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Spermatogenesis starts with the onset of puberty within the seminiferous epithelium of the testes. It is a complex process under intricate control of the endocrine system. Physiological regulations by steroid hormones in general and by estrogens in particular are due to their chemical nature prone to be disrupted by exogenous factors acting as endocrine disruptors (EDs). 17α-Ethynylestradiol (EE2) is an environmental pollutant with a confirmed ED activity and a well-known effect on spermatogenesis and chromatin remodeling in haploid germ cells. The aim of our study was to assess possible effects of two doses (2.5ng/ml; 2.5 μg/ml) of EE2 on both histone-to-protamine exchange and epigenetic profiles during spermatogenesis performing a multi/transgenerational study in mice. Our results demonstrated an impaired histone-to-protamine exchange with a significantly higher histone retention in sperm nuclei of exposed animals, when this process was accompanied by the changes of histone post-translational modifications (PTMs) abundancies with a prominent effect on H3K9Ac and partial changes in protamine 1 promoter methylation status. Furthermore, individual changes in molecular phenotypes were partially transmitted to subsequent generations, when no direct trans-generational effect was observed. Finally, the uncovered specific localization of the histone retention in sperm nuclei and their specific PTMs profile after EE2 exposure may indicate an estrogenic effect on sperm motility and early embryonic development via epigenetic mechanisms. [ABSTRACT FROM AUTHOR]

When processed in solid or liquid medium, tuberculosis patient samples yield different proportions of a heterogenous bacterial community over the duration of treatment. We aimed to derive a relationship between methodologies for bacterial load determination and assess the effect of the growth phase of the parent culture and its exposure to stress on the results. Mycobacterium tuberculosis H37Rv was grown with and without antibiotic (isoniazid or rifampicin) and sampled on day 0, 3, 11 and 21 of growth in broth culture. The bacterial load was estimated by colony counts and the BD BACTEC MGIT system. Linear and nonlinear mixed-effects models were used to describe the relationship between time-to-positivity (TTP) and time-to-growth (TTG) versus colony forming units (CFU), and growth units (GU) versus incubation time in MGIT. For samples with the same CFU, antibiotic-treated and stationary phase cells had a shorter TTP than antibiotic-free controls and early-logarithmic phase cells, respectively. Similarly, stationary phase samples reached higher GUs and had shorter TTG than early-log phase ones. This suggests that there is a population of bacterial cells that can be differentially recovered in liquid medium, giving us insight into the physiological states of the original culture, aiding the interpretation of clinical trial outputs. [ABSTRACT FROM AUTHOR]

A technology is developed for manufacturing planar microfluidic chips (MFCs) based on Silgard 8040, encompassing template fabrication, mold production, sealing, and adsorbent filling. These MFCs, filled with a Porapak-Q adsorbent, facilitate sample preparation and calibration under uniform conditions, integrating both sample collection and preconcentration stages. Experimental investigations have identified optimal conditions for acetone preconcentration using Silgard 8040-based MFCs, achieving a maximum concentration factor of 43 at adsorption temperature (Tads) of 0°C, desorption temperature (Tdes) of 70°C, adsorption volume (Vads) of 45 mL, and desorption time (tdes) of 1 s. The feasibility of using MFCs for sample collection and preparation, taking into account sample storage time, has been evaluated. The procedure maintains accuracy within 6–10% over 8 h without a necessity for additional drying of the collected samples from exhaled air. [ABSTRACT FROM AUTHOR]

Distrust in voting is not a rare phenomenon even in developed countries. Electronic voting (e-voting), however, appeared as an alternative, but is still not practiced on a large scale. This is due to the fact that despite the huge number of articles it is not yet possible to completely ensure security, privacy and verifiability. It is hard to create a system or a protocol fulfilling all requirements, especially unconditionally. Designing effective voting systems is challenging because these aspects often conflict with each other. There are issues that need to be resolved. For example, one of such challenges is trying to ensure identification and keep votes private while still being able to verify them. There are quite a few cryptographic schemes which fulfill wide requirements for online elections. Their only disadvantage is inconvenience: they use sophisticated cryptographic tools that make them hard to implement and require expertise in various fields. In this paper we suggest a new approach that ensures this requirements without complex cryptographic methods. First, we propose a novel architecture for an internet voting system that incorporates steganography techniques to enhance the security of the system. In the proposed architecture steganography is used to hide the votes within the data packets transmitted between the storage, that keeps all the votes, and the counting server. The next proposed novelty is the solution of the privacy – verifiability problem using only face recognition, properties of image entropy and hash functions. The advantage of this system is ease of use without loss of security. [ABSTRACT FROM AUTHOR]

The work describes a set of polynomials that have less power than a given polynomial from a certain class. [ABSTRACT FROM AUTHOR]

