
V. N. Karazin Kharkiv National University
UniversityKharkiv, Kharkivs’ka Oblast’, Ukraine
Research output, citation impact, and the most-cited recent papers from V. N. Karazin Kharkiv National University (Ukraine). Aggregated across the NobleBlocks index of 300M+ scholarly works.
Top-cited papers from V. N. Karazin Kharkiv National University
It is commonly thought that human genetic diversity in non-African populations was shaped primarily by an out-of-Africa dispersal 50-100 thousand yr ago (kya). Here, we present a study of 456 geographically diverse high-coverage Y chromosome sequences, including 299 newly reported samples. Applying ancient DNA calibration, we date the Y-chromosomal most recent common ancestor (MRCA) in Africa at 254 (95% CI 192-307) kya and detect a cluster of major non-African founder haplogroups in a narrow time interval at 47-52 kya, consistent with a rapid initial colonization model of Eurasia and Oceania after the out-of-Africa bottleneck. In contrast to demographic reconstructions based on mtDNA, we infer a second strong bottleneck in Y-chromosome lineages dating to the last 10 ky. We hypothesize that this bottleneck is caused by cultural changes affecting variance of reproductive success among males.
and allied fusarioid genera (www.fusarium.org).
The results of studies on the regularities of structure formation and properties of high-entropy alloys prepared by different methods are analyzed and generalized. Specific features of the synthesis of nitride coatings based on multicomponent alloys are considered. Main physicomechanical properties of the coatings of different elemental composition deposited in different manner were compared. The bibliography includes 229 references.
Smart manufacturing is being shaped nowadays by two different paradigms: Industry 4.0 proclaims transition to digitalization and automation of processes while emerging Industry 5.0 emphasizes human centricity. This turn can be explained by unprecedented challenges being faced recently by societies, such as, global climate change, pandemics, hybrid and conventional warfare, refugee crises. Sustainable and resilient processes require humans to get back into the loop of organizational decision-making. In this paper, we argue that the most reasonable way to marry the two extremes of automation and value-based human-driven processes is to create an Industry 4.0 + Industry 5.0 hybrid, which inherits the most valuable features of both - efficiency of the Industry 4.0 processes and sustainability of the Industry 5.0 decisions. Digital cognitive clones twinning human decision-making behavior are represented as an enabling technology for the future hybrid and as an accelerator (as well as resilience enabler) of the convergence of the digital and human worlds.
Background On February 24, 2022, Russia invaded Ukraine provoking the most serious military conflict in Central Europe since 1945. By mid-May 2022, thousands of Ukrainian civilians have been killed or injured and millions relocated in the country or dispersed to other, mostly European, countries. To our knowledge, this is the first study on the impact of the war on the mental and emotional well-being of Ukrainian civilians—university students and personnel.Methods A snowball, non-probability sampling technique, was used for online survey data collection among students and personnel of 4 universities from May 5 to May 17, 2022. Four reliable instruments were used to collect information on the fear of war, resilience, burnout, and loneliness. Additional information was collected on substance use and eating behavior.Results Most respondents (97.8%) reported deterioration of their psycho-emotional status including depression (84.3%), exhaustion (86.7%), loneliness (51.8%), nervousness (84.4%), and anger (76.9%)—students more than personnel, females more than males. The use of substances (i.e., tobacco, alcohol, pain relievers, and sedatives) has increased as well as loneliness associated with fear, burnout and lower resilience. However, despite these conditions, 12.7% of the respondents have reported the war has not affected them.Conclusion Study findings are preliminary and limited in terms of time and location of data collection. However, results confirm the negative effects of war associated with mental health, fear, substance use, stress, loneliness, burnout, and other related conditions. Further research is needed to confirm the findings including the long-term impact of the war on the health and well-being of Ukrainian citizens.
