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Historické vodné nádrže - klauzy v Nízkych Tatrách (Slovensko)
(Výzkumný ústav vodohospodářský T. G. Masaryka : Praha, 2026) Cimbala, Jakub; Hronček, Pavel; Hrončeková Gregorová, Bohuslava
Príspevok analyzuje vývoj historických vodných nádrží (klauz) v oblasti Nízkych Tatier na základe interpretácie mapových diel od polovice 19. storočia po súčasnosť. Klauzy v minulosti slúžili ako súčasť systému na splavovanie dreva do povodí riek Hron a Váh. Predstavovali kľúčový vodotechnický prvok, ktorý významne ovplyvnil vodný režim tokov a formovanie horskej krajiny. Identifikácia historických klauz bola založená na analýze máp II. vojenského mapovania (1836–1852), ktoré boli porovnané so súčasnými mapovými podkladmi (Základná báza údajov pre geografický informačný systém – ZBGIS, Ortofotomapa SR) a overené terénnym výskumom. Na historických mapách bolo identifikovaných 14 klauz. Ich celková historická rozloha predstavovala 6,28 ha (II. vojenské mapovanie), z ktorých sa len malá časť zachovala dodnes s rozlohou 2,19 ha (ZBGIS – súčasné mapovanie). Výsledky poukazujú na výrazný úbytok historických vodných plôch, pričom časť klauz zanikla v dôsledku poškodenia hrádze, sedimentácie, sukcesie, alebo zmien využívania územia, zatiaľ čo iné sa zachovali len vo forme reliktov hrádzí, príp. boli transformované na nové retenčné nádrže. Príspevok zdôrazňuje význam historických klauz nielen z hľadiska historicko-geografického výskumu, ale aj v kontexte súčasných adaptačných opatrení na zmenu klímy v horskej krajine.
Rational divergence measures on intuitionistic fuzzy sets
(Balgarska akademiya na naukite : Sofia, 2026) Kobza, Vladimír
This paper investigates the theoretical foundations and practical applications of rational divergence measures within the framework of fuzzy set theory. Unlike traditional distance metrics, rational divergence measures are characterized by their functional form, typically expressed as a ratio of membership functions or set cardinalities, which allows for a more nuanced quantification of the "informational gap" between fuzzy sets. The study explores the axiomatic properties of these measures, focusing on their ability to handle non-linearity and uncertainty in complex data structures. By examining rational forms of divergence, such as those derived from the Jaccard-like ratios or specialized f-divergences, this work demonstrates how these measures overcome the limitations of standard Euclidean distances in high-dimensional fuzzy spaces. Key emphasis is placed on their role in multi-criteria decision-making (MCDM) and pattern recognition, where the rational expression of divergence provides a more stable and intuitive measure of dissimilarity. Furthermore, the paper provides a comparative analysis of different rational divergence formulations, evaluating their sensitivity to membership fluctuations and their performance in clustering algorithms. The results suggest that rational divergence measures offer superior discriminative power, making them a tool for modeling expert knowledge and imprecise information in modern intelligent systems. Many authors investigated the possibilities how two fuzzy sets can be compared. The basic study of fuzzy sets theory was introduced by Lotfi Zadeh in 1965. We discuss the divergences defined on more general objects, namely intuitionistic fuzzy sets (IFSs). We have focused on special class of divergences, since some restriction conditions are necessary. This approach to the divergence measure is motivated by class of the rational similarity measures between fuzzy subsets expressed using some set operations (namely intersection, complement, difference, and symmetric difference) and their scalar cardinalities. In this study, we have considered the value of divergence between IFSs as a Σ-count of two scalar cardinalities, i.e. as a pair of real numbers.