The paper analyses global online labour platforms (OLPs) through the lens of the Expansive‐Restrictive Learning Environments framework. The framework articulates a set of structural factors that enable or constrain workplace learning and development. The paper draws on multistakeholder, mixed‐method empirical data to illustrate how OLPs are emerging as learning environments, where new and reconfigured skills, learning practices, and new forms of learning support emerge in response to the radically distributed and fragmented nature of this work. Against portrayals of OLPs as places of deskilling work devoid of learning opportunities, the paper contributes a more nuanced understanding of the duality of OLPs as simultaneously restrictive and expansive. Three dualities of OLPs emerge from the study: (i) their espoused vision restricts organisational support for workforce development, yet stimulates self‐directed learning; (ii) their enacted workplace curriculum is patchy and opaque, yet offers novel structural features supporting learning and development; (iii) workplace learning practices in OLPs are autonomous, yet not atomised. The paper illustrates how structure and individual agency interact in OLPs to create and configure learning opportunities for workers and informs practitioners about the current learning and development features and practices in OLPs. [ABSTRACT FROM AUTHOR]

This work is devoted to assessing the features of the distribution of spatiotemporal changes in the characteristics of the minimum 30-day winter flow of rivers in the basin of Lake Sevan. The problem of spatiotemporal changes in the minimum river flow is especially relevant for regions with insufficient and unstable moisture, like the basin of Lake Sevan, most of which is located within the steppe zone. The purpose of this work is to summarize modern ideas about the impact of climate change on the characteristics of the minimum 30-day winter river flow based on the authors' own research, to analyze and evaluate the spatiotemporal variability of long-term fluctuations, and to identify nonstationarity in the series of minimum winter flow. The characteristics of the minimum flow have been determined, their spatiotemporal changes have been studied, and the dates of violations of homogeneity in the series of long-term runoff observations have been discovered. Using statistical parameters and difference integral curves, we assessed the representativeness of time series of minimum 30-day winter water flows at 12 sites during the period of instrumental observations. Nonstationarity in the series of minimum winter runoff in the basin of Lake Sevan has been revealed, and the dates for changes in stationary regimes have been determined. For most of the watersheds analyzed, the changes are statistically significant. Maps of the date of violation of the stationarity of the series under consideration based on information up to 2021 are presented, including a map of the distribution of the module of the minimum 30-day runoff for the winter period and maps on the nature of changes in the minimum 30-day winter flow. It is shown that changes in the minimum 30-day winter flow have a multidirectional nature, but mainly for the minimum 30-day winter flow, on average, over the territory of the lake basin. In recent decades, Lake Sevan has shown an increasing trend associated with rising air and soil surface temperatures. For some of the watersheds analyzed, the changes are statistically insignificant. On the territory of the Vardenis, Lichk, and Bakhtak river basins, on average, the minimum 30-day winter flow decreases by 20–30%, which will lead to an increase in environmental risk, requiring the adoption of appropriate measures. The obtained statistical materials will serve as the basis for scientific generalizations of research on the territory under consideration and can also be used for practical purposes in hydraulic engineering design and assessment of natural hazards and in making appropriate preventive decisions. [ABSTRACT FROM AUTHOR]

The title compound, poly [bis(β-alaninium) [[dibromidoplumbate]-di-μ-dibromido]] {(C2H8NO2)2[PbBr4]}n or (β-AlaH)2PbBr4, crystallizes in the monoclinic space group P21/n. The (PbBr4)2− anion is located on a general position and has a two-dimensional polymeric structure. The Pb center is holodirected. The supramolecular network is mainly based on O—H⋯Br, N—H⋯Br and N—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

The crystal structure of hexaglycinium tetra-μ-iodido-octaiodidotriplumbate, (C2H6NO2)6[Pb3I12] or (GlyH)6[Pb3I12], is reported. The compound crystallizes in the triclinic space group P1. The [Pb3I12]6− anion is discrete and located around a special position: the central Pb ion located on the inversion center is holodirected, while the other two are hemidirected. The supramolecular nature is mainly based on C—H⋯I, N—H⋯I, O—H⋯I and N—H⋯O hydrogen bonds. Dimeric cations of type (A+⋯A+) for the amino acid glycine are observed for the first time. [ABSTRACT FROM AUTHOR]

