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The first ichthyosaurian specimens discovered from the Upper Triassic of the Russian Arctic (Kotelny Island, New Siberian Islands) are described herein. They include the remains of large- to small-bodied ichthyosaurians originating from six stratigraphic levels spanning the lower Carnian to middle Norian. The material is mostly represented by isolated vertebrae and ribs, which are not possible to accurately diagnose, but also includes specimens comprising associated vertebrae and a fragmentary skeleton that preserves cranial remains (parabasisphenoid, fragmentary quadrate, partial mandible and hyoids). Based on vertebral and rib morphology, we identify the specimens as representatives of the following taxonomic groups: large-bodied shastasaurids, medium-sized indeterminate ichthyosaurians with a single rib facet in the presacral centra, and small euichthyosaurians with double rib facets present throughout the presacral vertebrae that likely represent toretocnemids and/or basal parvipelvians. In addition, the cranial and mandibular remains preserved in one of the specimens, ZIN PH 5/250, were studied using micro-computed tomography. Its mandible is highly similar to that of toretocnemids, whereas the parabasisphenoid demonstrates a peculiar combination of both plesiomorphic and derived character states, providing the first detailed data on this cranial element in a Late Triassic ichthyosaurian. Furthermore, the specimen also demonstrates a distinctive condition of rib articulation in the anteriormost presacral (cervical) vertebrae, which together with other features allows for the erection of a new taxon – Auroroborealia incognita gen. et sp. nov. Although the phylogenetic position of this taxon is uncertain due to its fragmentary nature, its anatomy, indicating toretocnemid or parvipelvian affinities, further supports the previously hypothesised sister-group relationships between these two clades. The morphology of the parabasisphenoid and vertebral column of the new taxon is discussed in broader contexts of the patterns of evolution of these skeletal regions in ichthyosaurs.

The article describes the problems and perspective of introduction of distance learning at various levels of education. The technologies of distance learning are presented

The article describes the teachers and students’ pandemic causes of stress during distance learning. The methods of increasing stress resistance are considered.

Marine reptile occurrences are rare in the Lower Jurassic Series outside of Europe. Here we describe diverse marine reptile faunas from the Lower Jurassic Series (Pliensbachian and Toarcian stages, including the Toarcian–Aalenian boundary interval) of Eastern Siberia. The taxonomic composition of Toarcian marine reptile assemblages of Siberia highlight their cosmopolitan nature, with the presence of taxa previously known nearly exclusively from coeval strata of Europe, such as ichthyosaurians Temnodontosaurus and Stenopterygius, microcleidid plesiosaurians (including the genus Microcleidus), rhomaleosaurids and basal pliosaurids. The palaeogeographic reconstruction places these faunas to the palaeopolar region, north of the 80th northern parallel and up to the palaeo north pole (upper value within the 95% confidence interval for some of the localities). The materials include remains of both mature and juvenile (or even infant, judging by their very small size and poor ossification) animals, indicating a possibility that these polar seas may serve as a breeding area. The diversity and abundance of plesiosaurians and ichthyosaurians, along with a lack of thalattosuchian remains (considering their wide distribution elsewhere at low latitudes), is an additional argument that plesiosaurians and neoichthyosaurians were able to live and reproduce in a polar environment. There is no certainty whether these animals lived in polar seas permanently, or whether they were taking seasonal migrations. However, given the polar night conditions at high latitudes, the latter seems more plausible, and both these scenarios are further indirect evidence that these groups likely had a high metabolism.

The analysis of existing geodesic methods of deformation monitoring of hydraulic structures is carriedent. The conclusion about the most effective methods, and the ways of further research are outlined is made.

Various software features such as classes, methods, requirements, and tests often have similar functionality. This can lead to emergence of duplicates in their descriptive documentation. Uncontrolled duplicates created via copy/paste hinder the process of documentation maintenance. Therefore, the task of duplicate detection in software documentation is of importance. Solving it makes planned reuse possible, as well as creating and using templates for unification and automatic generation of documentation. In this paper, we present an approach for interactive detection of near duplicates that involves the user in order to conduct meaningful search. It includes a new formal definition of a near duplicate, a pattern-based , and the proof of its completeness. Moreover, we demonstrate the results of experimenting on a collection of documents of several industrial projects.