Deer keds (Diptera: Hippoboscidae) as potential vectors of bacterial and protozoan pathogens in Slovakia
(Elsevier B. V. : Amsterdam, 2026) Švirlochová, Klaudia Mária; Víchová, Bronislava; Syrota, Yaroslav; Oboňa, Jozef; Heglasová, Ivana; Vargová, Lucia; Stanko, Michal; Csanády, Alexander; Čisovská Bazsalovicsová, Eva; Zubriková, Dana
Deer keds are ectoparasitic flies of wild ruminants and are increasingly recognised as potential vectors of various pathogens. This study aimed to assess the prevalence of selected vector-borne pathogens in wingless deer keds collected from 13 red deer and 2 fallow deer, as well as in host-seeking keds across multiple localities in Slovakia. In total, 240 flies identified as Lipoptena spp. were obtained from cervids, and 542 host-seeking deer keds were collected. Individual flies were screened using molecular methods for the presence of Borrelia spp., Bartonella spp., Rickettsia spp., haemotropic Mycoplasma spp., Anaplasma phagocytophilum, piroplasmids, and Kinetoplastida. In wingless Lipoptena spp., high DNA prevalence rates were detected for Bartonella spp. (88.33%), piroplasmids (60.83%), Anaplasma phagocytophilum (24.58%), and Kinetoplastida (20.42%). Haemotropic Mycoplasma spp. DNA was confirmed in 4.56% of flies, while DNA of Borrelia spp. and Rickettsia spp. was not detected. Among host-seeking keds, Bartonella spp. DNA was detected in 7.38%, Rickettsia spp. DNA in 0.92%, and haemotropic Mycoplasma spp. DNA in 0.37%, whereas the remaining pathogens were not detected. Regression analysis indicated significantly greater pathogen-group richness in deer keds collected from cervids, as host-seeking keds harboured an average of 1.76 fewer pathogen types than host-derived individuals. The probability of detecting Bartonella spp. and haemotropic Mycoplasma spp. was markedly lower in host-seeking keds. Overall, this study highlights the epidemiological relevance of Lipoptena spp. and underscores the need for further research on their vector competence and potential implications for animal and public health.
Artificial neural network-based optimization of CO₂ laser cutting parameters for beech plywood and HDF: A kerf geometry perspective
(University of Zagreb, 2026) Ružiak, Ivan; Der, Oguzhan; Kubovský, Ivan; Adijans, Imants; Kučerka, Martin; Richvalská, Jana; Gajtanska, Milada; Tudor, Eugenia Marianna; Todaro, Luigi; Štefančin, Lukáš
This study presents the results of Artificial Neural Networks (ANN) predictions with the aim of optimizing the process of beech plywood and HDF laser cutting. A survey is given of the results of predictions of cutting kerf parameters made by Artificial Neural Networks to cover a wide spread of CO2 laser parameters, as well as the results of experimental cutting with maximum laser power (P) equal to 135 W and maximum feed rate (v) equal to 20 mm/s. Validity of the best neural network was checked versus overfitting of the best neural networks, confirmed according to r value of the model (minimum 0.971), MAPE (%) (maximum 6.21 %) and compared with the results of other authors. The article also presents the effect of energy density values E on values of cutting kerf parameters and their variance. The results show that the optimal value of laser power (P) and feed rate (v) for beech plywood are (200-300 W; 10-15 mm/s), while for more dense and more homogenous high-density fibreboard (HDF) they are (300-500 W; 5-10 mm/s). Optimal energy densities (E) are then 133 MJ/m2 for beech plywood and 433 MJ/m2 for HDF. Similar as for other wooden materials, it follows that more dense species of wood should be cut with higher values of energy densities. The results can be applied to reduce the material and energy demands by optimizing the quality of cut with minimum symmetrical kerf widths.
