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The procedures for synthesizing fused 1,2,5-chalcogenadi-azoles and 1,2,3-dithiazoles by direct exchange of one chalcogen atom for another, their scope and reaction pathways are discussed in this focus review.

Valproic acid (VPA) is a widely used anticonvulsant that is effective against most seizure types. Due to its teratogenic effects, its use should be avoided among females of childbearing age, unless other treatments are ineffective or not tolerated. This study aimed to determine the prevalence of VPA use in 2005-2018 in Estonia, with special attention to females of childbearing age.In this retrospective nationwide population-based cohort study, outpatient prescription data from the national health insurance provider were used. Annual sex- and age-specific prevalence rates were calculated, and changes therein during the study period were evaluated.The annual rates of VPA use among females of childbearing age increased significantly in 2005-2014. After 2014, the increasing trend stopped; in 2014-2018, the prevalence rates declined slightly [prevalence rate ratio (PRR), 0.94; P = 0.136]. In males of the same age, the increasing trend continued (PRR, 1.08: P = 0.028). Among neurologists, the rate of VPA prescription to females aged15 and 15-44 years decreased during 2014-2018 (PRR, 0.74; P0.001 and PRR 0.72; P0.001, respectively); no change in prescription frequency was seen among psychiatrists during this period.The increasing trend in VPA usage among females of childbearing age in Estonia stopped after 2014, when the European Medicines Agency's strengthened restrictions on VPA use in females were communicated extensively in Estonia. The level of awareness of VPA's harmful effects during pregnancy is lower in the psychiatric community.

Cu2ZnSnS4 (CZTS) thin films were synthesized by sulfurization of Cu/Sn/Cu/Zn precursors electrochemically deposited on titanium foil substrates. A part of the precursor samples were pre-annealed at 250 °C for 30 min. Sulfurization of the samples was carried out at 500 °C for 2 h. It was obtained that preliminary annealing leads to exclusions of CuSn and CuZn4 phases from the precursor composition. When using the as-deposited precursors, the CZTS phase is formed with preferred orientation along the [211] and [213] directions, and petal-shaped crystallites on the film surface form. Using annealed precursor films, the CZTS phase is formed with porous morphology and without pronounced preferred orientation. The CZTS films obtained from as-deposited precursors contain lack of tin (Cu/(Sn + Zn) = 0.95 and Zn/Sn = 1.95 ratios of at.%), whereas the annealed precursor lead to formation of the films with elemental composition close to stoichiometry (Cu/(Sn + Zn) = 1.13 and Zn/Sn = 1.06 ratios of at. %). The films obtained from annealed precursors possess lattice parameters close to the data for bulk crystals, which indicates high structural perfection of CZTS.

An efficient synthesis of [1,2,5]oxadiazolo[3,4-d]pyridazine 1,5,6-trioxides (1) from 3,4-bis(hydroxyimino)methyl)-1,2,5-oxadiazole 2-oxides using a mixture of concentrated nitric and trifluoroacetic acids has been developed. The scope of the unconventional reaction was established. The 4,7-dinitro[1,2,5]oxadiazolo[3,4-d]pyridazine 1,5,6-trioxide 1f represents a new high energy compound, unfortunately with low thermal stability. The parent [1,2,5]oxadiazolo[3,4-d]pyridazine 1,5,6-trioxide 1c was studied by single-crystal X-ray diffraction analysis which revealed a planar molecule with an unusually long intracyclic N N bond of 1.668(5) A and unexpected exo-cyclic bond angles at the nitroxyl nitrogen atoms. In the crystal, the molecules of 1c are bound to each other by strong π-π stacking and C H⋯O hydrogen bonding interactions into a three-dimensional framework that results in a high crystal density of 1.833 gcm−3.

The study of migration mechanism of triple junctions of tilt boundaries with misorientation axes 〈1 1 1〉 and 〈1 0 0〉 on the example of nickel was performed by the method of molecular dynamics. It was found that migration and elongation of low-angle 〈1 0 0〉 boundaries is realized through slipping of pair grain-boundary dislocations with the subsequent change of dislocations-partners. During the changing of dislocation-partners, the decomposed dislocations slipped, the climb of the dislocations was not observed. The migration of 〈1 1 1〉 tilt boundary occurred as a result of the combined action of two mechanisms: the mechanism described above and the mechanism consisting in the joint slipping of pair grain-boundary dislocations, which, in contrast to grain-boundary dislocations in 〈1 0 0〉 boundaries, have common slip planes. The second mechanism has relatively low activation energy, as a result of which 〈1 1 1〉 boundaries are much more mobile than 〈1 0 0〉 boundaries. During the triple junction migration, at an elongation of the low-angle boundary, a new geometrically necessary dislocation appeared, as a rule, from the migrating triple junction, after which the dislocation-partners are redistributed at the elongating boundary near the junction as a result of their split and subsequent merging with the formation of zigzag atomic displacements.