Nowadays, the search for and development of new forms of materials with biocides is an actual problem of the modern science of nanosized materials due to the problem of microbiological contamination, which can be solved by using nanocontainers carrying biocides. Depending on the morphology of the nanocontainers and the filled active agents, it is possible to create coatings with specially designed self-healing functionality or multifunctional properties. The purpose of this work was to produce submicro-containers (SMCs) with a shell of SiO2 nanoparticles and a core of polymerized 3- (trimethoxysilyl) propyl methacrylate filled with 5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT) in an oil in water (O/W) emulsion. The chemical nature of the individual components of the system and nano-capsules were investigated using NMR spectroscopy. The size and zeta potential of the SMCs were measured by a dynamic light scattering method (d = 170&ndash, 180 nm, polydispersity index PDI = 0.125 and zeta-potential = 55 mV), the morphology of their outer surface was determined using SEM. The results of NMR analysis showed that during the addition of the biocide into the SMCs, its chemical structure is retained, as is its activity. Minor changes in the chemical shifts of the 1H NMR spectra of the SMCs with DCOIT, as well as of the biocide itself, confirm the inclusion of DCOIT inside the SMCs.

We carried out comparative study of the effect of inhibitor-loaded nanocontainers on corrosion protection performance of polyepoxy powder coatings employing neutral salt-spray test (5% NaCl, 35 °C, different time). We demonstrated that halloysites and mesoporous silica particles loaded with corrosion inhibitor 8-hydroxyquinoline can be homogeneously distributed in powder coating effectively reducing corrosion of the metal substrate over 1000 h of salt-spray test. Addition of only 2 wt.% of inhibitor encapsulated in both nanocontainers to the powder coating is sufficient to decrease the delamination effect by 2–3 times and suppress the formation of the pitting corrosion.

In current times, trading success depends on choosing a correct strategy. Algorithmic trading is often based on technical analysis — an approach where the values of one or several technical indicators are translated into buy or sell signals. Thus, every trader's main challenge is the choice and use of the most fitting trading rules. In our work, we suggest an evolutionary algorithm for generating and selecting the most fitting trading rules for interday trading, which are presented in the form of binary decision trees. A distinctive feature of this approach is the interpretation of the evaluation of the current state of technical indicators with the help of dynamic ranges that are recalculated on a daily basis. This allows to create long-term trading rules. We demonstrate the effectiveness of this system for the Top-5 stocks of the United States IT sector and discuss the ways to improve it.

From the northern part of Chukotka Region (Russian Far East) and Nether-Polar Urals, one of the oldest and one of the most northerly occurrences of mosasaur remains in the world are recorded. The appearance of mosasaurs at high latitudes could be explained by the expansion of their habitat and an unusual balance of insolation. Polar day conditions could have been useful for marine predators such as mosasaurs because they could have hunted for prey at any time. During the Cretaceous, almost two months of complete darkness can be reconstructed for the territory of present-day Chukotka, and more than one month of twilight. It is highly unlikely that these large-sized animals with a high metabolic rate were capable of surviving in complete darkness. Seen in this light, mosasaur remains at both high and low latitudes can serve as indirect evidence of seasonal migrations.

