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The results from measuring the capacity of thin-film solid-state lithium-ion batteries (SSLIBs) Ti|Si@O@Al|LiPON|LiCoO2|Ti, Ti|Si@O@Al|LiPON|LixV2O5|Ti, and Ti|LiPON|LiCoO2|Ti at different charge currents are reported. It is shown that the dependence of the capacity on the current density Q(j) follows Peukert’s law, which is characterized by a low value of Peukert’s exponents in the region of low currents and a high value of the exponents in the region of high currents. Peukert’s exponent for the anode-free cell remains constant through the entire range of current density variation. A model for SSLIB capacity based on the balance of ion (diffusion and drift) and electron currents is proposed. The model predicts a Q(j) dependence well approximating the experimental results and fitting Peukert’s law. The model allows a qualitative interpretation of the change in the Peukert exponent with increasing current density, based on the effect of the charge current saturation.

In the present paper, we describe several coleoid jaws discovered in the lower Toarcian black shales, cropping out along the Vilyui River (Yakutia, Russia). This is the first record of a Lower Jurassic coleoid jaw outside Europe and the first report of such a finding from the Mesozoic of Siberia. The described coleoid jaws demonstrate the same mode of preservation and morphology as the coeval jaws previously reported from Europe. Their preservation in Siberia became possible due to the widespread occurrence of black shale facies associated with the early Toarcian oceanic anoxic event (TOAE).

Here, we report a novel, easy-to-implement scalable single-step procedure for the fabrication of a solid-state surface-enhanced photoluminescence (SEPL) sensor via the direct femtosecond (fs) laser patterning of monocrystalline Si wafers placed under the layer of functionalizing solution simultaneously containing a metal salt precursor (AgNO3) and a photoluminescent probe (d114). Such laser processing creates periodically modulated micro- and nanostructures decorated with Ag nanoparticles on the Si surface, which effectively adsorbs and retains the photoluminescent sensor layer. The SEPL effect stimulated by the micro- and nanostructures formed on the Si surface localizing pump radiation within the near-surface layer and surface plasmons supported by the decorating Ag nanoparticles is responsible for the intense optical sensory response modulated by a small amount of analyte species. The produced SEPL sensor operating within a fluidic device was found to detect sub-nanomolar concentrations of Hg2+ in water which is two orders of magnitude lower compared to this molecular probe sensitivity in solution. The fabrication technique is upscalable, inexpensive, and flexible regarding the ability to the control surface nano-morphology, the amount and type of loading noble-metal nanoparticles, as well as the type of molecular probe. This opens up pathways for the on-demand development of various multi-functional chemosensing platforms with expanded functionality.

In this article, the relevance of the study of gears with a complex non-involute profile of the tooth flanks is justified. For the subsequent study of non-involute gearings, the task of mathematical modeling of the profile of a gear-cutting rolling tool for machining of noninvolute gear wheels is solved. As a profile of the tooth flank of a rack, a certain section of one of the previously simulated flat kinematic curves is considered. Based on the algorithm for calculating the profile of envelope surfaces, a method for geometric analysis of the process of surfaces shaping by rolling gear cutting tools has been developed. Using computer graphics, the sequential shaping of the teeth space of non-involute gear wheels processed by rolling gear cutting tools with a given tooth profile was studied

The second article of the cycle, prepared by the Center of Ukrainian Studies IE RAS for the 30th anniversary of the state sovereignty of Ukraine, is devoted to foreign policy. What is its paradigm, is it there, has it changed, and if so, how and why? The article contests the view that Ukraine’s foreign policy has no strategy and is entirely subject to external influences. The author believes that Ukraine has it, and the experience of its formation is unique and therefore interesting. It is difficult to find in Europe another great nation-State, born for so long and so difficult, which would have to seek its place in the world at a time when the world itself and the institution of the nation-state have begun to change so profoundly. The article substantiates the view that Ukraine’s foreign policy paradigm was formed in these circumstances on objective internal grounds with strong external influences and, Despite the frequent changes in political leaders and the adjustment of external political discourse, this continued and is likely to continue in the future.