People and bears: Evaluating public attitudes to foster human-carnivore coexistence in Slovakia
(Associazione Teriologica Italiana : Rím, 2025) Franchini, Marcello; Švajda, Juraj; Uhrín, Marcel; Prokop, Pavol
The brown bear (herein, bear) Ursus arctos has been exhibiting an increasing population trend in Slovakia. This rise in population has led to human–bear conflicts (HBCs), mainly in the form of livestock predation and agricultural damage. In this study, we provide one of the first assessments of public attitudes toward the presence of bears in Slovakia to suggest management and conservation strategies. From January to March 2022, we randomly distributed 1,000 anonymous electronic questionnaires among people living in areas with either bear presence or absence within Slovakia. Data were subsequently analyzed using Cumulative Link Models. Women, despite showing greater fear of bears than men, were more sensitive to the need for mitigating HBCs. Older and less–educated respondents predominantly exhibited a negative attitude toward the presence of bears compared to younger and more–educated individuals. Respondents living in areas with bear occurrence exhibited lower trust in organizations responsible for bear management, demonstrated more negative attitudes toward bear presence, and were more in favor of lethal control or translocation of problematic individuals. Educational activities that explain the important role carnivores play in maintaining ecosystem functionality, as well as their economic benefits through tourism, should be emphasized to enhance bear acceptance, particularly among individuals residing in areas with permanent bear populations. Furthermore, the engagement of scientists on social media is crucial to prevent negative portrayals of bears, which could influence human attitudes toward their presence. Conservation campaigns should provide guidance on recommended human behaviors (e.g., proper waste disposal) to minimize the attraction of bears to urban areas and strategies for reducing the risk of human–bear encounters in natural settings.
Semantic causality evaluation of correlation analysis utilizing large language models
(Tech Science Press : Henderson, 2026) Dudáš, Adam
It is known that correlation does not imply causality. Some relationships identified in the analysis of data are coincidental or unknown, and some are produced by real-world causality of the situation, which is problematic, since there is a need to differentiate between these two scenarios. Until recently, the proper−semantic−causality of the relationship could have been determined only by human experts from the area of expertise of the studied data. This has changed with the advance of large language models, which are often utilized as surrogates for such human experts, making the process automated and readily available to all data analysts. This motivates the main objective of this work, which is to introduce the design and implementation of a large language model-based semantic causality evaluator based on correlation analysis, together with its visual analysis model called Causal heatmap. After the implementation itself, the model is evaluated from the point of view of the quality of the visual model, from the point of view of the quality of causal evaluation based on large language models, and from the point of view of comparative analysis, while the results reached in the study highlight the usability of large language models in the task and the potential of the proposed approach in the analysis of unknown datasets. The results of the experimental evaluation demonstrate the usefulness of the Causal heatmap method, supported by the evident highlighting of interesting relationships, while suppressing irrelevant ones.
Universal minimal flows from a homotopical perspective
(Springer-Verlag : Heidelberg, 2026) Dirbák, Matúš
We study universal minimal flows of connected and locally contractible topological groups by means of tools from homotopy theory and dynamical cohomology. We provide methods for computing their first cohomotopy groups and illustrate them by computations related to connected Lie groups and identity components of homeomorphism groups of compact connected surfaces with or without boundary. Since metrizable spaces have countable first cohomotopy groups, these methods serve as a useful new instrument for proving nonmetrizability of various universal minimal flows. In this way we reprove several results in this direction known before and also prove some new ones. Finally, we indicate how our methods can be used to construct finite-dimensional minimal spaces for infinite-dimensional topological groups, having all orbits of first category.
Students' intrinsic motivation in the context of inquiry-based geography instruction
(Wydawnictwo Adam Marszałek : Toruń, 2025) Škodová, Martina
The main aim of the study was to determine whether the implementation of inquiry-based geography instruction had a positive effect on intrinsic motivation of lower secondary school students. A quasi-experimental design was employed, in which students attended both traditional and inquiry-based lessons. The research instrument was the standardised Intrinsic Motivation Inventory (IMI). The collected data were processed using the software R. The results revealed that inquiry-based instruction had a significantly positive effect on students’ intrinsic motivation. This finding serves as an important argument for implementing inquiry-based elements in education – an approach emphasised in the new national curriculum in Slovakia.