The perpetration of the Armenian Genocide did not originate as the direct implementation of ideological convictions; rather, stemmed from an amalgamation of certain theories adjusted to political and economic developments in the Ottoman Empire in tandem with the desire to transform a multi-ethnic and multi-religious empire into a Turkish nation-state. Within this nation-building project, the Young Turk's government chose to exterminate the indigenous Armenian minority, using forced transfer and the assimilation of children and young women into Turkish society as one of the methods of destroying the Armenian community. This fits well into the overall Turkish nationalist ideology, as women and children were deemed as not having a transmutable ethnic identity: while a woman's identity could be discounted, the identity of children could be reprogrammed by stripping them of their Armenian identity and imposing a new identity through change of personal data, religious conversion and education. Building on existing research, this article first presents the ideological foundations of Turkish nation-building and the implementation of the Armenian Genocide to achieve this end, focusing on the forcible transfer and assimilation which selected Armenian children endured. Informed by both published and unpublished memories of transferred children, the second part of the article reconstructs the actual process and methods of Turkification used in several state-run orphanages while also presenting the resistance of Armenian children to these efforts. This article expands the number of known state orphanages and widens the geographic scope of where Turkification practices took place, thus substantiating a general assimilation policy of the CUP towards some selected Armenian children and arguing that forced transfer and Turkification were used as a method of destroying the Armenian community. It also enters new testimonies into public circulation that help to better understand the role of forced transfer during the Armenian Genocide and its implications on the survivors. [ABSTRACT FROM AUTHOR]

The paper discusses the results of the electrosynthesis of metal–polymer nanocomposites of silver and coatings on pure iron and steel electrodes by combining the process of electropolymerization of 1-vinyl-1,2,4-triazole (VT) with N-vinyl-caprolactam (VC) and cathodic precipitation of metals. During the electrolysis of aqueous and water–ethanol solutions of VT with VC at various ratios in the presence of AgNO3, metal nanocomposites and coatings are formed on purely iron and steel electrodes. The structure and composition of the synthesized metal nanocomposites were confirmed by various physicochemical methods, such as electron and IR spectroscopic, X-ray phase and thermogravimetric, elemental analyses, as well as by transmission electron microscopy. In the electronic spectra of nanocomposites, absorption bands appear with a maximum at 405–421 nm, which is typical for systems with zero-valent silver. The IR spectra show that the matrix structure hardly changes during the formation of nanocomposites and coatings. At high current densities (j ≥ 10 mA/sm2), nanocomposite films are formed on the electrode surface. The silver content in nanocomposites is 0–9%, which leads to an increase in the viscosity of nanocomposite solutions compared to solutions of the initial copolymers. Increasing the silver content above 8% will lead first to a partial and then to a complete loss of solubility. According to the data of transmission electron macroscopy, the synthesized polymer nanocomposites consist of isolated silver nanoparticles, predominantly spherical in shape, uniformly distributed in the bulk of the polymer matrix. The size dispersion of nanoparticles depends on the silver content in the nanoparticles. The thermal decomposition of metal nanocomposites occurs in stages. [ABSTRACT FROM AUTHOR]

Background Vascular graft infection (VGI) is a serious complication after implantation of arterial vascular grafts. Optimal surgical and pathogen-specific antimicrobial treatment regimens for VGI are largely unknown. We evaluated patients with arterial VGI according to onset, location, microbiological and imaging characteristics, and surgical and antimicrobial treatment and performed an outcome evaluation. Methods Consecutive patients with VGI treated in 2 hospitals from 2010 through 2020 were retrospectively analyzed. Uniform definition criteria and standardized outcome evaluation were applied. Logistic regression was used for multiple analysis; survival analysis was performed with Kaplan-Meier analysis and a log-rank test. Results Seventy-eight patients with VGI were included: 30 early-onset cases (<8 weeks after graft implantation) and 48 late-onset cases, involving 49 aortic and 29 peripheral grafts. The median time from initial implantation to diagnosis of VGI was significantly longer in aortic than peripheral VGIs (363 vs 56 days, P =.018). Late-onset VGI (odds ratio [OR], 7.3; P =.005) and the presence of surgical site infection/complication (OR, 8.21; P =.006) were independent risk factors for treatment failure. Surgical site infection/complication was associated with a higher risk for early-onset VGI (OR, 3.13; P =.040). Longer infection-free survival was observed in cases where the infected graft was surgically removed (P =.037). Conclusions This study underlines the importance of timely diagnosis of VGI and preventing surgical site infections/complications at graft implantation. It highlights the complexity of infection eradication, especially for late-onset infections, and the importance of adequate antimicrobial and surgical treatment. [ABSTRACT FROM AUTHOR]

The alkylation of 2-(4-fluorophenyl)- and 2-[3-(trifluoromethyl)phenyl]acetonitriles with 1,4-di-bromo-butane gave 1-(substituted phenyl)cyclopentane-1-carbonitriles which were hydrolyzed to the corre-sponding carboxylic acids by the action of potassium hydroxide in ethylene glycol. The resulting acids were converted to acid chlorides, and the latter reacted with N,N-dialkylaminoalkylamines, as well as with N,N-di-alkylaminoalkanols, to produce new amino amide and amino ester derivatives of 1-(4-fluorophenyl)- and 1-[3-(trifluoromethyl)phenyl]cyclopentane-1-carboxylic acids, which were characterized as hydrochlorides. The synthesized compounds were evaluated for their antiarrhythmic and anticonvulsant activities. [ABSTRACT FROM AUTHOR]