Here, we show that direct femtosecond laser nanostructuring of monocrystalline Si wafers in aqueous solutions containing noble-metal precursors (such as palladium dichloride, potassium hexachloroplatinate, and silver nitrate) allows for the creation of nanogratings decorated with mono- (Pd, Pt, and Ag) and bimetallic (Pd-Pt) nanoparticles (NPs). Multi-pulse femtosecond-laser exposure was found to drive periodically modulated ablation of the Si surface, while simultaneous thermal-induced reduction of the metal-containing acids and salts causes local surface morphology decoration with functional noble metal NPs. The orientation of the formed Si nanogratings with their nano-trenches decorated with noble-metal NPs can be controlled by the polarization direction of the incident laser beam, which was justified, for both linearly polarized Gaussian and radially (azimuthally) polarized vector beams. The produced hybrid NP-decorated Si nanogratings with a radially varying nano-trench orientation demonstrated anisotropic antireflection performance, as well as photocatalytic activity, probed by SERS tracing of the paraaminothiophenol-to-dimercaptoazobenzene transformation. The developed single-step maskless procedure of liquid-phase Si surface nanostructuring that proceeds simultaneously with the localized reduction of noble-metal precursors allows for the formation of hybrid Si nanogratings with controllable amounts of mono- and bimetallic NPs, paving the way toward applications in heterogeneous catalysis, optical detection, light harvesting, and sensing.

Potato spindle tuber viroid (PSTVd) is a small infectious non-coding circular RNA causing diseases of important crops, including tomato and potato. The symptoms vary from mild to severe depending on the viroid strain, the host plant variety, and the environmental conditions. The molecular mechanisms underlying the development of particular disease phenotypes remain elusive. The PSTVd strain NicTr-3 causes severe disease symptoms on Solanum lycopersicum cv. Rutgers and Solanum tuberosum cv. Colomba. It was found that after three cycles of propagation in tomato cv. Rutgers, infection of potato cv. Colomba with NicTr-3 resulted in very mild symptoms including smaller size of tubers and delayed leaf senescence. Sequence analysis of PSTVd clones isolated from tomato inoculum revealed the presence of mutated variants of genomic RNA. Transcriptome analysis carried out on leaves showed a considerable difference between infected and healthy plants at 14 dpi and 30 dpi. Interestingly, the response of potato plants to the attenuated PSTVd strain revealed a large number of DEGs associated with initiation of dormancy with a considerable increase in the vegetation period. The second vegetative generation (tuber-derived plantlets from control healthy and PSTVd-infected plants) was characterized by similar phenotypes and transcriptomes. Thus, here we describe a case of attenuation of a severe PSTVd strain after continuous propagation in tomato. It would be of interest to consider the attenuated viroid strains as a potential biocontrol agent or vaccine against this type of pathogenic RNA.

The continuously increasing flow of toxic heavy metals to the environment due to intensive industrial activity and tightening requirements with regard to the content of metal ions in drinking and discharged waters urges the development of affordable and sensitive devices to the field control of pollutants. Here, we report a new thiated Rhodamine-lactam probe for Hg2+ detection and demonstrate how its sensitivity can be increased via the incorporation of the probe molecules into the optically transparent siloxane-acrylate coatings on polymethyl methacrylate and, alternatively, into the water-dispersible light-harvesting FRET nanoparticles (NPs), in which dye cations are separated by fluorinated tetraphenylborate anions. We have shown that the optimization of the FRET NPs composition had allowed it to reach the antenna effect of ~300 and fabricate “off/on” sensor for Hg2+ ion determination in aqueous solutions with the detection limit of ~100 pM, which is far below the maximum permissible concentration (MPC) of mercury in drinking water recommended by the World Health Organization. Although this work is more proof-of-concept than a ready-to-use analytical procedure, the suggested approaches to fabrication of the FRET NPs based on the popular rhodamine-lactam platform can be used as a background for the development of low-cost portable sensing devices for the extra-laboratory determination of hazardous metal ions.