Smart sustainable cities as digital ecosystems: Concept and framework description
(Hapres : Londýn, 2025) Kozhevnikov, Sergei; Svítek, Miroslav
Cities are increasingly understood as complex adaptive systems composed of interdependent social, economic, environmental, and technological subsystems. Traditional smart city models—focused on isolated technologies—fail to address this complexity. This study introduces a conceptual and technical framework that redefines the smart city as a digital ecosystem, where autonomous agents represent urban actors—including citizens, infrastructures, services, and industrial entities. These agents operate within shared data spaces, common ontologies, and negotiation protocols, enabling distributed decision-making, adaptive coordination, and continuous cross-domain co-evolution. The framework was examined through three practical cases: (1) a multi-agent traffic management system in Taipei that improves flow efficiency and reduces emissions; (2) an adaptive multi-resource smart-grid model demonstrating self-organizing balancing of electricity, gas, and heat; and (3) a cross-domain integration scenario linking Smart City (SC) and Industry 4.0 ecosystems through semantic mediation and multi-agent negotiation. Results show that ecosystem-based urban management enables real-time optimization, interoperability, sustainability and resilience across sectors. The paper further introduces the Digital Ecosystem Sustainability Evaluation System (DESES)—a method for assessing sustainability as an emergent, adaptive property rather than a static collection of KPIs. The study shows that digital ecosystems shift sustainability and resilience from predefined policy targets to emergent outcomes of system design. This paradigm enables cities to self-organize, co-evolve with their environment, and respond adaptively to disruptions. The proposed framework offers a foundation for next-generation urban management systems that integrate people, technologies and governance within a unified, living digital ecosystem.
Correlation n-star Graphs
(IPSI : Belehrad, 2026) Dudáš, Adam; Modrovičová, Bianka
When working with correlation analysis and the visualization of its results and processes, the systematic identification of correlation classes is often overlooked. Such classes can be described as sets of attributes of the studied dataset that share similar correlation patterns − like the strength and direction of the relationship measured between a pair of attributes − and can be used as a method of identification of significant and insignificant correlations while introducing an attribute hierarchy for automated predictive analysis. This work proposes correlation n-star graphs, a graph-based visualization model designed to support automatic identification of these classes in multidimensional datasets. The work focuses on the design of the visualization model, a Python implementation of the proposed concept, and an experimental evaluation on three benchmark datasets assessing both qualitative and quantitative aspects of the visualization and correlation classification.
Evaluation of the attractiveness of historical water reservoir relicts (splash dams) in the forest environment of the Low Tatras National Park (Slovakia) in terms of ecotourism
(Multidisciplinary Digital Publishing Institute : Basel, 2026) Cimbala, Jakub; Hrončeková Gregorová, Bohuslava; Hronček, Pavel; Tometzová, Dana
This study focuses on the identification, historical-geographical description, and subsequent evaluation of the attractiveness of relicts of historical water reservoirs (splash dams) in the forest environment of the Low Tatras National Park (Slovakia), situated in the central part of the Western Carpathians, with regard to their potential for ecotourism development. Recreational and leisure activities in this area are primarily based on soft tourism forms. In the national park, we identified fourteen relicts of splash dams, and for the assessment of their attractiveness in terms of ecotourism, we selected the five largest. All splash dams were assessed using a methodology developed by the authors as an outcome of their research, in order to fulfil one of the partial objectives of the study. The methodology comprises 19 evaluation criteria grouped into three categories: natural environment, technical characteristics, and recreational potential. Based on the application of this authordeveloped methodology, it was determined that the Malužiná splash dam represents the most attractive site for ecotourism, as it remains water-filled and is readily accessible via two cycling routes. In terms of the evaluation according to technical criteria, the most attractive relic is the Korytnica splash dam, which ranks as the second most attractive among the assessed splash dams in the national park.
