Search Results (554)

Background/Objectives: Sosnowsky’s hogweed Heracleum sosnowskyi, which originated in the Greater Caucasus region and spread rapidly across Central and Eastern Europe after being introduced as cattle fodder in the 1950s, is an example of an extremely dangerous invasive species listed by the European Union. This study aimed to estimate the genetic diversity of 6 native populations of Sosnowsky’s hogweed from the Caucasus region of Russia and Georgia, as well as 15 invasive populations from Lithuania and Poland, and to assess the adaptability of hogweed in new environments. Methods: Genetic analyses of plant material were conducted, including DNA extraction, ISSR genotyping, PCR product separation, and subsequent molecular data mining and analysis. Results: A pairwise Mantel test revealed a positive correlation between geographical distance and the genetic diversity of the hogweed populations. The presence of three distinct allele pools was confirmed in the populations under study, with genotypes from Poland dominated by the first allele pool, which had the largest number of polymorphic and private loci. Analysis of molecular variance by origin showed that 99% of the variation was within the analysed hogweed populations, with only 1% being between them. Native populations from Russia were genetically distinct from those in Poland and Lithuania. Some of the Georgian population shows genetic similarities to Russians, while the rest shows similarities to the secondary invasive Lithuanians. Conclusions: Introduced populations of H. sosnowskyi are characterised by considerable genetic variation, likely resulting from multiple introductions and subsequent evolutionary processes, which may facilitate local adaptation and invasiveness, although overall large-scale genetic differentiation remains low. Full article

A zinc complex of chelidonic acid (4-oxo-4H-pyran-2,6-dicarboxylic acid) was obtained by reaction with zinc oxide under isothermal conditions. Its composition was confirmed by elemental and thermogravimetric analyses, and its molecular structure was characterized using NMR and IR spectroscopy. Single-crystal X-ray diffraction revealed that the complex crystallizes as a one-dimensional coordination polymer, [ZnChel(H₂O)₄]_n, in the triclinic space group P-1, featuring a distorted octahedral Zn(II) center coordinated by two chelidonate ligands and four water molecules. This six-coordinate arrangement contrasts with previously described tetra-coordinated Zn–chelidonate complexes. Quantum-chemical calculations and molecular dynamics simulations indicated that, in aqueous solution, Zn(II) preferentially forms a monodentate ZnChel(H₂O)₅ species, consistent with the solid-state coordination environment. The interaction of the complex with bovine serum albumin (BSA) was examined by fluorescence, UV–Vis absorption, and circular dichroism spectroscopy, revealing a mixed static–dynamic quenching mechanism, moderate binding affinity, and hydrogen-bonding/van der Waals contributions accompanied by alterations in BSA secondary structure. These results expand the structural chemistry of chelidonic acid and provide biophysical insight into the protein-binding behavior of zinc chelidonate, supporting its potential relevance as a zinc-based bioactive compound. Full article

Geoheritage is commonly regarded as an important natural resource for tourism, but the latter can be a factor of risk to the former. A case study in the Western Caucasus, where the rural area of Mountainous Adygeya hosts many geosites (including those that are globally and nationally ranked), sheds light on a novel dimension of the aforementioned nexus, namely benefits to geoheritage from expansion of tourism infrastructure. The latter has grown remarkably in the study area during the past fifteen years. A comparison of 25 geosites as they were in 2010 and 2025 indicates their changes, which can be treated as positive and negative effects of the expansion of tourism infrastructure. Particularly, it is established that this expansion was responsible for the creation of one geosite, the extension of three previously existing geosites, the specialists’ awareness of an additional object, as well as for the improved accessibility of 12 geosites. Several negative effects are also documented, but they are neither major nor widespread due to the superb local environmental management. This example demonstrates that the rapid expansion of tourism infrastructure in rural, geoheritage-rich areas can contribute to their sustainability and not only challenges it. Full article

Polynomial commitment schemes (PCS) enable a prover to commit to a polynomial and later reveal evaluations with succinct, verifiable proofs. As critical components of modern cryptographic systems like Verkle trees and zk-SNARKs, these methods are experiencing a significant transition from classical to post-quantum designs. This comprehensive research systematically compares the major scheme families to examine this progression, from pairing-based KZG and transparent Bulletproofs to lattice-based and hash-based post-quantum alternatives. We present a unified taxonomy that maps the classical-to-post-quantum transition across trust models, security assumptions, and efficiency measures after conducting a PRISMA-guided systematic review of 77 works. Our analysis reveals a fundamental trade-off between efficiency and security: classical schemes, which rely on quantum-vulnerable assumptions, provide optimal performance with constant-sized proofs, while post-quantum alternatives offer quantum resistance at the cost of larger proofs and higher computational overhead. By combining research works, we highlight recurrent problems with adaptive security, verification efficiency, and proof conciseness. We offer a specific research roadmap with prioritized short-, medium-, and long-term directions to close the performance gap between quantum-resistant and classical architectures based on our quantitative analysis. This study offers a technical reference and a strategic roadmap for constructing practical post-quantum polynomial commitments. Full article