Transition metal carbides, such as molybdenum carbides, are promising substitutes for noble metals as low-cost, durable electrocatalysts. Under ambient conditions, however, these carbides are subject to oxidation due to their oxophilic nature. The partially oxidized surface may possess both oxygen-modulated metallic-like hydrogen adsorption sites and Brønsted-acidic hydroxyl sites. However, the impact of surface oxidation on electrochemical processes such as the hydrogen evolution reaction (HER) has rarely been studied. Here, we synthesized β-Mo2C catalysts and oxidized their surfaces electrochemically to varying extents to study the effects of surface oxidation on HER activity. The degree of surface oxidation was controlled by applying different potential windows to metal carbide catalysts. The samples with varying degrees of surface oxidation were tested for their HER activity. Experimental data indicate that the Tafel slope for the HER and double-layer capacitance were negatively affected by surface oxidation, particularly due to the loss of carbon and the formation of electrochemically less active surface oxides. The surface oxidation was studied experimentally by X-ray photoelectron spectroscopy and simulated using density functional theory (DFT), ab initio thermodynamics, and charge transfer estimates. Our DFT calculation results suggest that the model β-Mo2C (011) surface favors the adsorption of O* from water during the electrochemical oxidation, giving rise to the anodic current. Oxygen atoms preferentially interact with surface C sites, forming stable –C＝O species and oxycarbide-like surfaces. Highly oxidized surfaces become kinetically unstable and undergo a deeper, substitutional oxidation through –C＝O replacement by O*, forming a thermodynamically stable Mo(IV) surface oxide, where each Mo atom coordinates with up to six O atoms. The rate-limiting step switches from CO desorption, occuring within the potential window from 0.28 to 0.51 V, to water dissociation above 0.51 V. The computational results agree well with experimental observations, such as the onset potential (0.6 V) for rapid surface oxidation. This work helps to unravel the details of evolution of surface sites during an oxidation process of molybdenum carbides along with their effects on catalytic properties and lays the foundation for their practical use in various applications. [ABSTRACT FROM AUTHOR]

Bioclaustrations are among the best ways that parasitic associations are preserved. A new bioclaustration, Haplorygma productidophilia csp. nov., is here described from the ventral interior of the Carboniferous productid brachiopod Eomarginifera lobata. The location and morphology of the structures in the ventral valve differ from the structure in the dorsal valve, suggesting that two different organisms infested the shells of Eomarginifera lobata. It is possible that whether it was ventral or dorsal valve was an important selection criterion for the infesting organisms, which were likely parasites. The proportion of infested productids was low in the population (5.8%). This low infestation rate could indicate that productids had effective methods for resisting parasites, or that the parasites were ineffective in spreading through the brachiopod population. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic in Ukraine, from March 2020 to June 2022, witnessed distinct waves, each characterized by an increase in cases and fatalities. Next-generation sequencing has been used to understand the impact of viral variants on the pandemic situation in Ukraine. We analyzed SARS-CoV-2 genome sequencing data to identify viral variants circulating during each wave. By integrating epidemiological information, we established associations between viral variants and disease spread. The adoption of next-generation sequencing for SARS-CoV-2 surveillance in Ukraine, despite limited resources, yielded adequate and trustworthy results, reflecting the pandemic situation. After the Russian military invasion of Ukraine in February 2022, a large number of refugees crossed the border with neighboring countries. Mutation analysis on sequencing data from Ukraine and Poland was used to estimate the exchange of SARS-CoV-2 variants between the countries during this period. Omicron subvariants detected in both countries were similar. The analysis of SARS-CoV-2 sequences from Poland and Ukraine revealed shared nucleotide mutations that can be used to identify the directions of spreading. [ABSTRACT FROM AUTHOR]

The influence of nonuniformity properties of the LiCoO2 cathode film deposited by magnetron sputtering on the capacity of all-solid-state thin-film lithium-ion batteries (ASSLIB) was studied. It was found that the film nonuniformity corresponds to the magnetron plasma density distribution and the angular distribution of sputtered particles. The capacity distribution of the ASSLIB with LiCoO2 cathode depending on the distance to the substrate center was studied. The maximum capacity corresponded to the dense part of the toroidal region of the magnetron plasma. It was determined that the main causes of batteries capacity decline in the central part and on the edge of the substrate are the impurity phase of lithium cobaltate and the smaller thickness of the cathode layer, respectively. [ABSTRACT FROM AUTHOR]