ADVERTISEMENT RETURN TO ISSUEPREVReviewNEXTFullerenes in Liquid Media: An Unsettling Intrusion into the Solution ChemistryNikolay O. Mchedlov-Petrossyan*View Author Information Department of Physical Chemistry, Kharkov V. N. Karazin National University, Kharkov 61022, Ukraine*E-mail: [email protected]Cite this: Chem. Rev. 2013, 113, 7, 5149–5193Publication Date (Web):April 24, 2013Publication History Received14 December 2012Published online24 April 2013Published inissue 10 July 2013https://pubs.acs.org/doi/10.1021/cr3005026https://doi.org/10.1021/cr3005026review-articleACS PublicationsCopyright © 2013 American Chemical SocietyRequest reuse permissionsArticle Views3571Altmetric-Citations170LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Aromatic compounds,Carbon nanomaterials,Molecules,Nanospheres,Solvents Get e-Alerts
The Slavic branch of the Balto-Slavic sub-family of Indo-European languages underwent rapid divergence as a result of the spatial expansion of its speakers from Central-East Europe, in early medieval times. This expansion-mainly to East Europe and the northern Balkans-resulted in the incorporation of genetic components from numerous autochthonous populations into the Slavic gene pools. Here, we characterize genetic variation in all extant ethnic groups speaking Balto-Slavic languages by analyzing mitochondrial DNA (n = 6,876), Y-chromosomes (n = 6,079) and genome-wide SNP profiles (n = 296), within the context of other European populations. We also reassess the phylogeny of Slavic languages within the Balto-Slavic branch of Indo-European. We find that genetic distances among Balto-Slavic populations, based on autosomal and Y-chromosomal loci, show a high correlation (0.9) both with each other and with geography, but a slightly lower correlation (0.7) with mitochondrial DNA and linguistic affiliation. The data suggest that genetic diversity of the present-day Slavs was predominantly shaped in situ, and we detect two different substrata: 'central-east European' for West and East Slavs, and 'south-east European' for South Slavs. A pattern of distribution of segments identical by descent between groups of East-West and South Slavs suggests shared ancestry or a modest gene flow between those two groups, which might derive from the historic spread of Slavic people.
A new, non-polarizable force field model (FFM) for imidazolium-based, room-temperature ionic liquids (RTILs), 1-ethyl-3-methyl-imidazolium tetrafluoroborate and 1-butyl-3-methyl-imidazolium tetrafluoroborate, has been developed. Modifying the FFM originally designed by Liu et al. (J. Phys. Chem. B, 2004, 108, 12978-12989), the electrostatic charges on interacting sites are refined according to partial charges calculated by explicit-ion density functional theory. The refined FFM reproduces experimental heats of vaporization, diffusion coefficients, ionic conductivities, and shear viscosities of RTILs, which is a significant improvement over the original model (Zh. Liu, Sh. Huang and W. Wang, J. Phys. Chem. B, 2004, 108, 12978-12989). The advantages of the proposed procedure include clarity, simplicity, and flexibility. Expanding the functionality of our FFM conveniently only requires modification of the electrostatic charges. Our FFM can be extended to other classes of RTILs as well as condensed matter systems in which the ionic interaction requires an account of polarization effects.
Various approaches to creating multicomponent nanocomposite coatings of high and superhigh hardness (from ≈30 to 100–120 GPa) are reviewed with particular emphasis placed on mechanisms underlying the increase in hardness in thin (≤10 μm) coatings. The deposition technologies considered include magnetron sputtering, ion beam-assisted and vacuum arc depositions. A classification of hard and superhard coatings with high thermal stability is given. Possible applications of such nanostructured coatings are discussed and prospects for the field are outlined.
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> This paper adresses the behavior of the mutual information of correlated multiple-input multiple-output (MIMO) Rayleigh channels when the numbers of transmit and receive antennas converge to <emphasis><formula formulatype="inline"> <tex>$+\infty $</tex></formula></emphasis> at the same rate. Using a new and simple approach based on PoincarÉ–Nash inequality and on an integration by parts formula, it is rigorously established that the mutual information when properly centered and rescaled converges to a standard Gaussian random variable. Simple expressions for the centering and scaling parameters are provided. These results confirm previous evaluations based on the powerful but nonrigorous replica method. It is believed that the tools that are used in this paper are simple, robust, and of interest for the communications engineering community. </para>
Since the pioneering works by Landau, Zener, Stückelberg, and Majorana (LZSM), it has been known that driving a quantum two-level system results in tunneling between its states. Even though the interference between these transitions is known to be important, it is only recently that it became both accessible, controllable, and useful for manipulating a growing number of quantum systems. Here, we systematically study various aspects of LZSM physics and review the relevant literature, significantly expanding the review article in Ref. [504].