This paper describes fragmentary turtle material (isolated basisphenoid, shell bones, humerus and ilium) from the Lower Cretaceous (Berriasian–Barremian) Teete locality in Yakutia (Eastern Siberia, Russia). All the material is attributed to one taxon of basal turtles (Mesochelydia indet.), based on the morphology of the basisphenoid, shell bones and humerus, as well as microanatomy and histology of the shell bones and humerus. Canals and foramina of the basisphenoid of this taxon revealed by CT scanning show an unusual pattern, which allows various interpretations and suggests a higher diversity of carotid and/or vidian systems in basal turtles than hitherto believed. Mesochelydia indet. from Teete fills an Early Cretaceous gap in the record of Asian basal turtles and represents the northernmost Asian non-marine turtle occurrence of the Mesozoic. All in all, the record of Asian basal turtles appears to be wider geographically and more complete temporally than previously thought. The Asian basal turtles are represented by at least three phylogenetic lineages: primitive Testudinata in the Late Triassic, primitive Mesochelydia from the Early Jurassic to the Early Cretaceous and primitive Perichelydia from the Middle Jurassic to the Late Cretaceous. The presence of such a primitive (Jurassic level) turtle in Teete supports the hypothesis that the vast territory of Siberia was a refugium for Jurassic vertebrate faunal elements. Details of the external morphology and histology of the Teete turtle material as well as its high paleolatitude occurrence argue in favor of its aquatic lifestyle.

A frontal of the mosasaur Clidastes propython from the Beloe Ozero locality in the Saratov Region (Rybushka Formation, Campanian Stage, Upper Cretaceous) is described. The investigated specimen differs from the frontals of other members of the genus Clidastes in the relatively straight lateral flanks. Reliable records of Clidastes outside America have previously been reported only from Great Britain, Sweden, and Germany. The new record from the Beloe Ozero locality expands the known geographical range of the species C. propython and genus Clidastes.

The synthesis and properties of submicrocontainers with a shell of nanoparticles of silicon dioxide and a core of polymerized 3-(Trimethoxysilyl) propyl methacrylate loaded with 5Dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT) are considered. The resulting containers were characterized by scanning electron microscopy SEM, laser correlation spectroscopy and thermogravimetric analysis. The obtained submicrocontainers show low polydispersity with a small increase in size in comparison with the initial droplet size of the Pickering emulsion. The Zeta potential of the final containers was sufficiently negative at pH7 to be stable. The maximum release of encapsulated biocide was observed over approximately 24–27 h with a lease of about 78% of the encapsulated biocide during 3.5 h. The effectiveness of the encapsulated biocide by the Pickering emulsion technique was studied by tests on the growth rate of a microfungi colony (Aspergillus niger, Aspergillus awamori) and the growth rate of the bacteria Bacillus cereus. The test shows that the submicrocontainers of DCOIT facilitate a growth inhibition of 70% against 52% for the free biocide after 5 days, this is due to the fact that free biocide loses its activity promptly, while the encapsulated biocide is released gradually, and thus retains its effectivity for a longer time.

Contemporary software documentation is as complicated as the software itself. During its lifecycle, the documentation accumulates a lot of “near duplicate” fragments, i.e. chunks of text that were copied from a single source and were later modified in different ways. Such near duplicates decrease documentation quality and thus hamper its further utilization. At the same time, they are hard to detect manually due to their fuzzy nature. In this paper we give a formal definition of near duplicates and present an algorithm for their detection in software documents. This algorithm is based on the exact software clone detection approach: the software clone detection tool Clone Miner was adapted to detect exact duplicates in documents. Then, our algorithm uses these exact duplicates to construct near ones. We evaluate the proposed algorithm using the documentation of 19 open source and commercial projects. Our evaluation is very comprehensive – it covers various documentation types: design and requirement specifications, programming guides and API documentation, user manuals. Overall, the evaluation shows that all kinds of software documentation contain a significant number of both exact and near duplicates. Next, we report on the performed manual analysis of the detected near duplicates for the Linux Kernel Documentation. We present both quantative and qualitative results of this analysis, demonstrate algorithm strengths and weaknesses, and discuss the benefits of duplicate management in software documents.