The authors study the effect of the tungsten oxide in the supports of 0.5% Pt/WOx-Al2O3 catalysts on their acidity, deposited platinum dispersity, and catalytic properties in the hydrodeoxygenation of sunflower oil. It is shown that the of Brønsted acid sites on its surface grows, and the dispersity of deposited platinum in the ready catalyst is reduced when the content of the modifier is increased. The studied samples ensure complete sunflower oil conversion in a hydrogen atmosphere at a liquid weight hourly space velocity (WHSV) of 1 h−1, a temperature of 380°C, and a total pressure of 4 MPa the composition of the support. A nearly stoichiometric yield of C5+ products at a level of 82–86 wt % is attained. The acidic properties of the 0.5% Pt/WOx-Al2O3 system determine the possibility for synthesizing the components of diesels with high contents of iso-alkanes as a result of sunflower oil hydrodeoxygenation. Using a catalyst with a nominal tungsten content of 15 wt % WO3 brings the content of iso-paraffins up to 74% with complete conversion of the initial feedstock for no less than 24 h. [ABSTRACT FROM AUTHOR]

The authors study the effect of the type of zeolite (SAPO-11, ZSM-22, ZSM-23, and ZSM-12) in a support (ratio zeolite : Al2О3 = 30 : 70) on the physicochemical properties of Pt/Al2O3-zeolite catalysts and the composition of products from the hydrodeoxygenation of sunflower oil on them. The possibility of the complete hydrodeoxygenation of sunflower oil at temperatures of 320–350°C, a pressure of 4 MPa, and a weight hourly space velocity (WHSV) of 1 h−1 is shown with 75–82% yields of liquid products. The fraction of iso-alkanes and the yield of direct hydrodeoxygenation products grow along with the concentration of Brønsted acid sites in a catalyst in the order 1%Pt/Al2O3-ZSM-22 < 1%Pt/Al2O3-ZSM-12 < 1%Pt/Al2O3-ZSM-23 < 1%Pt/Al2O3-SAPO-11. [ABSTRACT FROM AUTHOR]

This article presents the process of chedderizatsii from a technological point of view and the General theory of cheese making. Chedderizatsii described as a process of restructuring of the cheese mass due to the reorientation of relations between multi-molecular associates of milk (casein micelles and fat globules). The algorithmic process chedderizatsii due to the natural cycle of transformation of milk components in the abomasum of calves of milk period. There is an acid-base range (pH 5,3 - 5,1), in which a certain dynamics of interaction of protein, fat, mineral and aqueous phases of milk is programmed. The role of carbonate milk buffer in cheese mass restructuring is shown. In the development of the group's natural rennet cheese with a pronounced process of chedderizatsii curd spontaneously (with the rapid increase in acidity) is structured - is of laminated fibrous structure, which is commonly associated with the structure of the "meat chicken breast", which is a consequence

Ukraine has completed a long period of transformation of its political regime. On the occasion of the thirtieth anniversary of State sovereignty, a discussion of its outcome is envisaged. One can look back on the road travelled. For 30 years it has been determined by the continuation of nation-building and the search for the right integrationist vector. With the formal completion of the former and the uncertainty of the latter, the danger of a continuing transformational crisis emerged. The article is devoted to the analysis of its nature and possible ways out of it. The nature of the «second transformative crisis» in Ukraine ambivalent. It can be both a factor of destabilization and degradation and an indication of the path to exit, stabilization and growth. Much, if not all, will depend on the elite’s willingness to rise above personal and corporate interests and its ability to learn from its own experiences, to consider external conditions and to offer development goals that can consolidate society. In the opinion of the author, the Association Agreement with the EU, in the process of its further implementation, could become a basis for targeting and a tool for achieving the objectives set. If successful, Ukraine’s experience of nation-building in the context of globalization may prove useful to other newly independent Eastern European States.

The review considers quarantine species and nematode pathotypes potentially dangerous for domestic potato production. Potatoes are affected by more than 30 types of parasitic nematodes, but the review focuses on the most harmful representatives of genera that cause great damage to potato production: Globodera, Ditylenchus, Nacob bus and Meloidogyne. Phytopathological and molecular methods of identification of species and pathotypes and the main achievements in studying the population variability of parasitic potato nematodes were analyzed. It was shown that due to the peculiarities of the life cycle of nematodes and lability of their genomes, the genetic variability of these organisms is very high, which creates a threat of forming new pathogenic genotypes of the parasites. The information about the intra- and interpopulation variability of nematodes is important for studying the ways of introduction and distribution of separate species, as well as for searching for the correlations of molecular markers with the pathotype. Phylogenetic studies based on modern data on genetic variability of populations have allowed to reveal species complexes in Globodera pallida (Stone) Behrens and Nacobbus aberrans (Thorne) Thorne & Allen (sensu lato), including cryptic species. The main components of successful protection preventing a wide distribution of parasitic nematodes are quarantine measures, agricultural techniques, biological methods of protection and cultivation of resistant cultivars. Special attention in the review is paid to the breeding of potato cultivars with durable resistance to various nematode pathotypes, because the cultivation of such varieties is the most ecologically safe and economically advantageous way to prevent epiphytoties. Currently, significant progress has been made in the genetic protection of potato cultivars, especially against cyst-forming nematodes. The review provides data on sources of potato resistance to parasitic nematodes identified in collections of wild and cultivated species. Data on identified R-gens and QTL of resistance that have been introduced into breeding varieties using different methods and approaches are analyzed. The literature data on the study of structural and functional organization of genes for resistance to potato cyst nematodes are given. The results of molecular research on revealing the polymorphisms of loci involved in the control of resistance to cyst and gall nematodes, the development of molecular markers of certain genes and their use in marker-assisted selection for developing of new resistant cultivars, including those with group resistance, are considered.