Novel species of fungi described in this study include those from various countries as follows: Antarctica , Cladosporium arenosum from marine sediment sand. Argentina , Kosmimatamyces alatophylus (incl. Kosmimatamyces gen. nov.) from soil. Australia , Aspergillus banksianus , Aspergillus kumbius , Aspergillus luteorubrus , Aspergillus malvicolor and Aspergillus nanangensis from soil, Erysiphe medicaginis from leaves of Medicago polymorpha , Hymenotorrendiella communis on leaf litter of Eucalyptus bicostata , Lactifluus albopicri and Lactifluus austropiperatus on soil, Macalpinomyces collinsiae on Eriachne benthamii , Marasmius vagus on soil, Microdochium dawsoniorum from leaves of Sporobolus natalensis , Neopestalotiopsis nebuloides from leaves of Sporobolus elongatus , Pestalotiopsis etonensis from leaves of Sporobolus jacquemontii , Phytophthora personensis from soil associated with dying Grevillea mccutcheonii. Brazil , Aspergillus oxumiae from soil, Calvatia baixaverdensis on soil, Geastrum calycicoriaceum on leaf litter, Greeneria kielmeyerae on leaf spots of Kielmeyera coriacea . Chile , Phytophthora aysenensis on collar rot and stem of Aristotelia chilensis . Croatia , Mollisia gibbospora on fallen branch of Fagus sylvatica . Czech Republic , Neosetophoma hnaniceana from Buxus sempervirens . Ecuador , Exophiala frigidotolerans from soil. Estonia , Elaphomyces bucholtzii in soil. France , Venturia paralias from leaves of Euphorbia paralias . India , Cortinarius balteatoindicus and Cortinarius ulkhagarhiensis on leaf litter. Indonesia , Hymenotorrendiella indonesiana on Eucalyptus urophylla leaf litter. Italy , Penicillium taurinense from indoor chestnut mill. Malaysia , Hemileucoglossum kelabitense on soil, Satchmopsis pini on dead needles of Pinus tecunumanii . Poland , Lecanicillium praecognitum on insects' frass. Portugal , Neodevriesia aestuarina from saline water. Republic of Korea , Gongronella namwonensis from freshwater. Russia , Candida pellucida from Exomias pellucidus , Heterocephalacria septentrionalis as endophyte from Cladonia rangiferina , Vishniacozyma phoenicis from dates fruit, Volvariella paludosa from swamp. Slovenia , Mallocybe crassivelata on soil. South Africa , Beltraniella podocarpi , Hamatocanthoscypha podocarpi , Coleophoma podocarpi and Nothoseiridium podocarpi (incl. Nothoseiridium gen. nov.)from leaves of Podocarpus latifolius , Gyrothrix encephalarti from leaves of Encephalartos sp., Paraphyton cutaneum from skin of human patient, Phacidiella alsophilae from leaves of Alsophila capensis , and Satchmopsis metrosideri on leaf litter of Metrosideros excelsa. Spain , Cladophialophora cabanerensis from soil, Cortinarius paezii on soil, Cylindrium magnoliae from leaves of Magnolia grandiflora , Trichophoma cylindrospora (incl. Trichophoma gen. nov.) from plant debris, Tuber alcaracense in calcareus soil, Tuber buendiae in calcareus soil. Thailand , Annulohypoxylon spougei on corticated wood, Poaceascoma filiforme from leaves of unknown Poaceae. UK , Dendrostoma luteum on branch lesions of Castanea sativa , Ypsilina buttingtonensis from heartwood of Quercus sp. Ukraine , Myrmecridium phragmiticola from leaves of Phragmites australis. USA , Absidia pararepens from air, Juncomyces californiensis (incl. Juncomyces gen. nov.) from leaves of Juncus effusus , Montagnula cylindrospora from a human skin sample, Muriphila oklahomaensis (incl. Muriphila gen. nov.)on outside wall of alcohol distillery, Neofabraea eucalyptorum from leaves of Eucalyptus macrandra , Diabolocovidia claustri (incl. Diabolocovidia gen. nov.)from leaves of Serenoa repens , Paecilomyces penicilliformis from air, Pseudopezicula betulae from leaves of leaf spots of Populus tremuloides . Vietnam , Diaporthe durionigena on branches of Durio zibethinus and Roridomyces pseudoirritans on rotten wood. Morphological and culture characteristics are supported by DNA barcodes.
The European medicinal leech is one of vanishingly few animal species with direct application in modern medicine. In addition to the therapeutic potential held by many protease inhibitors purified from leech saliva, and notwithstanding the historical association with quackery, Hirudo medicinalis has been approved by the United States Food and Drug Administration as a prescription medical device. Accurate annotation of bioactive compounds relies on precise species determination. Interpretations of developmental and neurophysiological characteristics also presuppose uniformity within a model species used in laboratory settings. Here, we show, with mitochondrial sequences and nuclear microsatellites, that there are at least three species of European medicinal leech, and that leeches marketed as H. medicinalis are actually Hirudo verbana. Beyond the obvious need for reconsideration of decades of biomedical research on this widely used model organism, these findings impact regulatory statutes and raise concerns for the conservation status of European medicinal leeches.