Mountain grasslands as carbon sinks and energy hubs: a study of Western Carpathians in Slovakia
(Nature Publishing Group : London, 2026) Kizeková, Miriam; Britaňák, Norbert; Čunderlík, Jozef; Hanzes, Ľubomír; Pollák, Štefan; Vargová, Vladimíra; Jančová, Ľubica; Kanianska, Radoslava
Mountain grasslands are unique ecosystems that provide many ecosystems’ services. They are an important carbon pool and can also act as a source of bioenergy. The study focused on 4 grassland types (Lowland hay meadows, Mountain hay meadows, Wet grassland of sub-montane zones and Artificial grasslands) and 4 soil types (Fluvisols, Cambisols, Leptosols, Stagnosols) in 5 mountain ranges (Great Fatra Mts., Low Tatra Mts., Slovak Paradise Mts., Čergov Mts., Slánske Hills Mts.) of the Western Carpathians in Slovakia. The results showed that of the total carbon stock of the mountain ecosystems equal to 2.120 × 103 tons, 94% was stored in soil. The total carbon density followed this pattern: Fluvisols (100.64 ± 7.87 t/ha) > Stagnosols (84.17 ± 7.90 t/ha) > Leptosols (56.34 ± 6.20 t/ha) > Cambisols (55.43 ± 5.09 t/ha). Soil organic carbon density was also significantly affected by elevation, with the highest values between 600 and 900 m asl. (70.46 ± 4.23 t/ha). Grassland type significantly affected carbon density in living plant biomass, where Mountain hay meadows showed the significantly lowest values (P < 0.05) for carbon density in above-ground biomass (0.79 ± 0.05 t/ha) and below-ground biomass (2.24 ± 0.16 t/ha). The hierarchical clustering dendrogram revealed that the soils from the Low Tatra Mts. differed significantly from those of other mountain ranges and were characterized by high pH, very high soil organic carbon content, high levels of plant-available magnesium, and high C: N ratio in the soil. The calculated biomethane production ranged from 6,606 GJ in the Slovak Paradise Mts. for Lowland hay meadows, to 122,888 GJ in the Low Tatra Mts., which had the largest area of grassland habitats. The total theoretical energetic potential of biomethane production from all evaluated grassland habitats exceeded 1,139 GJ. The energetic potential values followed the following order: Slovak Paradise Mts. < Čergov Mts. < Slánske Hills Mts. < Great Fatra Mts. < Low Tatra Mts.
Phenological effects of artificial light at night on urban trees: A case study on microclimate and light pollution
(Elsevier GmbH : Jena, 2026) Škvareninová, Jana; Kaniansky, Stanislav; Škvarenina, Jaroslav; Korená-Hillayová, Michaela; Kanianska, Radoslava
Artificial light at night (ALAN) is a pervasive but understudied stressor for urban trees, significantly affecting their phenology. The study investigates the impact of ALAN on autumn leaf colouring (LC10 % and LC100 %) in Acer pseudoplatanus, Acer platanoides, and Betula pendula in urban settings during 2016 and 2023. Using Linear Mixed Models, we analyzed phenological timing in illuminated (L) versus non-illuminated (N) crown parts, considering meteorological factors. Our results show that ALAN significantly delays the initial leaf colouring (LC10 %), suggesting an extension of the growing season. However, this effect did not significantly vary across species or crown parts, indicating a broad initial sensitivity. For complete leaf colouring (LC100 %), ALAN's direct influence diminished, with meteorological conditions emerging as primary drivers. Both species-specific traits and microclimatic differences within the crown consistently proved highly significant for both phenophases, highlighting inherent variability. Crucially, although ALAN's overall effect on species-specific senescence timing was not statistically distinct, species that naturally senesce later (e.g., Betula pendula) experienced disproportionately greater ALAN-induced delays in LC100 %. This strong positive correlation between natural senescence onset and ALAN-induced delay for complete leaf colouring underscores a critical vulnerability for late-season species. These findings emphasise the complex interplay between ALAN, meteorological factors, and species-specific responses in urban tree phenology. Understanding these dynamics is vital for sustainable urban trees management, guiding species selection and lighting design to mitigate negative impacts on tree health and urban ecosystem services.