To provide fault tolerance, modern distributed storage systems use specialized network topologies and consensus protocols that create high overheads. The main disadvantage of existing specialized topologies is a difficulty to implement an efficient data placement that takes into account locality of the data. In scientific problems very often it is necessary to provide the semantic proximity of the data at the nodes of the distributed system. Core drawback of modern consensus protocols is that most of them use messaging through broadcasting, which is impossible for large amounts of data and storage nodes. With more stringent requirements for a fault tolerance, e.g. requirement for resistance to Byzantine errors [1], ensuring of data localization becomes nearly impossible. The purpose of this paper is to implement a distributed consensus protocol that preserves data localization and is resistant to Byzantine errors. Theoretical tasks: a) consider how to implement distributed services based on finite state machines; b) consider how to ensure Byzantine fault tolerance; c) consider methods for organizing the semantic proximity of data. Practical tasks: a) develop ways to jointly ensure the Byzantine fault tolerance and locality of data; b) study the shortcomings of the joint provision of Byzantine fault tolerance and locality of data; c) develop a protocol of Byzantine consensus using semantic links between data; d) analyze the performance of the developed protocol within the framework of applied tasks. The object of the study is a distributed data storage system with the requirement for Byzantine fault tolerance. The subject of this study is the provision of Byzantine fault tolerance in conjunction with the use of semantic links between the data. The subject of this study has never been the subject of a special scientific study. Separate scientific foundations of this problematic set in the present study were developed in separate works on Byzantine fault tolerance, local hash methods and dimensional reduction.

Planctomycetes of the family Gemmataceae are strictly aerobic chemo-organotrophs that display a number of hydrolytic capabilities. A member of this family, Telmatocola sphagniphila SP2T, is the first described planctomycete with experimentally proven ability for growth on cellulose. In this study, the complete genome sequence of strain SP2T was obtained and the genome-encoded determinants of its cellulolytic potential were analyzed. The T. sphagniphila SP2T genome was 6.59 Mb in size and contained over 5200 potential protein-coding genes. The search for enzymes that could be potentially involved in cellulose degradation identified a putative cellulase that contained a domain from the GH44 family of glycoside hydrolases. Homologous enzymes were also revealed in the genomes of two other Gemmataceae planctomycetes, Zavarzinella formosa A10T and Tuwongella immobilis MBLW1T. The gene encoding this predicted cellulase in strain SP2T was expressed in E. coli and the hydrolytic activity of the recombinant enzyme was confirmed in tests with carboxymethyl cellulose but not with crystalline cellulose, xylan, mannan or laminarin. This is the first experimentally characterized cellulolytic enzyme from planctomycetes.

The longitudinal response of a buried 1400 mm diameter reinforced concrete pipeline with gasketed bell-and-spigot joints subjected to traffic loading is investigated through three-dimensional numerical simulation. The soil is represented by a non-linear elastic perfectly plastic constitutive model that accounts for the reduction of soil stiffness with strain. Reasonable agreement is found between the computed results and the centrifuge test results. The simulation reveals that four pipe segments and three joints are influenced significantly under the surface load. Variation in gasket stiffness has only minor influence on the longitudinal response of the buried pipeline. In contrast, variation in soil stiffness has a dominant influence. Due to the asymmetric geometry of the bell-and-spigot joint, the pipeline movement is not symmetrical, whether the load is applied above a joint or above the mid of a pipe segment. The longitudinal deformation of jointed pipeline is highly discontinuous, with concentration of rotation and shear displacement at the joints. The maximum joint rotation always occurs when the surface load is directly above the joint, while the maximum joint shear displacement is generated when the load is applied above the adjacent pipe contributing the spigot. The most unfavorable load position to generate the maximum joint shear displacement depends on the burial depth and can be estimated by a simplified method.

The current level of geoscience advancements enables analysis of the Earth as a highly complex system with many components, like hydrosphere, lithosphere, and atmosphere, which interact within and with others. Large amounts of observational data and simulation data generated by numerical models need to be analyzed in order to extract valuable knowledge from them. Visualization is a very important part of data analysis since it provides an easy and fast way to assess the data and understand, which parts of it are of particular interest and whether there are any errors in the dataset. The most efficient type of tools for meteorological data visualization are geographic information systems (GIS) because they provide great functionality for manipulating geospatial data. In this paper, we describe the processing framework, which can be efficiently used as a backend for GIS by providing rapid access to the data located at the remote storage nodes. Experimental results demonstrate that developed framework allows real-time data access and can successfully handle a large number of simultaneous requests.