Breast cancer is the most common cancer in women and the most common cause of death in working-age women. According to the results of immunohistochemical studies, 10-20% of cases revealed a triple-negative type of breast cancer. This subtype is characterized by significant proliferative activity and growth rate, aggressive clinical course, and early metastasis. This leads to a suspicious prognosis and, accordingly, encourages an increase of surgical treatment radicalism and aggressive systemic treatment. This review briefly analyzes existing treatment strategies for triple-negative breast cancer with a focus on surgical treatment. Surgical treatment is an integral part of complex therapy. Currently, the attention of researchers is focused not only on the radicalism of the operation, ensuring long-term survival, but also on achieving a good cosmetic result that determines the quality of life of patients. In this aspect, organ-preserving and prosthetic methods of operations are promising, the feasibility and effectiveness of which are being discussed. The relevance of choosing the optimal method of operation is evidenced by the lack of generally accepted approaches based on informative markers for the prognosis of the course of the disease. Therefore, the choice of the optimal method of surgical treatment taking into account the individual characteristics of the patient and the tumor, indications for chemotherapy, and radiation therapy remains an unresolved issue and requires further research.
Flow field designs for the bipolar plates of the proton exchange membrane fuel cell are reviewed; including the serpentine, parallel, interdigitated, mesh type or their mixtures, furthermore 2D circular and 3D tubular geometries, porous, fractal and biomimetic flow fields. The advantages / disadvantages and tendencies from field optimizations are discussed. The performance of each flow field design is compared to the conventional serpentine flow field. Good flow field plates give uniform gas distributions, low pressure drop for transport and sufficient rib area to provide high electronic conductivity. A good field should also prevent water condensation, remove water efficiently, and provide sufficiently high moisture content in the membrane. The demands on design are sometimes contradictory. Future work should aim for a flow field geometry and topology that produces uniform gas delivery at a low pressure-drop, and at the same time has an optimal channel shape for better water removal. It is concluded that for an area-filling gas distributor, the developments should aim to find a flow field in accordance with minimum entropy production, making an emphasis on multi-criteria optimization methods.
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Context. N-methylformamide, CH 3 NHCHO, may be an important molecule for interstellar pre-biotic chemistry because it contains a peptide bond, which in terrestrial chemistry is responsible for linking amino acids in proteins. The rotational spectrum of the most stable trans conformer of N-methylformamide is complicated by strong torsion-rotation interaction due to the low barrier of the methyl torsion. For this reason, the theoretical description of the rotational spectrum of the trans conformer has, up to now, not been accurate enough to provide a firm basis for its interstellar detection. Aims. In this context, as a prerequisite for a successful interstellar detection, our goal is to improve the characterization of the rotational spectrum of N-methylformamide. Methods. We use two absorption spectrometers in Kharkiv and Lille to measure the rotational spectra over the frequency range 45-630 GHz. The analysis is carried out using the Rho-axis method and the RAM36 code. We search for N-methylformamide toward the hot molecular core Sagittarius (Sgr) B2(N2) using a spectral line survey carried out with the Atacama Large Millimeter/submillimeter Array (ALMA). The astronomical spectra are analyzed under the assumption of local thermodynamic equilibrium. The astronomical results are put into a broader astrochemical context with the help of a gas-grain chemical kinetics model.
We demonstrate how to design all-dielectric metasurfaces with a strong axial toroidal response by arranging two types of nanodisks into asymmetric quadrumer clusters. This toroidal response is related to the existence of the trapped (dark) mode that appears due to a symmetry breaking in the cluster. We uncover a correlation between the existence of the toroidal response and asymmetry in the metasurface geometries, which originates from different diameters of nanodisks or notches introduced into nanodisks. Because of the unique field configuration of the toroidal mode, the proposed metasurface could serve as a platform for efficient light–matter interaction for enhanced absorption, nonlinear response, and sensing.
Silver nanoparticles (AgNPs) possess unique physicochemical properties, which are different from those of matter of the same chemical composition on a larger scale. These features open up the opportunity for their use in many promising chemical and biomedical applications. In this study we have developed an atomistic model for molecular dynamics (MD) simulations of AgNP coated by poly(N-vinyl-2-pyrrolidone) (PVP) oligomers. We focus on identifying the relative length of PVP oligomers, enabling effective protecting of a crystalline silver core of 4.5 nm diameter from water contacts. Three different PVP-coated AgNP systems have been compared: (i) a nanoparticle coated by a mixture of short-chain PVP oligomers of the varying size and (ii,iii) the silver core wrapped by a single, long-chain PVP polymer with the number of monomers equal to 816 and 1440, respectively. We have validated the MD models of the PVP–AgNPs using a series of MD simulations reproducing adsorption, wrapping, and coating of PVP around a silver core either as short PVP oligomers or as a single-chain, long polymer of a varying length. Our simulations predict that the saturated coating of PVP around the silver core of the given diameter can occur when the polymer chain length approaches 2600–2800 units.
We argue that the possibility of having infinite energy in the center-of-mass frame of colliding particles is a generic property of rotating black holes. We suggest a general model--independent derivation valid for dirty black holes. The earlier observations for the Kerr or Kerr-Newman metrics are confirmed and generalized.