Do we collect adequate and relevant biodiversity data? A case study of the Malá Fatra National Park (Slovakia)
(Verlag der Österreichischen Akademie der Wissenschaften : Innsbruck, 2026) Repáňová, Dana; Švajda, Juraj
Monitoring biodiversity is crucial for comprehending the status and distribution of species, thereby aiding in the management and conservation of protected areas. Malá Fatra National Park, renowned in Slovakia for its natural richness and envi-ronmental diversity, has undergone biodiversity monitoring for decades, with data consolidated in the Comprehensive Information and Monitoring System. This study assesses mapping efforts across various taxonomic groups within the park and highlights characteristics of adequately mapped groups. It presents heat maps depicting biodiversity hotspots generated through QGIS, analysing 48,995 observations and 1,558 mapped plant and animal species by the end of 2022. Findings indicate that plants represent the most mapped organism group, while animals record the highest number of observations. Mapping levels vary significantly across taxonomic groups, with Tracheophyta, Aves and Mammalia relatively well-mapped, contrasting with poorly mapped groups such as Bryophyta and Invertebrata. Geographically, Rozsutec and Suchý Nature Reserves are the best-mapped areas, with Rozsutec identified as a significant hotspot. These results underscore the necessity for intensified mapping efforts to enhance understanding of the area’s biodiversity and species distribution.
A Trojan horse inside the gates: Alien-native mating interactions in mixed populations in Solidago taxa
(John Wiley & Sons : Weinheim, 2026) Skokanová, Katarína; Murgašová, Michaela; Pulišová, Kristína; Šingliarová, Barbora
The establishment and possible impacts of alien–native hybrids depend on their formation frequency and ability to spread using generative and vegetative reproduction. Here, we investigated the frequency and pathways of hybrid Solidago ×niederederi formation and its subsequent mating interactions with parental species in mixed populations of invasive alien S. canadensis and native S. virgaurea. DAPI flow cytometry was used for progeny screening (991 seedlings) of the 15 plants from two mixed populations to document their mating interactions based on previously shown differences in relative genome size of the studied taxa. Seedlings of presumed hybrid origin (F1 hybrids) were formed at low frequency (up to 3%) by both S. canadensis and S. virgaurea. About 46% of germinating seeds produced by S. ×niederederi plants represented later hybrid generations. Backcrossing of S. ×niederederi with parental species within the mixed populations was thus intense, but its frequency differed in direction: backcrossing was less frequent with S. virgaurea as pollen donor (<8%), while there was a strong asymmetric pattern towards S. ×niederederi backcrossing with S. canadensis as the pollen donor (almost 47%). Furthermore, the formation of tri- and tetrapolyploid seedlings within the progeny of the two hybrid plants was recorded. Hybridisation and introgression appear to be established in mixed populations of S. canadensis, S. virgaurea and S. ×niederederi. These post-invasion processes might later be mirrored in the spreading success of descendants of the invasive species and genetic erosion of the native species. Therefore, their pathways, extent and consequences require further attention.
Understanding early stages of speciation: Allopatric divergence, introgression and chromosomal dynamics in the Erysimum odoratum species complex
(Academic Press : San Diego, 2026) Bačák, Richard; Šlenker, Marek; Šingliarová, Barbora; Mandáková, Terezie; Skokanová, Katarína; Turisová, Ingrid; Turis, Peter; Smatanová, Janka; Zozomová-Lihová, Judita
Accurate species delimitation is essential for understanding biodiversity and evolutionary processes, yet it remains challenging in taxonomically complex groups shaped by recent divergence and reticulate evolution. Nevertheless, such groups offer unique insights into the earliest stages of speciation and its driving forces. The genus Erysimum (Brassicaceae), notable for its karyological diversity and high endemism, represents an excellent model for such studies. Here, we investigated the E. odoratum complex, encompassing up to 10 recognized species in the Carpathians and western Balkans, to test its monophyletic origin, clarify species boundaries and elucidate the main drivers of diversification. We combined cytotype screening (chromosome counting and flow cytometry), morphometric analysis, and two high-throughput sequencing methods: RADseq, to resolve phylogenetic relationships as well as to detect fine-scale genetic structure and introgression; and target enrichment (Hyb-Seq), to elucidate polyploid origins. Our results demonstrate that the studied complex is polyphyletic, and we focused on the lineage comprising E. odoratum s.str. and Carpathian species. Phylogenomic data from the Carpathians contradict traditional taxonomy, which recognized up to four diploid endemics, and instead support a single species, E. witmannii with geographically structured genetic variation. Within E. odoratum s.str., we identified multiple polyploid cytotypes resulting from independent auto- and allopolyploidization events, although disentangling parental subgenomes, ancestral polymorphisms, and introgression remains difficult. We propose that diversification in this species complex has been driven by a combination of allopatric divergence and reticulate evolution (involving both introgression and allopolyploidy), further shaped by chromosomal dynamics such as dysploidy.
