength characteristics are determined.

The structural strength properties determined by the true stress-deformation diagram and the fatigue characteristics of materials at combined action (tension and bending) under the conditions of temperature change are used to substantiate materials and technologies. The domestic alloy is suggested as an alternative to imported heat-resistant alloy IN-738LC used to manufacture the turbine rotor blades of stationary gas turbine plants (GTP). Expressions to determine the fatigue characteristics according to the criteria of structure stability are presented.

Ways to use gabbro-basalt raw material for the production of mineral wool and industry’s demand for it are examined. The reasons for quality and composition variations of the raw material are shown. Recommendations for solving the raw material problem are made for producers — preparation of domestic deposits based on geological prerequisites, mineral-technological mapping of objects and organization of selective raw materials production.

Sex chromosomes can evolve during the evolution of genetic sex determination (GSD) from environmental sex determination (ESD). Despite theoretical attention, early mechanisms involved in the transition from ESD to GSD have yet to be studied in nature. No mixed ESD-GSD animal species have been reported, except for some species ofDaphnia, small freshwater crustaceans in which sex is usually determined solely by the environment, but in which a dominant female sex-determining locus is present in some populations. This locus follows Mendelian single-locus inheritance, but has otherwise not been characterized genetically. We now show that the sex-determining genomic region maps to the same low-recombining peri-centromeric region of linkage group 3 (LG3) in three highly divergent populations ofD. magna, and spans 3.6 Mb. Despite low levels of recombination, the associated region contains signs of historical recombination, suggesting a role for selection acting on several genes thereby maintaining linkage disequilibrium among the 36 associated SNPs. The region carries numerous genes involved in sex differentiation in other taxa, includingtransformer2andsox9. Taken together, the region determining the NMP phenotype shows characteristics of a sex-related supergene, suggesting that LG3 is potentially an incipient W chromosome despite the lack of significant additional restriction of recombination between Z and W. The occurrence of the female-determining locus in a pre-existing low recombining region illustrates one possible form of recombination suppression in sex chromosomes.D. magnais a promising model for studying the evolutionary transitions from ESD to GSD and early sex chromosome evolution.

P66shc protein is an alternative transcript product of the SHC1 gene. Whereas two other isoforms (p52shc and p46shc) have adaptor function in the RAS signaling pathway, p66shc regulates the amount of reactive oxygen species (ROS) in a cell. Previously, it was demonstrated that the p66shc genome knockout significantly extends maximal lifespan in mice. P66shc could translocate into the mitochondria and increase intracellular ROS level, although basic mechanisms of this activity remain poorly understood. P66shc seems to play a significant role in carcinogenesis since an increased expression of p66shc correlates with poor prognosis in colorectal carcinoma. In our study, we applied RNA interference using lentiviral constructions that express short hairpin RNA (shRNA) against the N-terminal CH2 domain of the p66shc isoform. As a consequence, the p66shc but not p52shc and p46shc isoforms was selectelively suppressed in the RKO colon carcinoma cell line. We found that RKO cells with p66shc knockdown have been shown to be more resistant to oxidative stress induced by hydrogen peroxide exposure or serum starvation. Moreover, mitochondrial fragmentation that depends on the mitochondrial ROS amount was significantly decreased in p66shc-deficient RKO cells. Our findings are consistent with the hypothesis that p66shc participates in mitochondrial accumulation of ROS during oxidative stress and consequently promotes induction of apoptosis.