The possibility of short-term and long-term forecasting of water levels, including those associated with dangerous hydrological phenomena on the Marmarik River, using various probabilistic approaches, including regression dependencies, an integrated moving average autoregression model, and multilayer perceptron models, is considered. To evaluate the effectiveness of prognostic methods, the statistical parameters of a random process are calculated, while recommendations are given using the classical criteria for the effectiveness of issued forecasts. For long-term forecasting, the expediency of using the integrated moving average autoregression model was assessed, while it is noted that these models in the classical representation are not applicable due to time gaps, and therefore it is recommended to focus on the mathematical expectation of a random process. For short-term forecasting one or two steps ahead, the method of training artificial neural networks was used. The analysis carried out in the work revealed that in the case of short-term forecasting of water levels for one period in advance (12 h), it is most expedient to focus on the value of the water level attributable to the date of issue of the forecast, the standard error of such a forecast is 5 cm. For a 24-h water level forecast forward, it is expedient to develop neural network forecasting models, taking into account the development of the situation on Gomraget-Meghradzor. A further increase in the quality of the outputs is possible when using data for a longer observation period and a whole year. At the same time, as an alternative to neural network forecasting models, physical and mathematical (hydraulic) models of the formation of water levels can be used. [ABSTRACT FROM AUTHOR]

The article presents the publication of an unknown decree of Nādir Šāh issued in December 1742/January 1743 at the request of the Armenian merchants of Agulis. It examines the taxes levied from the merchants and the ways of tax extortion and excesses committed by Nādir Šāh's administration in that period. The article contains a short review of the historical background of the document, the economic situation in the Nādir Šāh's empire including Agulis. [ABSTRACT FROM AUTHOR]

The development of sustainable and environmentally friendly industrial processes is becoming very crucial and demanding for the rapid implementation of innovative bio-based technologies. Natural extreme environments harbor the potential for discovering and utilizing highly specific and efficient biocatalysts that are adapted to harsh conditions. This review focuses on extremophilic microorganisms and their enzymes (extremozymes) from various hot springs, shallow marine vents, and other geothermal habitats in Europe and the Caucasus region. These hot environments have been partially investigated and analyzed for microbial diversity and enzymology. Hotspots like Iceland, Italy, and the Azores harbor unique microorganisms, including bacteria and archaea. The latest results demonstrate a great potential for the discovery of new microbial species and unique enzymes that can be explored for the development of Circular Bioeconomy. Different screening approaches have been used to discover enzymes that are active at extremes of temperature (up 120 °C), pH (0.1 to 11), high salt concentration (up to 30%) as well as activity in the presence of solvents (up to 99%). The majority of published enzymes were revealed from bacterial or archaeal isolates by traditional activity-based screening techniques. However, the latest developments in molecular biology, bioinformatics, and genomics have revolutionized life science technologies. Post-genomic era has contributed to the discovery of millions of sequences coding for a huge number of biocatalysts. Both strategies, activity- and sequence-based screening approaches, are complementary and contribute to the discovery of unique enzymes that have not been extensively utilized so far. [ABSTRACT FROM AUTHOR]

AGRICULTURE productivity is severely hampered by salinity stress in many parts of the world, including the Ararat Plain in Armenia. The need for food security is growing worldwide, and new strategies are essential to meet this challenge. In the context of the Ararat Plain, this paper examines the potential utility and promising role of biogenic nanoparticles (NPs) and biochar in reducing salinity stress, boosting crop resilience, and guaranteeing sustainable food production. This paper involves the mechanisms underlying salinity stress, as well as the properties and synthesis of biogenic nanoparticles and biochar, and their applications in increasing plant salinity tolerance. The potential application of biogenic nanoparticles and biochar to mitigate the adverse effects of salinity on crops, soil, and water resources has been recently illustrated by several case studies and research findings. Additionally, we go over the safety issues, environmental implications, and potential applications of biogenic nanoparticles and biochar in sustainable agriculture on the Ararat Plain and elsewhere. This paper advances our knowledge of innovative strategies for addressing salinity stress and improving food security in areas with comparable problems. [ABSTRACT FROM AUTHOR]