Iron and manganese oxides from the oxidation zone of the Ľubietová-Podlipa deposit
(Univerzita Komenského v Bratislave, 2025) Majzlan, Juraj; Števko, Martin; Chovan, Martin; Milovská, Stanislava; Jeleň, Stanislav; Mikuš, Tomáš; Biroň, Adrián
Ľubietová-Podlipa is a small historical Cu deposit in the Veporic unit of the Central Western Carpathians in Slovakia. It is the type locality of libethenite and mrázekite. The oxidation zone of the deposit contains copious pseudomalachite and malachite that attracted the attention of mineralogists and mineral collectors for a long time. Another abundant group of supergene minerals, Fe and Mn oxides and oxyhydroxides (collectively called oxides here), received much less attention and were investigated closely in this work. Bulk analyses of the oxidation zone (channel samples) showed that it is rich in Cu (average 7070 ppm), Mn (430), Zn (650), Ba (640), Bi (235). Concentrations of other elements are low, such as Co (49), Ni (47), Sb (47), W (96), or Ag (1.2). Some of the elements are concentrated by Mn oxides. The Fe and Mn oxides formed mostly by weathering of chalcopyrite and Fe-dolomite. They coat the Cu minerals but may also be the substrate for the growth of the Cu minerals. The Mn oxides are flaky, with individual particles less than 5 mm large and less than 1 mm thick. The particles accumulate in spherical aggregates with size of tens of micrometers. Raman spectroscopy and powder X-ray diffraction indicate that the Mn oxides are most likely mixtures of birnessite and asbolane, with minor amount of tectomanganates (e.g., hollandite). They accumulate CuO (average of electron microprobe analyses 21.8 wt.%), CoO (5.5), BaO (1.0), CaO (0.5), and K2O (0.5) in their structure. Fe oxides occur either as brick-red, massive pseudomorphs after chalcopyrite or as coatings and crusts on fractures. They were identified as hematite or goethite, commonly intergrown. Hematite crystals may be embedded in pseudomalachite and Fe and Mn oxides intergrown in tufts. Fe oxides adsorbed As, Sb, and Bi, when available, but the concentrations of these elements are usually low (< 1.5 wt.%). Fe oxides may be rich in P2O5 (average 2.78 wt.%), SiO2 (1.67), Al2O3 (0.22), and CuO (6.47). Locally elevated Bi concentrations led to precipitation of rare bismutite. Because of their abundance and retention capacity for certain elements, Fe and Mn oxides influenced the composition of the oxidation zone and the environmental mobility of the elements to a great extent.