During vacations, people try to explore new places, but it is impossible for tourists to see all interesting locations. In this paper, we shed the light on differences between favorite places of tourists and locals using Instagram profiles. The time windows based identification method is proposed to distinguish visitors from residents. The list of potential tourists’ attraction points in Saint Petersburg was obtained by analysis of locals’ popular places.

Fluorescent D-A1-π-A2 dyes containing the 9-hexyl-9H-carbazole electron-donor unit and 2,1,3-benzochalcogenadiazoles as electron-withdrawing, were synthesized. These dyes displayed high luminescence quantum yields up to 20% in the solid phase and 80% in solutions. A series of ClsOLEDs with high luminance up to 6256 cd/m2 and low color temperature (1800–1900 K) based on these dyes were constructed. The electroluminescence color temperature of the fabricated OLEDs is independent of the operating voltage making these compounds potentially very useful for night time illumination. It was shown that the aggregation process of the investigated dyes led to the formation of planar crystalline structures. Scanning electron microscopy (SEM) and fluorescence lifetime imaging (FLIM) experiments, showed that luminescence quenching caused by interactions between aggregates of different sizes takes place. Spectroscopic studies were supported by Density Functional Theory (DFT) and Time Dependent Density Functional Theory (TD-DFT) calculations. As a result, we elucidated that replacement of [1,2,5]chalcogenadiazolo[3,4-c]pyridines by 2,1,3-benzochalcogenadiazoles led to a substantial improvement in intramolecular charge transfer (ICT) from the donor to acceptor units due to favourable distortion of the excited state geometry.

Numerous experimental studies have shown that the formulation of a quality AlxIn1-xN crystal is undeniably challenging, due to mismatch of certain physical properties between its parent blocks. Prior knowledge regarding proper mixture of aluminium and indium could be helpful in the blending of this crystal. Here, by applying ab initio crossbreed evolutionary computations, extensive search for the thermodynamically and practically stable composites of AlNInN was performed. Set at atmospheric pressure, the comprehensive calculations brought forth a thermodynamically stable structure Al4In2N6 (Cmc21) along with five metastable compounds in AlIn7N8 (P3m1), Al5InN6 (P31m), Al2In4N6 (Cc/Aa), Al3In3N6 (Cm/Am) and Al6In2N8 (P21). Electronic structure calculations within Density Functional Theory and Bader charge analysis are also discussed. All structures are revealed to be mixed bonding direct semiconductor with GW corrected gap in the range of 0.5–6.0 eV.

A short and efficient synthesis of 1-(2-oxido-1,2,5-oxadiazol-3-yl)alkyl nitrates from 3-alkyl-1,2,5-oxadiazole 2-oxides, using a mixture of nitric and sulfuric acids in chloroform, has been developed. The scope of the unconventional reaction was established; its mechanism likely included a new Grob-type fragmentation.

Purpose The aim of this study was to compare the risk of metabolic syndrome (MS) and evaluate related factors for MS among people with epilepsy treated with valproate (VPA) or carbamazepine (CBZ). Methods A total of 213 adult patients with epilepsy treated with VPA ( n =118) or CBZ ( n =95) monotherapy were included in the study. Participants were evaluated for the presence of MS, diagnosed according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Results In the multiple logistic regression analysis, the risk of MS in CBZ- and VPA-treated patients was similar (odds ratio [OR]=0.99; 95% confidence interval [CI], 0.43–2.26; P =0.979). A lower proportion of CBZ-treated patients had abnormally low levels of high-density lipoprotein cholesterol (OR=0.10; 95% CI, 0.02–0.42; P =0.002), whereas a lower proportion of VPA-treated patients had abnormally high concentrations of fasting blood glucose (OR=0.30; 95% CI, 0.13–0.69; P =0.004). Females treated with VPA tended to have a higher risk of MS (OR=1.48; 95% CI, 0.50–4.41; P =0.485) compared to males (OR=0.74; 95% CI, 0.28–1.96; P =0.551), although this difference was not statistically significant. Conclusion Although the overall risk of MS was similar in patients with epilepsy who were treated with VPA or CBZ, the distribution of MS components differed between treatment groups. Patients treated with CBZ or VPA less frequently had decreased high-density lipoprotein cholesterol levels or increased blood glucose concentrations, respectively. Females on VPA treatment could be at higher risk of MS than males.