In Daphnia (Cladocera, Crustacea), parthenogenetic reproduction alternates with sexual reproduction. Individuals of both sexes that belong to the same parthenogenetic line are genetically identical, and their sex is determined by the environment. Previously, non-male producing (NMP) genotypes have been described in species of the Daphnia pulex group. Such genotypes can only persist through phases of sexual reproduction if they co-occur with normal (MP) genotypes that produce both males and females, and thus the breeding system polymorphism is similar to gynodioecy (coexistence of females with hermaphrodites), which is well known in plants. Here we show that the same breeding system polymorphism also occurs in Daphnia magna, a species that has diverged from D. pulex more than 100 MY ago. Depending on the population, between 0% and 40% of D. magna females do not produce males when experimentally exposed to a concentration of the putative sex hormone methyl farnesoate that normally leads to male-only clutches. Natural broods of these NMP females never contained males, contrasting with high proportions of male offspring in MP females from the same populations. The results from a series of crossing experiments suggest that NMP is determined by a dominant allele at a single nuclear locus (or a several closely linked loci): NMP × MP crosses always yielded 50% NMP and 50% MP offspring, whereas MP × MP crosses always yielded 100% MP offspring. Based on cytochrome c oxidase subunit I-sequences, we found that NMP genotypes from different populations belong to three highly divergent mitochondrial lineages, potentially representing three independent evolutionary origins of NMP in D. magna. Thus, the evolution of NMP genotypes in cyclical parthenogens may be more common than previously thought. Moreover, MP genotypes that coexist with NMP genotypes may have responded to the presence of the latter by partially specializing on male production. Hence, these populations of D. magna may be a model for an evolutionary transition from a purely environmental to a partially genetic sex determination system.

Предложена модель выбора базовых функций при автоматизированной идентификации временных рядов, алгоритм и программное средство идентификации временных рядов на основе ассоциативно-мажоритарного подхода, позволяющие идентифицировать вид базовых зависимостей динамических процессов. Задача идентификации вида базовых функций решается с использованием классической теории распознавания образов. Идентификация производится путем сравнения исходного образа с эталонами, хранящимися в едином пространстве образов. Пространство образов представляет собой область памяти устройства (ассоциативной памяти), на котором производится идентификация. Особенностью предложенной модели является оперативность сравнения исходных образов с образами эталонов за счет использования единого признакового пространства и возможности сравнения всех образов за один такт. Для повышения оперативности идентификации в алгоритме выбора базовых функций также использован ассоциативно-мажоритарный подход к хранению и поиску идентификационных данных в электронной памяти. Предложенный алгоритм и программное средство выбора базовых функций являются универсальными, так как позволяют идентифицировать вид базовой зависимости в любом динамическом процессе независимо от специфики исследуемой предметной области. Автоматизированная идентификация вида базовых функций сокращает время построения прогнозных моделей и позволяет оперативно прогнозировать дальнейшие варианты протекания процесса.

Technologies for producing two classes of syntactic carbon foams of regular structure were developed: thermal insulating and heat-conducting foams with specific physico-mechanical properties designed for operation under extreme conditions. The possibility of controlled development of porous structure in carbon foams upon their production by selecting the initial components in the form of binders, hollow particles (microspheres) and various additives (solvents, etc.), their optimal combination and ratio, as well as operating parameters of thermal processing. Phenol-formaldehyde resins, melamine and coal or oil pitches filled with hollow particles in the form of phenolic and carbon microspheres were used as starting components for the production of carbon foams. Technologies for producing carbon foams include the sequence of the following stages: preparation and mixing of the starting components, molding of samples, carbonization, graphitization, pyrocompaction and mechanical processing. Thermal insulation foams were obtained using two technologies. The first technology for producing foams involves using phenolic microspheres and a binder in the form of a phenol-formaldehyde resin of the novolac type. The second technology for producing foams through template carbonization involves the use of high porosity melamine with cellular structure as a binder, and hollow phenolic microspheres.

In the Laboratory of High Energies at the Joint Institute for Nuclear Research, as part of the NICA-MPD [1] project, tests of two prototypes of HTSC current leads prepared at ASIPP institute (Hefei, China) have been performed [2, 3] to measure electric and heat parameters and to search for structural and physical drawbacks. Based on the experimental results, necessary changes are made in the structure of HTSC current leads of the testing stand for the magnetic element testing of the NICA accelerating complex and its basic setups: the Nuclotron, Booster, and Collider.