The ongoing development of carbon dots (CDs) for different applications calls for researching novel methods for their synthesis and surface functionalization. For the fabrication of photonic devices, apart from the obvious requirement of bright luminescence, CDs also should be soluble in the non-polar solvents used for the ink-printing of their functional layers. Herein, we introduce amphiphilic CDs synthesized from a mixture of benzoic acid and ethylenediamine in acetylacetone, which satisfy both of the abovementioned requirements. These CDs are quasi-spherical nanoparticles that are 20–50 nm in size, with aliphatic, carbonyl, amide, imine, and carbamate groups at the surface. This wide spectrum of surface groups renders them amphiphilic and soluble in a variety of substances, such as toluene, chloroform, alcohol, and water, with relative polarity ranging from 0.002 to 1. By variation of the molar ratio of benzoic acid and ethylenediamine, the highest quantum yield reported so far of 36% in isopropanol is achieved for the amphiphilic CDs. As a demonstration of the use of developed amphiphilic CDs in LEDs, green-emitting charge-injection devices were fabricated with a broad emission band centered at 515 nm, maximal luminance of 1716 cd m−2, and CCT of 5627 K. These LEDs are the first ones based on amphiphilic CDs. Furthermore, these CDs can be used as luminescent inks and as an active material for solar concentrators. [ABSTRACT FROM AUTHOR]

Metal halide perovskite nanoplatelets (NPls) have recently joined a rich family of 2D semiconductor nanomaterials. Quantum and dielectric confinement in these nanostructures endow them with useful optical properties, which include, but are not limited to, high linear and nonlinear absorption coefficients, narrow and tunable emission bands, and high photoluminescence quantum yield. These characteristics render perovskite NPls promising for applications in lighting, photodetection, nonlinear optics, and photocatalysis. Doping is a universal approach for tuning optical and electronic properties of semiconductor materials, and the B‐site doping of perovskite NPls allows the further improvement and adjustment on demand of the above‐mentioned optical properties and may result in the appearance of fundamentally new behavior through embedding optically active dopants. In this mini‐review, the basic knowledge about perovskite NPls is shortly summarized in terms of their colloidal synthesis, and then the B‐site doping of perovskite NPls is considered in terms of the existing approaches (in situ and post‐synthetic doping) and its effect on the optical characteristics (doping with self‐emitting ions such as Mn2+ and rare‐earth elements; consequences for the nonlinear optical response). [ABSTRACT FROM AUTHOR]

The most important parameter determining the efficiency of carbon dots as light absorbers in photocatalytic systems is the strength of their binding to the catalyst. It is rather difficult to estimate the contribution of this parameter of carbon dots to the overall efficiency of the photocatalytic system, since the post-synthetic modification of the surface of carbon dots is accompanied by a significant change in their optical and structural properties. In this work, we performed post-synthetic modification of the surface of carbon dots based on citric acid by amination with ethylenediamine molecules by activating the carboxyl groups of carbon dots with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide molecules. The use of this amination approach made it possible to change the charge of carbon dots without changing their main optical and structural properties, which can be further used to assess the contribution of the strength of their binding with Dubois-type molecular catalysts to the overall efficiency of the photocatalytic system. [ABSTRACT FROM AUTHOR]

Cubic boron nitride (c-BN) is an ultrawide band gap, superhard material with significant potential for applications under extreme temperatures and pressures. Nevertheless, two major challenges hinder its practical utilization in technology: (i) the difficulty in producing high-quality c-BN films, and (ii) the challenge of effectively n- and p-doping its matrix. This theoretical study focuses on investigating the solubility limits of silicon (Si) and carbon (C) in the c-BN and wurtzite BN (WZ–BN) on the basis of the strictly regular solution approximation. These elements are key candidates as n-type dopants in BN, addressing a critical concern in the realization of c-BN based electronics. The calculated Gibbs free energies of binary mixtures within the temperature range of 800–3000 K indicate that the presence of unstable regions, and consequently, miscibility gaps, are a prevalent characteristic of this system. The analysis reveals that the immiscibility gap is influenced not only by temperature, but also by the crystallographic structure. The calculated results of Si solubility limit in BN–Si binary system are in a good agreement with the latest experimental results. The findings presented here are applicable to the fabrication of multicomponent bulk crystals, epitaxial thin films, and nanostructures based on BN–Si–C solid solutions. [ABSTRACT FROM AUTHOR]