The existing or potential applications of fused 1,2,5-thia- and -selenadiazoles in material science predetermined the quickly growing interest in these heterocyclic systems. This digest summarizes the recent progress in synthetic approaches, functionalization and employment of smart molecular materials based on these heterocycles. New starting materials as well as unknown and unexpected procedures, including direct chalcogen exchange in 1,2,5-chalcogenadiazole rings, are reviewed. The functionalization of fused 1,2,5-thia- and -selenadiazoles by cross-coupling reactions, nucleophilic substitution by the Buchwald-Hartwig strategy and co-polymerization are emphasized. Important applications, especially in the field of organic photovoltaics, are considered.

The novel donor building-block - 9-(p-tolyl)-2,3,4,4a,9,9a-hexahydro-1H-carbazole was designed and employed in the synthesis of dye-sensitized solar cell (DSSCs). An effective, high-yielding synthesis of 4,6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9-(p-tolyl)-1,2,3,4,4a,9a-hexahydrocarbazole from 1,2,3,4,4a,9a-hexahydrocarbazole was realized. Three new metal-free organic sensitizers, containing the new donor building block were prepared by a stepwise approach from 4,7-dibromobenzo[c][1,2,5]chacogenadiazoles. A 2,1,3-Benzothiadiazole dye containing hexahydrocarbazole donor, thiophene as π-spacer and cyanoacrylate as anchoring electron acceptor showed photovoltaic properties higher than the well-known WS-2 sensitizer with PCE = 5.86 %. Although benzoxa- and –selenadiazole dyes have a bathochromic shift (24−30 nm) in the UV–vis spectra, and smaller energy gap Eg (about 0.1 eV), they have lower photovoltaic parameters, including PCE of 1.5–2.3 %. Introducing a new donor 9-(p-tolyl)-2,3,4,4a,9,9a-hexahydro-1H-carbazole into the construction of the DSSCs has broadened possibilities for the optimization of their photovoltaic properties.

The consequences of population bottlenecks for dental phenotypes are studied in Arvicolinae, a subfamily of cricetid rodents widely used as a proxy of environmental change and an index group for relative dating and correlation of the Quaternary deposits throughout the Holarctic. Comparative morphological analysis reveals similar phenotypic shifts in populations of extant Dicrostonyx, Lemmus, Myopus, Microtus surviving bottlenecks in captivity or in the areas favouring genetic drift (coastal zones and islands, patchy landscapes in the mountainous areas, declining peripheral populations). Six to ten founders is enough for an isolated population to reproduce the full range of species-specific variability in fitness-related characters (crown complexity and occlusal regularity) during the first two generations, while the average values of both characters exhibit founder dependence. When lasting longer than 3 generations, bottlenecks increase diversity owing to 1) the accumulation of rare traits of complexity and regularity inherited from the founders and 2) inbreeding impacts (the loss of advanced morphology and appearance of extra elements in places of the lophs and cusplets of an ancestral cricetid molar). Founder-related and inbreeding-induced simplifications of dentition might potentially lead to biochronological discrepancies in the fossil record of Arvicolinae. To detect possible biases in biochronological data, the phenotypic markers of close breeding are identified. Application of the results to the fossil record of collared lemmings from the north of West Siberia allows hypothesising the periods of increased genetic drift in the ancestral forms of Dicrostonyx in the late Middle Pleistocene and in the early Late Pleistocene.

Background Minimal research has explored community dwelling adults’ knowledge of the human papillomavirus (HPV) in relation to head and neck cancer (HNC). The purpose of this study was to report on community dwelling adults’ knowledge of HPV in relation to infection, symptoms, and the development of HNC. Methods Cross-sectional assessment of community-dwelling adults on history of behavioral risk factors for HNC, health literacy, and knowledge regarding HPV in relation to HNC. Results Of those who completed the measure of health literacy, 17.1% read at or below an 8th grade level. Participants reported a range of history of behaviors putting them at increased risk for HPV and HNC. Respondents answered an average of 67.2% of HPV questions correctly, only one person answered all 15 questions correctly. There were no differences in knowledge of HPV in relation to HNC based upon demographics, suburban versus urban location, health literacy, or cancer history. Conclusions Adults reported a range of behaviors associated with an increased risk of HPV transmission but also displayed large gaps in knowledge regarding HPV in relation to HNC.

The photosensitive thin kesterite films of Cu1.5Zn1.15Sn0.85S4 were prepared by the reactive magnetron sputtering of composite targets followed by annealing with the formation of a kesterite phase.