The energy-intensive nature of primary aluminum production necessitates advanced computational tools for process optimization. This study presents a coupled electro-thermal model of an aluminum reduction cell, developed within the framework of smart manufacturing. Using the finite difference method (FDM) implemented in MATLAB R2025b, the model resolves the three-dimensional configuration of a cell with eight prebaked anodes across four distinct physical domains (electrolyte, anodes, cathode, and gas phase). The computational grid comprises approximately 45,000 nodes with refined vertical resolution (Δz = 0.025 m) in the interelectrode gap. The electrostatic solution converges within 150–200 iterations using successive over-relaxation (SOR, ω = 1.5), with a total runtime under 15 min for 30,000 s of simulated physical time on a standard desktop workstation. Simulation results reveal characteristic temperature profiles with maxima reaching 1150 °C and a thermal uniformity index of approximately 130 °C across the central cross-section. The predicted specific energy consumption of 14.0 MWh/t Al aligns with industrial benchmarks. This computationally accessible virtual testbed enables rapid assessment of design modifications and process parameters, supporting the goals of energy efficiency and enhanced operational stability in primary aluminum production. Full article

Federated learning has become a promising paradigm in the training of decentralized machine learning models across clients without sharing raw data, thereby preserving privacy. Current federated support vector machine methods are mainly based on the learning of a single global model, which inadequately addresses the challenges presented by heterogeneous and non-IID client data distributions. To overcome these limitations, we propose FMT-SVM, a novel federated multi-task learning framework that jointly trains both binary and multi-class classification tasks within each client, where the client uses a unified convolutional neural network encoder to extract common features among tasks, which are passed to task-specific linear SVM heads dedicated to each classification task. By leveraging a primal optimization integrating task covariance and global consensus regularization, FMT-SVM explicitly models relationships between heterogeneous tasks and enforces alignment across clients, effectively handling the non-IID nature of data distributions. Unlike traditional FL methods that exchange entire model parameters or large support vector sets, our method communicates only the compact SVM heads during aggregation, greatly reducing communication overhead and enhancing scalability for clients with limited bandwidth. To further enhance privacy, Gaussian differential privacy mechanisms are applied to client updates, balancing privacy preservation with predictive performance. Experiments are performed on two medical image datasets: the Pediatric Pneumonia Dataset and the Breast Ultrasound dataset, demonstrating that the FMT-SVM framework achieves competitive accuracy on both binary and multi-class tasks while maintaining communication efficiency and privacy guarantees. These results highlight the capability of the proposed FMT-SVM framework as a practical, scalable, and privacy-aware solution for the federated true multi-task learning problem in sensitive healthcare applications. Full article

DOM-based Cross-Site Scripting (DOM XSS) remains a critical web application vulnerability due to its exclusive manifestation within client-side execution contexts, rendering traditional server-side defenses ineffective. Existing machine learning approaches achieve high recall but suffer from critically low precision in DOM-specific scenarios. Payload-centric classifiers frequently misclassify syntactically suspicious but semantically benign injections, causing high false positive rates. This paper introduces a context-aware hybrid detection framework integrating dynamic taint tracking with runtime DOM semantic analysis and lightweight machine learning classification. The proposed architecture extracts a 42-dimensional feature vector combining 22 lexical payload features with 20 contextual execution features capturing sink semantics, element type, attribute execution capability, and DOM state properties. A Random Forest classifier is employed to enable low-latency inference and demonstrates potential for real-time deployment. By modeling exploitability as a function of execution context rather than payload syntax alone, the framework significantly reduces false positives while maintaining high detection capability. Experimental evaluation demonstrates that contextual feature integration substantially improves precision compared to payload-only baselines, achieving a favorable precision-efficiency trade-off. The primary contribution lies in elevating runtime semantic context to a first-class feature space for DOM XSS detection, representing a shift from text-centric classification toward execution-aware security modeling in client-side web environments. Full article