Formulation of the problem. Studies of trends in the minimum 30-day winter runoff of rivers flowing out of the lake. Sevan has acquired great practical importance and significant interest from the point of view of calculating the ecological flow, due to the increased use of water resources for various types of economic activities, in particular, in connection with the development of the economy, hydropower, irrigation, population growth and improving living standards. Calculations of the minimum runoff are especially relevant in relation to solving the problems of water supply to settlements, industrial and agricultural enterprises, as well as assessment of irrigation norms of agricultural plots. The aim of the work. Analysis and assessment of trends in the minimum 30-day winter runoff of rivers flowing out of the lake Sevan. Methods. The following methods were used in the work: mathematical-statistical, correlation, cartographic, extrapolation, interpolation, spatial analysis, analogy. Results. During the research, the characteristics of the winter minimum 30-day water consumption for the entire observation period were calculated for hydrological posts on the rivers of the lake Sevan basin, which have a number of observations for 40 years or more. Supply curves are constructed, the values of the winter minimum 30-day runoff are estimated, with security of 90, 95 and 99.5% for 12 sites. The values of the flow rates, its coefficients of variation (Cv) and asymmetry (Cs) are determined. The analysis of the temporal distribution of the studied hydrological characteristics was carried out, the coefficients of the linear trend of the minimum 30-day winter runoff were determined. Close correlations have been obtained between the values of the average monthly minimum water consumption and the minimum 30-day winter water consumption. These dependencies can be used to predict the minimum 30-day winter water consumption of the rivers of the territory under consideration. It is established that for the rivers of the lake Sevan basin is characterized by synchronicity of fluctuations in annual and winter runoff. It was revealed that most of the rivers flowing into the lake Sevan (by more than 58% of posts), there is an increase in the amount of winter runoff, i.e. a positive trend in its change. Based on the results obtained, a distribution map of the linear trend coefficients of the minimum 30-day winter runoff in m3 /sec / 10 years with an observation period from december to march was constructed. [ABSTRACT FROM AUTHOR]

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The alkylation of 2-(1,3-benzodioxol-5-yl)acetonitrile with bis(2-chloroethyl) ether gave 4-(1,3-ben-zo-dioxol-5-yl)-tetrahydro-2H-pyran-4-carbonitrile which was reduced with lithium tetrahydroaluminate to [4-(1,3-benzodioxol-5-yl)-tetrahydro-2H-pyran-4-yl]methanamine. The latter reacted with aryloxymethyl-oxiranes to produce the corresponding 1-(aryloxy)-3-({[4-(1,3-benzodioxol-5-yl)-tetrahydro-2H-pyran-4-yl]-methyl}amino)propan-2-ols. The reaction of the same amine with chloroacetyl chloride afforded N-{[4-(1,3-ben-zodioxol-5-yl)-tetrahydro-2H-pyran-4-yl]methyl}-2-chloroacetamide which was treated with secondary amines and hetarenethiols to obtain N-{[4-(1,3-benzodioxol-5-yl)-tetrahydro-2H-pyran-4-yl]methyl}-substi-tuted 2-amino- and 2-sulfanylacetamide derivatives. The synthesized compounds were evaluated for their antioxidant activity. [ABSTRACT FROM AUTHOR]

The article was dedicated to a study on brief overview of noise pollution in Ijevan Town of Armenia. The noise generated by the traffic flow on the section of the Noyemberyan-Yerevan highway adjacent to the Ijevan subtropical arboretum was calculated and measured. The equivalent noise level from the traffic flow at a distance of 7.5 m from the centre of the nearest traffic lane was estimated at 70.7-72.3 dB, and the average measured noise level was 73-75 dB. The average measured noise level of the Ijevan Subtropical Arboretum near the Aghstev river was 50 dB. [ABSTRACT FROM AUTHOR]

The sorption properties of composite sorbents obtained on the basis of clay materials by the sorption of a number of metals were studied by ICP-MS and SEM-XRF methods. Organo-mineral adsorbent was obtained on the basis of diatomite and bentanite and paper pulp. The diatomite of the Jradzor deposit and the bentonite of the Sarigyukh deposit (Armenia) were used. Diatomite serves as a structure-forming component and ensures mass transfer due to its high porosity (V = 2.0 cm3/g) and large pore sizes (150-200 nm). Bentonite provides the plasticity of the mixture when receiving the adsorbent. In addition, as its structural features and treatment with phosphoric acid, bentonite acquires functional groups, or during such treatment, vacancies are formed in the structure of bentonite, which become adsorption centres of the resulting sorbents. Let's call this phenomenon "hole sorption". The inorganic component DB-12P, in addition to being an independent adsorbent, serves as a porous carrier for the organic component (functionalised cellulose). The organic component, in turn, becomes a carrier of functional groups (in this case, orthophosphoric acid residues), i.e. the fixation of functional groups on the surface of the inorganic porous carrier is carried out with the help of cellulose. Filter paper (cellulose content about 95 wt.%) treated with phosphonic acid was used as an organic component. The object of study was a synthetic solution containing cations of heavy metals, radionuclides and other elements. [ABSTRACT FROM AUTHOR]