This review covers current concepts of immune and genetic mechanisms of infertility associated with human urogenital chlamydial infection. It describes studies of individual polymorphisms of genes coding cytokines and other immune system mediators. It also presents the results of studies aimed at searching for genetic predisposition to the development of complications resulting in human reproductive function disorders caused by past urogenital chlamydial infections.

The relevance of the topic is determined by the widespread development of distributed video surveillance systems characterized by a large number of video cameras and located on a large territory. The efficiency of distributed video surveillance systems depends on a variety of factors, such as the recognition algorithms used, the technical characteristics of cameras and data processing facilities. Also, the quality of the video surveillance system largely depends on the topology of the placement of video cameras. The objective function minimizes the number of cameras while providing the required level of veracity of event recognition. It is believed that the quality of recognition mainly depends on the spatial resolution of the recognized object on the video frame. This parameter is determined by the technical characteristics of the camera and the distance to the recognized object. When crossing the field of view of several cameras and the possibility of combining their results increases an estimation of veracity of object recognition. Thus, when locating cameras in a controlled area, it is necessary to take into account a number of parameters: coordinates, viewing angles, areas of intersection of the field of view of cameras. This problem is characterized by high computational complexity. Therefore, to obtain the result for an acceptable time, an algorithm for optimizing the topology based on the method of swarm particles is proposed. The presented approach to optimize camera placement topology will reduce the time of designing a video surveillance system.

Species with a large geographic distributions present a challenge for phylogeographic studies due to logistic difficulties of obtaining adequate sampling. For instance, in most species with a Holarctic distribution, the majority of studies has concentrated on the European or North American part of the distribution, with the Eastern Palearctic region being notably understudied. Here, we study the phylogeography of the freshwater cladoceran Daphnia magna Straus, 1820 (Crustacea: Cladocera), based on partial mitochondrial COI sequences and using specimens from populations spread longitudinally from westernmost Europe to easternmost Asia, with many samples from previously strongly understudied regions in Siberia and Eastern Asia. The results confirm the previously suspected deep split between Eastern and Western mitochondrial haplotype super-clades. We find a narrow contact zone between these two super-clades in the eastern part of Western Siberia, with proven co-occurrence in a single lake in the Novosibirsk region. However, at present there is no evidence suggesting that the two mitochondrial super-clades represent cryptic species. Rather, they may be explained by secondary contact after expansion from different refugia. Interestingly, Central Siberia has previously been found to be an important contact zone also in other cladoceran species, and may thus be a crucial area for understanding the Eurasian phylogeography of freshwater invertebrates. Together, our study provides an unprecedented complete, while still not global, picture of the phylogeography of this important model species.

The molecular organization, copy number, and chromosome location of the human TNF/LT transgenes were studied in the genomes of two transgenic mouse strains. One strain proved to carry two transgene copies arranged head-to-tail and detected on chromosome 8 by karyotyping. The other strain had one transgene copy observed on chromosome 5. The strains provide a model for studying the physiological functions of the tumor necrosis factor and lymphotoxin.

The long 5′-untranslated region (5′-UTR) of the human L1 retrotransposon contains a unique internal promoter, allowing new L1 copies to be less dependent on the integration site at the transcriptional level. The mechanism of action of this promoter still remains unclear; however, some early studies have build up an opinion that the first 5′-UTR segment of 100–150 nt (known as the minimal promoter) is most crucial for the functioning of the full-length promoter. This study shows that the activity of the minimal promoter is rather low in comparison with the activity of the full-length 5′-UTR. Instead, 5′-UTR internal segment 390–662, containing numerous binding sites for various transcription factors, is indispensable for effective L1 transcription and can be considered as a transcriptional enhancer. Deletion of this segment dramatically reduces the level of transcription irrespective of the cell type, whereas deletion of the first 100 nt decreases the transcription level only by a factor of 1.5–2. Thus, the L1 regulatory region remains to be structurally similar to that of well-studied invertebrate LINEs. It is also possible that the internal 5′-UTR segment of L1 contains an alternative promoter, driving synthesis of a 5′-truncated L1 mRNA.