The Moroccan locust (Dociostaurus maroccanus) is one of the most economically significant locust species in the Caucasus and Central Asia. In the past, the Mediterranean region also experienced severe damage to crops and pastures, until widespread grassland conversion to cropland began in the second half of the 20th century. However, climate change, environmental shifts, land-use changes, cropland abandonment, and overgrazing are likely to alter the spatial distribution and outbreak patterns of this pest. Understanding potential changes and geographic shifts is essential for proactive pest management, including effective monitoring and control strategies. In this study, we apply Ecological Niche Modelling (ENM) using 12 machine learning algorithms, historical survey data covering the species’ full distribution range, and relevant abiotic variables to identify the most suitable areas for potential mass breeding during 1991–2020 and the near future (2021–2040), based on the “middle-of-the-road” Shared Socioeconomic Pathway (SSP2-4.5) scenario. Our results indicate significant regional shifts. Notably, breeding suitability is projected to increase in parts of Greece, Turkey, Armenia, Georgia, Kyrgyzstan, and Tajikistan. In contrast, countries such as Turkmenistan, Afghanistan, Pakistan, and Spain are likely to experience a decline in optimal breeding areas. The forecast results support field observations of a geographical shift northward and toward higher altitudes. Additionally, higher temperatures in suitable areas suggest more drought-like conditions, which typically promote locust population explosions and outbreaks. If left unaddressed, such outbreaks can cause severe economic damage to affected regions. Full article

Waterfalls are common natural heritage objects. Their assessments often focus on physical properties of waterfalls and/or visitors’ judgments. However, local conditions determining the visibility of waterfalls also matter. These conditions can be understood as visual accessibility. It is proposed to assess the latter semi-quantitatively regarding physical availability of different views of waterfalls, the scalability of these views, opportunities for taking natural photographs and recreation, seasonality, the presence of physical barriers for observation, the influence of natural shadows, and the presence of safety challenges. The assessment procedure is objective because it deals with real landscape peculiarities and not with perceived aesthetics. Several small waterfalls visited by crowds of tourists in two different regions of Russia were used to exemplify the proposed approach. It was established that the Risyoksky and Batareysky waterfalls in the Murmansk Region (Russian Arctic) have limited visual accessibility, and that of the Sakhraysky, Oselkovy, and Filimonova waterfalls in the Republic of Adygeya (Russian South) is moderate. Generally, visual accessibility complicates the perception of waterfalls, and the outcomes of its assessment hold practical importance in natural heritage and tourism management. Full article

The radial growth of the tree stem reflects tree responses to climate change. This study examines the response of Fagus orientalis to more than half a century of climate dynamics in Armenia using a dendrochronological approach. Two forest stands were analyzed: one geographically isolated stand in the arid southern part of the country and one stand in the mesic northern mountainous region, where the main beech forests are distributed. The study period was divided into two phases (1965–1993 and 1994–2023). Climate dynamics were assessed by the months of the biological year, from October of the previous year to the end of September of the current growing season. Substantial warming trends were detected at both stands, except in November, December, and April, and in July in the northern part of Armenia. Between periods, the mean ring width increased from 1.67 mm to 2.14 mm at the northern stand, while decreasing from 1.95 mm to 0.89 mm at the southern stand. Despite climate warming and declining precipitation, some study trees exhibited increased (northern) or stable (both stands) radial growth. Comparison of the two periods revealed pronounced ecological and tree-specific variability in climate–growth relationships, including shifts in correlation strength and sign reversals. These patterns were primarily driven by climate sensitivity rather than age-related effects. The results provide valuable insights for conserving the southern stand and may support assisted migration strategies for F. orientalis toward the southern margin of the F. sylvatica distribution range. Full article

Scots pine (Pinus sylvestris L.) spans most of Eurasia, yet southern and mountainous populations may retain distinctive genetic components shaped by long-term isolation and complex postglacial dynamics. We genotyped 186 trees from four Scots pine stands in Armenia (AM1-AM4) and reference stands from Germany, Russia and Montenegro with the PiSy50k SNP array and integrated these data with published European array datasets from Finland, Poland and the Baltic region. After quality checks and conservative SNP filtering, 627 individuals from 47 populations and 3659 SNP loci were retained. Within-population diversity was generally high; Armenian stands AM2–AM4 were among the most diverse, whereas AM1 showed reduced diversity and the highest differentiation relative to the remainder of the dataset (FST vs. rest = 0.0047). Direct pairwise F_ST and hierarchical AMOVA confirmed pronounced heterogeneity among Armenian stands, with AM1 the most differentiated stand, AM2 and AM4 closest to the broader Eurasian background, and AM3 intermediate. Principal component analysis (PC1 = 1.42%, PC2 = 0.76%) again separated AM1 strongly from all non-Armenian samples, while AM2 overlapped with the central/eastern European cluster and AM3 and AM4 combined continental-like and AM1-like individuals. Structure-like inference with LEA/sNMF showed a broad cross-entropy plateau from approximately K = 4 to K = 6; we therefore use K = 5 as a practical summary, which highlighted a dominant AM1-associated ancestry component and variable continental admixture in AM2–AM4. KING kinship estimates provided little evidence for within-stand family clustering in Armenian stands; no second-degree-or-closer pairs were observed in AM1–AM4. Together, the results reveal pronounced heterogeneity among Armenian Scots pine stands and identify AM1 as a highly differentiated but unresolved genomic component, providing a genomic baseline to support conservation planning, provenance evaluation and the management of forest reproductive material in the Lesser Caucasus. Full article