The present study is the first in-depth research evaluating the genetic diversity and potential resistance of Armenian wild grapes utilizing DNA-based markers to understand the genetic signature of this unexplored germplasm. In the proposed research, five geographical regions with known viticultural history were explored. A total of 148 unique wild genotypes were collected and included in the study with 48 wild individuals previously collected as seed. A total of 24 nSSR markers were utilized to establish a fingerprint database to infer information on the population genetic diversity and structure. Three nSSR markers linked to the Ren1 locus were analyzed to identify potential resistance against powdery mildew. According to molecular fingerprinting data, the Armenian V. sylvestris gene pool conserves a high genetic diversity, displaying 292 different alleles with 12.167 allele per loci. The clustering analyses and diversity parameters supported eight genetic groups with 5.6% admixed proportion. The study of genetic polymorphism at the Ren1 locus revealed that 28 wild genotypes carried three R-alleles and 34 wild genotypes carried two R-alleles associated with PM resistance among analyzed 107 wild individuals. This gene pool richness represents an immense reservoir of under-explored genetic diversity and breeding potential. Therefore, continued survey and research efforts are crucial for the conservation, sustainable management, and utilization of Armenian wild grape resources in the face of emerging challenges in viticulture. [ABSTRACT FROM AUTHOR]

In this work, the characteristics of thermal agro-climate resources of the Ararat valley and the foothill zone are studied and calculated and the patterns of their spatial and temporal distribution, as well as interannual variability, are analyzed and evaluated. Previously published works and relevant studies served as the theoretical and informational foundations. The daily data of actual observations of meteorological stations of the Hydrometeorology and Monitoring Center of the SNCO of the Ministry of Environment of the Republic of Armenia in the study area, as well as agro-climate reference books and yearbooks were used as the source material. The following methods were applied in the work: mathematical-statistical, extrapolation, interpolation, analytical, correlation methods, as well as the methods of analysis and analogue. The territory of the Ararat valley and the foothill zone, which has a relatively arid climate, is the most favorable agricultural region of the republic in terms of climate indicators of thermal agro-climate resources. The thermal conditions of the region are favorable for the growth and development of various crops; however, the danger of late spring and early autumn frosts must be taken into account. Measures for adapting agricultural production to climate change are proposed. The results we obtained can be used in planning the development of agricultural production on the territory of the Ararat valley and the foothill zone in the development of agro-climate cadastres of territories and climate services for sectors of the national economy. [ABSTRACT FROM AUTHOR]

The article describes a new detector, a volume filled with hexane at low pressure (3 Torr), containing multi-wire proportional chambers and a silicon semiconductor detector. Using this setup, alpha particles emitted during the decay of the radioactive isotope 226Ra were detected. The device has an energy resolution of ≤ 5% and allows measuring the ionization energy losses of alpha particles as well. Thus, the LPMWPC and SSD-based experimental setup is a good tool for studying both binary and ternary fission of heavy nuclei, in which the third fragment is a high-energy alpha particle. [ABSTRACT FROM AUTHOR]

The reaction of 1-(3,4-dimethoxy)phenylcycloalkanemethane- and 4-(3,4-dimethoxyphenyl)tetrahydropyran-4-methanamines with benzo[d][1,3]dioxol-5-carbonyl chloride was used to synthesize N-substituted benzo[d][1,3]dioxol-5-carboxamides. The cyclization of the latter with phosphorus oxychloride gave dihydroisoquinolines, whose subsequent reduction with sodium borohydride to spiro-substituted tetrahydroisoquinolines followed by Eschweiler–Clark reaction gave N-methyl derivatives. The condensation of the starting amines with benzo[d][1,3]dioxol-5-carbaldehyde formed Schiff bases, which were reduced with sodium borohydride to obtain the corresponding secondary amines―acyclic analogs of tetrahydroisoquinolines. The cyclization of the latter products under Eschweiler–Clark reaction resulted in the synthesis of N-benzodioxolmethyl-substituted tetrahydroisoquinolines. [ABSTRACT FROM AUTHOR]

Electromagnetic fields of relativistic charged particles have a broad frequency spectrum and a sophisticated spatial structure. Field lines offer a visual representation of this spatial structure. In this article, we derive a general set of equations for the field lines of any moving charged particle. The electric field lines are completely determined by the unit vector from the retarding point to the observation point. After proper transformations, the field line equations describe the rotation of this vector with an angular velocity coinciding with Thomas precession. In some cases, including all planar trajectories, the field line equations reduce to linear differential equations with constant coefficients. We present a detailed derivation of these equations and their general analytical solution. We then illustrate this method by constructing field lines for the "figure eight" motion of an electric charge moving under the influence of a plane wave, including complex field lines in three dimensions. [ABSTRACT FROM AUTHOR]

The diabetic kidney disease (DKD) is the major cause of the chronic kidney disease (CKD). Enhanced plasma vasopressin (VP) levels have been associated with the pathophysiology of DKD and CKD. Stimulation of VP release in DKD is caused by glucose-dependent reset of the osmostat leading to secondary pathophysiologic effects mediated by distinct VP receptor types. VP is a stress hormone exhibiting the antidiuretic action in the kidney along with broad adaptive effects in other organs. Excessive activation of the vasopressin type 2 (V2) receptor in the kidney leads to glomerular hyperfiltration and nephron loss, whereas stimulation of vasopressin V1a or V1b receptors in the liver, pancreas, and adrenal glands promotes catabolic metabolism for energy mobilization, enhancing glucose production and aggravating DKD. Increasing availability of selective VP receptor antagonists opens new therapeutic windows separating the renal and extra-renal VP effects for the concrete applications. Improved understanding of these paradigms is mandatory for further drug design and translational implementation. The present concise review focuses on metabolic effects of VP affecting DKD pathophysiology. [ABSTRACT FROM AUTHOR]