Polymer/surfactant mixtures have a wide range of industrial and technological applications, one of them being the use in microencapsulation and emulsion stabilization processes. These mixtures are able to form adsorption layers at the surface of oil droplets and so affect the emulsion stability, which depends on the polyelectrolyte/surfactant nature, concentrations ratio, method of the emulsification, etc. Polyelectrolytes alone show low surface activity in contrast to surfactants, which adsorb at the water/oil interface, making the droplets charged, but they are insufficient to stabilize emulsions. When an oppositely-charged polymer is added to the surfactant solution, a steric barrier is formed, which prevents coalescence and enhances the stability. The present review is devoted to the recent studies of the use of polymer/surfactant mixtures for the encapsulation of active ingredients and stabilization of single and double emulsions. Active ingredients are added to the oil phase prior to emulsification so that any subsequent dissolution of the core, like in other encapsulation protocols, can be omitted. By measuring the interfacial tension and dilational rheology it is possible to find optimum conditions for the emulsion formation and hence for encapsulation. Therefore, such systems have become a prominent approach for the encapsulation of active ingredients.

Chitosan/xanthan gum microcontainers with a core-shell structure formed due to chemical interactions between polysaccharide chains induced by ultrasonication are presented. Containers were prepared by sonication of water-immiscible (oil-like) liquids in the solution of polysaccharides. One-step fabrication of the container permanent shell is possible, because of the contribution of ultrasonically caused formation of hydrogen bonds and amide linkages. We synthesized containers in a wide size range from 350 nm to 7500 nm, varying in oil/water ratio. The microcontainers were modified with oppositely charged polyelectrolytes and microparticles, which could be used to impart the specified properties to the system. The biocide 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one (DCOIT) was loaded into the proposed containers by utilizing its solution as an oil phase. The following incorporation of the DCOIT containers into the polymer coating demonstrated more sustained antimicrobial activity (∼30%) of the biocide in the encapsulated state, compared to its non-encapsulated form.

The article analyzes the possibilities of education to overcome infantilism and consumer orientation of the younger generation. Even humanistic “pedagogy of relations” is being eroded in the consumer society. Nowadays, to talk about school and to build the school in which children feel only cozy, comfortable and convenient means to prepare new victims of consumerism. The authors state the need of moving from the usual methods and forms of education (formally ritualized, verbal, leisure and entertainment ones) to the creative, activity methods and forms, which cultivate the relationships of responsible care. The new institute of education, which is child-adult creating community, is justified both theoretically and practically. The authors provide the examples of mutually beneficial and developing cooperation of adults and children based on the principles of technology, self-management, social entrepreneurship and social service.

Territorial educational complexes, which combine the "strong" and "weak" schools, kindergartens, additional education institutions can not only provide real access to the quality education, but also reduce social contradictions and bring different layers of society together. However, to do it they should definitely not only be educational corporations, but the new institutions of socialization. It is unproductive to use traditional educational strategies of socialization which are the transfer of educational forms and learning content to the social life of the school or direct copying of social practices. Educational complexes need to implement the strategy of adaptation to the unknown, to take the initiative for positive change in the close society. There are certain preconditions to it in the complexes, such as consolidation of family potential, concentration of resources and their efficient use, openness to new technologies and management systems, transformation of education to the public good for the population. It is important to complement the arsenal of educational complexes with new social technologies, encouraging children and adults to independent public action

We carried out the comparative study of the effect of inhibitor-loaded nanocontainers on the corrosion protection performance of polyester powder coatings by neutral salt-spray test (5% NaCl, 35 °C, different time). Halloysites and mesoporous silica particles loaded with corrosion inhibitor 8-hydroxyquinoline were homogeneously distributed in powder coating effectively reducing corrosion of the metal substrate over 1000 h of salt-spray test. Addition of only 2 wt.% of inhibitor encapsulated either in halloysites or in mesoporous silica particles to the powder coating is sufficient to decrease the delamination effect by >4 times and to suppress the formation of the blisters on the low carbon steel substrates.