Two Zn(II) coordination compounds based on glaucine-derived Schiff bases were synthesized and investigated as potential materials for dye-sensitized solar cells (DSSCs). The structures of all compounds were established by X-ray diffraction analysis and quantum chemical modeling (DFT/TD-DFT). Their photophysical properties (absorption and luminescence spectra in solution and the solid state), electrochemical characteristics, and photovoltaic parameters in DSSC devices were studied. The highest power conversion efficiency (PCE ~5.18%) was demonstrated by the free ligands, which is attributed to their favorable absorption spectrum and optimal alignment of energy levels relative to the conduction band of TiO₂ and the redox couple of the electrolyte. The Zn(II) coordination compounds exhibited significantly lower efficiency (~2.1%). Impedance spectroscopy results indicated more efficient charge transfer at the TiO₂/dye/electrolyte interface for the organic derivatives. Full article

Located in northeastern Anatolia, Çıldır and Ardahan serve as a gateway to the Caucasus for political entities such as the state and mobile groups such as the tribe. Due to this geopolitical characteristic, the region has fallen under the dominion of numerous states and civilizations throughout history. With its fertile highlands, Lake Çıldır, and natural water resources like the Kura River, the area constitutes an attractive living space for hem settled agriculturalists and nomadic tribe groups subsisting on animal husbandry. These features have profoundly influenced the ethnic, demographic, socio-economic, and cultural fabric of the region. Following the establishment of Ottoman sovereignty in the 16th century, Çıldır and Ardahan assumed a vital role in the state’s Caucasian and Eastern policies. This research addresses the Turkmen tribe and other ethnic communities residing around the eyalet of Çıldır and the sanjak of Ardahan. It further examines the banditry activities carried out by these groups, the attitudes of central and local administrators toward such activities, migration and settlement patterns, and the economic and political pressures exerted by the Russian State upon these tribes. The political and economic pressures exerted by the Russian State on these tribes reflect a broader imperial strategy of frontier making, as discussed by Khodarkovsky in the context of Russia’s expansion into its southern borderlands. By positioning the region as a negotiated frontier, this study moves beyond a descriptive narrative to analyze how tribal mobility and settlement functioned as tools of sovereignty and resistance within the broader context of Ottoman state formation and trans-imperial rivalry. The methodology employed in this study is the Qualitative Research Method; accordingly, documents from the Presidential Ottoman Archives (BOA) were transcribed, and the relevant sections were interpreted and incorporated into the study. The archival findings are contextualized within recent historiographical debates concerning the shifting definition of the state versus nomadic agency during the transition from the 18th to the 19th century. While existing literature contains academic studies aiming to elucidate the archaeological, geographical, economic, and administrative structures of Çıldır and Ardahan, it has been determined that no academic research has been conducted to analyze the ethno-socio-demographic structure of the region specifically focusing on the 18th and 19th centuries in a historical sense. With this focus on the interplay between imperial frontiers and tribal identity, this study provides a critical analysis of how local dynamics shaped the grand strategies of the Ottoman and Russian Empires. Full article

A comprehensive understanding of Callovian (Middle Jurassic, Mesozoic) sedimentation and paleogeography requires examination of marine deposits of this stage across multiple geological domains on Earth. The Western Caucasus is a key region for Callovian studies in the central Northern Neotethys, but the age of its Callovian marine deposits remains uncertain. A reference section was examined, and a horizon containing foraminifers was found in the Kamennomostskaya Formation. The assemblage comprises both agglutinated and calcareous forms and is dominated by Labalina costata (Antonova, 1958). Data from other regions permit hypothesizing an Early Callovian age for the horizon based on the foraminifers. Considering recent findings of macro- and microfossils, the age of the entire Kamennomostskaya Formation can be constrained to the Early Callovian—older than previously thought. It is proposed that the Middle Callovian corresponds locally to a hiatus. This age revision facilitates a comparison between regional and global sea-level changes. Apparently, there was eustatic control over Early Callovian marine sedimentation in the Western Caucasus. Full article

2-Aryl-2-(3-indolyl)acetohydroxamic acids have emerged as promising antitumor agents; however, their poor pharmacokinetic profile remains a significant drawback. To address this limitation, we have synthesized a homolog of such acids—specifically 2-aryl-2-(3-indolyl)propionic acid (IC₅₀ > 100 mM (U87)), along with several other derivatives: ethyl ester (IC₅₀ > 100 mM (U87)), hydroxamate (IC₅₀ 21.2 ± 1.0 mM (U87)) and hydrazide (IC₅₀ > 100 mM (U87)). The cytotoxicity of these compounds against glioblastoma cell lines was evaluated and compared to that of the parent acetohydroxamic acid derivatives. Full article