In the language of zero multiplicities of subpolynomials, the sufficient conditions are found under which a polynomial of two variables is hyperbolic with a given weight when its leading part is Gårding hyperbolic. [ABSTRACT FROM AUTHOR]

Purpose of Review: Heart failure (HF) is one of the leading causes of cardiac morbidity and mortality around the world. Our evolving understanding of the cellular and molecular pathways of HF has led to the identification and evaluation of a growing number of HF biomarkers. Natriuretic peptides remain the best studied and understood HF biomarkers, with demonstrated clinical utility in the diagnosis and prognostication of HF. Less commonly understood is the utility of HF biomarkers for guiding and monitoring treatment response. In this review, we outline the current HF biomarker landscape and identify novel biomarkers that have potential to influence HF treatment response. Recent Findings: An increasing number of biomarkers have been identified through the study of HF mechanisms. While these biomarkers hold promise, they have not yet been proven to be effective in guiding HF therapy. Summary: A more developed understanding of HF mechanisms has resulted in an increased number of available pharmacologic HF therapies. In the past, biomarkers have been useful for the diagnosis and prognostication of HF. Future evaluation on their use to guide pharmacologic therapy is ongoing, and there is promise that biomarker-guided therapy will allow clinicians to begin personalizing treatment for their HF patients. [ABSTRACT FROM AUTHOR]

Background: Sutureless aortic bioprostheses are increasingly being used to provide shorter cross-clamp time and facilitate minimally invasive aortic valve replacement. As the use of sutureless valves has increased over the past decade, we begin to encounter their degeneration. We describe clinical outcomes and technical aspects in patients with degenerated sutureless Perceval (CorCym, Italy) aortic bioprosthesis treated with valve-in-valve transcatheter aortic valve replacement (VIV-TAVR). Methods: Between March 2011 and March 2023, 1310 patients underwent aortic valve replacement (AVR) with Perceval bioprosthesis implantation. Severe bioprosthesis degeneration treated with VIV-TAVR occurred in 32 patients with a mean of 6.4 ± 1.9 years (range: 2–10 years) after first implantation. Mean EuroSCORE II was 9.5 ± 6.4% (range: 1.9–35.1%). Results: Thirty of thirty-two (94%) VIV-TAVR were performed via transfemoral and two (6%) via transapical approach. Vascular complications occurred in two patients (6%), and mean hospital stay was 4.6 ± 2.4 days. At mean follow-up of 16.7 ± 15.2 months (range: 1–50 months), survival was 100%, and mean transvalvular pressure gradient was 18.7 ± 5.3 mmHg. Conclusion: VIV-TAVR is a useful option for degenerated Perceval and appears safe and effective. This procedure is associated with good clinical results and excellent hemodynamic performance in our largest single-center experience. [ABSTRACT FROM AUTHOR]

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The black rhinoceros (Diceros bicornis L.) is a critically endangered species historically distributed across sub-Saharan Africa. Hunting and habitat disturbance have diminished both its numbers and distribution since the 19th century, but a poaching crisis in the late 20th century drove them to the brink of extinction. Genetic and genomic assessments can greatly increase our knowledge of the species and inform management strategies. However, when a species has been severely reduced, with the extirpation and artificial admixture of several populations, it is extremely challenging to obtain an accurate understanding of historic population structure and evolutionary history from extant samples. Therefore, we generated and analyzed whole genomes from 63 black rhinoceros museum specimens collected between 1775 and 1981. Results showed that the black rhinoceros could be genetically structured into six major historic populations (Central Africa, East Africa, Northwestern Africa, Northeastern Africa, Ruvuma, and Southern Africa) within which were nested four further subpopulations (Maasailand, southwestern, eastern rift, and northern rift), largely mirroring geography, with a punctuated north–south cline. However, we detected varying degrees of admixture among groups and found that several geographical barriers, most prominently the Zambezi River, drove population discontinuities. Genomic diversity was high in the middle of the range and decayed toward the periphery. This comprehensive historic portrait also allowed us to ascertain the ancestry of 20 resequenced genomes from extant populations. Lastly, using insights gained from this unique temporal data set, we suggest management strategies, some of which require urgent implementation, for the conservation of the remaining black rhinoceros diversity. [ABSTRACT FROM AUTHOR]