The model substance 2-methylbenzothiazole with moderate amphiphilic properties, which is used as liquid corrosion inhibitor, was encapsulated via interfacial polymerization with three types of polymers with high cross-link density: polyurethane, polyurea, and polyamide. The structure of the resulting capsules depends on the type of polymer. Polyurethane and polyurea formed “compact” particles with 2-methylbenzothiazole homogeneously distributed in the polymer matrix, while in the case of polyamide core–shell structures were formed. “Compact” morphologies form due to the high affinity of the liquid capsule component to the polymer; core–shell morphology is formed when the affinity is low. Application of the Hansen solubility parameters approach allows prediction and control of the morphology of capsules made of cross-linked polymers.

Designing of novel self-healing materials possessing an active feedback on various destructive factors is one of most quickly developing areas in contemporary material engineering. Self-healing and self-protecting coatings represent one of particular classes of these materials that able on damage to recover their anticorrosive or antifouling function. Most established approach to impart to the coating this ability is nowadays the use of container-based structures when the protective agent trapped in containers is embedded in the coating matrix. There are different ways to produce containers for the further incorporation into coating but the role of emulsion route in the containers preparation is probably predominant. Herein, the contemporary achievements in the field of emulsion encapsulation are reviewed. Several types of containers for biomimetic functional coatings synthesized via emulsion as an initial system are presented based mainly on the earlier published and very recently obtained results of our research group. An overview is given of some interfacial physical and chemical methods utilized for the transformation of emulsion droplets into nano- or microscaled containers showing their specific advantages and drawbacks. Successful incorporation of containers in the diverse types of coatings showed is promising for novel materials production in many application fields.

New smart anticorrosion coatings based on a combination of passive and active parts were developed. The active part is presented by polyurethane microcontainers loaded with alkoxysilanes possessing a long hydrophobic tail. High efficiency of the coating is achieved by the combination of passivating and water-repelling properties of the loaded material.

We demonstrate a new one-batch approach to the fabrication of a biocompatible Ca-alginate film with embedded vitamin E-loaded microspheres that could be used for planar dermal drug delivery. Stable vitamin E microspheres, coated with gum acacia, are produced by ultrasonic treatment of a two-phase liquid system. The Fourier transform infrared spectroscopy indicates an interaction between biopolymer functional groups induced by ultrasonication. Confocal laser fluorescence microscopy, scanning electron microscopy (SEM) and atomic force microscopy (AFM) demonstrate a homogeneous microsphere distribution within the Ca-alginate polymer film. The kinetics of in vitro vitamin E release found for the polymer film with entrapped microspheres was much more sustained (100% in 96 h) compared to the polymer film with vitamin E embedded in the free state (100% in 5 h). The novelty of the proposed research involves the ultrasonic fabrication of loaded microspheres and formation of biodegradable coating directly doped with microspheres.

Oil-in-water (o/w) Pickering emulsions stabilized with silica nanoparticles were prepared. Droplets of diethyl phthalate (oil phase) act as reservoirs for 8-hydroxyquinoline (8-HQ), which is used as (a) the hydrophobizing agent for the silica particles and (b) an encapsulated corrosion inhibitor for application in active feedback coatings. The hydrophobization of silica nanoparticles with 8-HQ is determined by the amount of this agent adsorbed on the nanoparticle surface. The latter is governed by the 8-HQ concentration in the aqueous phase, which in turn depends on the degree of protonation and fir ally on the pH. We observe three ranges of 8-HQ adsorption value with respect to nanoparticle hydophobization: (I) insufficient, (2) sufficient, and (3) excessive adsorption by the formation of an 8-HQ bilayer, where only case 2 leads to the necessary nanoparticle hydrophobization. Hence emulsions stable in a narrow pH window between pH 5.5 and 4.4 follow. Here functional molecules are sufficiently charged to compensate for the charges on silica nanoparticles to make them interfacially active and thus able to stabilize an emulsion but they are still to a large extent uncharged and thereby remain in the oil phase. The emulsification is reversible upon changing the pH to a value beyond the stability region.