Vybrané výsledky riešenia projektu VEGA: Vplyv vybraných faktorov na kvalitatívno-kvantitatívne charakteristiky drevného prachu v pracovnom ovzduší pri opracovaní dreva elektrickým ručným náradím
(Belianum. Vydavateľstvo Univerzity Mateja Bela v Banskej Bystrici, 2025) Kučerka, Martin; Očkajová, Alena
Projekt vychádzal z poznania, že drevný prach má toxické účinky a jemné častice nachádzajúce sa vo vzduchu pri opracovaní dreva predstavujú významné zdravotné riziko pre zamestnancov. Ich dlhodobé vdychovanie je pre ľudský organizmus nebezpečné, keďže súvisí s dráždením dýchacích ciest, poškodením funkcie pľúc a zvýšeným karcinogénnym rizikom. Z dôvodu karcinogenity drevného prachu je nevyhnutné pravidelne monitorovať a predovšetkým minimalizovať jeho koncentráciu v pracovnom prostredí. Cieľom projektu bolo zistiť významnosť vplyvu vybraných faktorov - technologických parametrov a fyzikálno-mechanických vlastností dreva na kvalitatívno-kvantitatívne charakteristiky častíc drevného prachu vzniknutého pri opracovaní dreva v praxi bežne používanými ručnými elektrickými strojmi. Projekt bol koncipovaný tak, aby v reálnom čase sledoval tvorbu pevného aerosólu pri procesoch pílenia, brúsenia a frézovania rastlého dreva a MDF dosiek. Získané výsledky tvoria databázu poznatkov pre tvorbu analytických modelov zohľadňujúcich vplyv jednotlivých faktorov na vlastnosti drevného prachu a zároveň budú napomáhať drevárskym podnikom na Slovensku, ktoré dlhodobo čelili problémom s prašnosťou pracovného ovzdušia. Projekt mal ambíciu podporiť efektívnejšie plnenie legislatívnych požiadaviek v oblasti hodnotenia a riadenia rizík spojených s expozíciou drevnému prachu.
Technická súťaž žiakov základných škôl v Banskej Bystrici
(Belianum. Vydavateľstvo Univerzity Mateja Bela v Banskej Bystrici, 2025) Kvasnová, Petra; Kováčik, Vladimír; Pavlovkin, Ján
Článok opisuje organizáciu, priebeh a výsledky Technickej súťaže žiakov základných škôl z Banskej Bystrice a Zvolena. Súťaž pozostávala z teoretickej a praktickej časti. Súťaž organizoval Klub AMAVET 937 (Asociácia pre mládež, vedu a techniku) v spolupráci s Územným koordinačným centrom Zväzu slovenských vedecko technických spoločností. The article describes the organization, course and results of the Technical Competition of primary school pupils from Banská Bystrica and Zvolen. The competition consisted of a theoretical and practical part. The competition was organized by the Club AMAVET 937 (Association for Youth, Science and Technology) in cooperation with the Territorial Coordination Center of the Union of Slovak Scientific and Technical Societies.
AMAVET - Krajské kolo Festivalu vedy a techniky v Banskej Bystrici
(Belianum. Vydavateľstvo Univerzity Mateja Bela v Banskej Bystrici, 2025) Kvasnová, Petra; Pavlovkin, Ján
Autori článku prezentujú projekty žiakov základných a stredných škôl, ktoré boli prezentované v rámci krajského kola Festivalu vedy a techniky usporiadaného Asociáciou pre mládež, vedu a techniku klub 937 so sídlom Kremnička 10 v Banskej Bystrici. Prezentujúci žiaci základných a stredných škôl v Banskobystrickom kraji preukázali svoje vedomosti a zručnosti pri riešení rôznych projektov. Všetky projekty sú originálne. Originalita ako jeden z faktorov tvorivosti je významná pri ďalšom rozvoji kreativity žiakov základných a stredných škôl. Prezentované a hodnotené projekty sú aplikovateľné v praxi. The authors of the article present the projects of primary and secondary school pupils, which were presented as part of the regional round of the Festival of Science and Technology organized by the Association for Youth, Science and Technology club 937 with its registered office in Kremnička 10 in Banská Bystrica. The presenting pupils of primary and secondary schools in the Banská Bystrica Region demonstrated their knowledge and skills in solving various projects. All projects are original. Originality as one of the factors of creativity is important in the further development of creativity of primary and secondary school pupils. The presented and evaluated projects are applicable in practice.

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