Background. Predominant use of the H1 and Gro1-4 genes of resistance to golden nematode (PGN) in potato breeding requires widening the gene pool of resistance to this pathogen.Materials and methods. Thirty-four genotypes of wild potatoes from North and South Americas, 14 interspecific hybrids, and 10 Russian potato cultivars were studied for PGN resistance. Screening for resistance to PGN pathotype Ro1 and molecular screening for the presence of H1 and Gro1-4 gene markers were performed. Amplification products of the Gro1-4 gene marker were sequenced.Results. Only seven among the studied 34 potato genotypes (two of S. brachystotrichum (Bitt.) Rydb., four of S. lesteri Hawkes et Hjerting, and one of S. kurtzianum Bitt. et Wittm.) were susceptible to PGN, while the rest demonstrated high or medium resistance. Molecular screening for the presence of H1 and Gro1-4 gene markers allowed us to identify Gro1-4 in 13 South American genotypes of S. alandiae Cárd., S. × doddsii Corr., S. kurtzianum, S. leptophyes Bitt., and S. yungasense Hawkes. The remaining 14 genotypes may supposedly contain resistance genes non-identical to H1 or Gro1-4. Hybrids of S. tuberosum L. with medium-resistant wild accessions of S. kurtzianum, S. leptophyes, S. sparsipilum (Bitt.) Juz. et Buk., S. alandiae, and S. × doddsii inherited PGN resistance determined either by the Gro1-4 gene or genes non-identical to H1 or Gro1-4. Sequencing a fragment of the Gro1-4 gene showed that changes in the structure of this fragment in orthologous genes did not affect the feature of resistance to PGN pathotype Ro1.Conclusion. For the first time, sources of resistance to PGN were found among the North American species S. brachystotrichum (k-23201) and S. lesteri (k-24475). Among the wild South American Solanum spp., sources of resistance determined by genes different from H1 or Gro1-4 were identified. Resistant interspecific hybrids can serve as donors of the Gro1-4 resistance gene or new resistance genes.

Aim: to assess an opportunity of using infrared thermometry in predicting obstetric perineal tear.Materials and Methods. There was conducted a prospective analysis of 40 childbirth cases recorded in 2019-2020. There were stratified 2 study groups: Group 1 included 30 women without perineal injuries; Group 2 - 10 women with obstetric perineal rupture. Infrared thermometry in the posterior perineal junction projection was performed during the second period of labor at two timepoints: 1 - onset of the second labor period; 2 - descent of fetal head parietal tubercles.Results. The temperature difference between the first and second timepoints in Group 1 was 1.8 [1.71; 1.99] °C, in Group 2 - 2.7 [2.42; 2.82] °C (U = 54.000, p = 0.002). The rate of perineal temperature decline > 2.0 °C in Group 1 was 20 % (6/30), in Group 2 - 80 % (8/10) of cases (х2 = 11.868; p = 0.001). Such observation exhibited relatively high strength of relationship (V = 0.545). It is noteworthy that if perineal temperature decline at least by 2.0 °C for 2 minutes from descent of fetal head parietal tubercles to full birth of fetal head, the perineal rupture occurred in 100 % of cases (х2 = 7.556; p = 0.006), also featured with relatively high strength (V = 0.435).Conclusion. Perineal skin temperature decline at least by 2.0 °C for 2 minutes or more from descent of fetal head parietal tubercles may potentially be used as a criterion justifying episiotomy.