The influence of ultrasound waves (20 kHz) of high intensity (40 W·cm−2) on preformed citrate-protected gold nanoparticles (average diameter 25 ± 7 nm) is demonstrated in pure water and in the presence of surfactants. Ultrasonic treatment for 20 min is sufficient to fuse gold nanoparticles at the contact in a dumbbell-like structure. Gold nanoparticles acquire a worm-like or ring-like structure after 60 min of sonication in water. Fused nanoparticles with spherical or oval shapes are formed after ultrasonic treatment in the presence of sodium dodecyl sulfate or dodecyl amine solutions. Dispersion of nanoparticles is found as an additional process during sonication, which is the weakest in pure water. The crystalline face centered cubic structure of ultrasonically treated gold nanoparticles is defected by ultrasound. The reported results could be of interest for ultrasonic melting of inorganic materials at the nanoscale to produce metal structures with different morphologies and properties.

A simple approach for the protection of hydrogen storage materials is based on interfacial polymer precipitation induced by solvent evaporation. Sodium borohydride is successfully protected with a polystyrene shell by co-precipitation. This shell provides a hydrophobic barrier for water diffusion into the container interior. Simultaneous nucleation of sodium borohydride inside the droplets of the disperse phase and formation of a surrounding polystyrene shell during gradual solvent evaporation led to the development of structures consisting of a sodium borohydride core and a polymer shell. Confocal fluorescence microscopy, scanning electron microscopy and transmission electron microscopy reveal the crystalline interior and polymer shell of the fabricated microcontainers. FTIR spectroscopy proves the presence of a sodium borohydride core and a polystyrene shell. The stability of sodium borohydride microcontainers is increased as compared to the unprotected material by 2.5 times during storage at 100% humidity.

The key element of a novel generation of protective coatings with feedback activity to the external and internal triggers is an embedding of smart nano- or microcontainers into the coating matrix. When implanted in various types of coating matrices, these containers with a sensitive polymeric shell and water or oil interior provide controlled release of the encapsulated active materials upon action by external stimuli. In the article at hand we survey recent achievements in this new field of development and application of filled sensitive containers in biomedical and self-healing protective coatings. Diverse stimuli-responsive and self-repairing systems (implants, matrices, coatings) in different branches, from medicine to corrosion protection, are presented and their advantages as well as drawbacks are discussed in terms of the field-specific protection efficiency.

Emulsions are successfully applied in many fields of human activity. When used as liquid colloidal carriers the stability of emulsion droplets against coalescence often requires improvement. Additional protection against colloidal degradation or environmental stresses is almost an unavoidable precondition for employment of emulsion formulations in food industry, pharmaceutics, cosmetics and medicine. In this review, a variety of current approaches to increase emulsion stability were summarized beginning systems stabilized by low molecular weight surfactants and spanning over to finely adjusted nanoengineering systems based on multilayer assemblies with very specific functionalities matching the application demand. Special attention is paid to applications in particular fields.

Fluorescence dyes Rhodamine and Fluorescein do not influence the adsorption layer properties of labelled β-lactoglobulin when used at sufficiently low concentration. However, due to interference of light absorption and emission by the dye with the registration of ellipsometric signals in surface ellipsometry experiments, errors can result. To avoid erroneous adsorption layer data, the laser light sources in ellipsometers should be selected such that the sensitivity peak of the photo detector is within a sufficient distance to the absorption and emission wavelengths of the dye.

A sonochemical approach has effectively been applied to prepare aqueous dispersions of air-filled nanostructured quartz silica shells from surface-engineered amorphous silica nanoparticles. The non-equilibrium nature of the cavitation process and high temperature and pressure in the cavitation microbubble can lead to partial crystallization of the amorphous silica nanoparticles producing the quartz phase and a high degree of interconnection between the silica nanoparticles in the microsphere shells. The very high stability of the silica shells against collapse and aggregation is determined by the hydrophobic nature of the silica nanoparticles. Because of the shell thickness and its high density caused by sintering of the silica nanoparticles, the gas (liquid) permeability through the shell is limited thus prolonging the life time of the air-filled nanostructured silica shells.