06 Príspevky v zborníkoch

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7000 years of environmental change in the Eastern Carpathians: A palynological record from Lake Vinderel
(Univerzita sv. Cyrila a Metoda v Trnave, 2025) Bartóková, Silvia; Kiapešová, Barbora; Trnková, Katarína
Lake Vinderel, located in the high-altitude Maramureș Mountains of the Romanian Carpathians, provides a valuable archive of paleoecological and climatic changes. This study aimed to reconstruct the lake’s paleoecological history over the past ~7,000 years and to identify the onset and development of anthropogenic influence in the surrounding landscape. A sediment core was extracted using a Uwitec Piston Corer, and palynological analysis was performed on 66 samples (0.5 cm³ each) using standard acetolysis and light microscopy at 400× magnification. The resulting pollen diagram includes 53 identified taxa and reveals several key phases in vegetation dynamics. In the earliest period, the region was dominated by forest vegetation composed mainly of Pinus, Abies, Betula, and Corylus, indicating stable mid-Holocene climatic conditions. A continuous and abundant presence of Alnus and grass taxa (Gramineae) suggests a wetter phase, potentially marking the onset of human influence. In later stages, a significant increase in non-arboreal taxa such as Gramineae, Artemisia, and Aster-type points to intensified anthropogenic impact, including deforestation and land-use changes. This study enhances understanding of long-term interactions between climate, vegetation, and human activity in the Carpathians and enriches the palynological record of rare and ecologically sensitive mountain taxa.
A multi-proxy survey of recent environmental changes from the sediments of lake Apastapeque (El Salvador, Central America)
(Stockholm University, Sweden, 2018) Wojewódka, Marta; Hamerlík, Ladislav; Krahn, Kim; Zawisza, Edyta; Cohuo Duran, Sergio; Macario-Gonzalez, Laura; Hoelzman, Philipp; Rose, Neil L.; Yang, Handong; Charqueño- Celis, Fernanda; Schwalb, Antje; Pérez, Liseth
Analytical evaluation of PAH degradation during the cultivation of hydrocarbon-utilizing bacteria with bioremediation potential
(Univerzita Pavla Jozefa Šafárika v Košiciach, 2025) Kupcová, Elena; Ševčíková, Janka; Krempaská, Vladimíra; Vesteg, Matej; Murgašová, Michaela; Guziurová, Pavlína
Polycyclic aromatic hydrocarbons (PAHs) are persistent environmental pollutants characterized by high toxicity and low biodegradability [1]. In this study, bacterial strains capable of utilizing PAHs [2,3] were isolated from various extreme environmental habitats. The isolates were cultivated in mineral media supplemented with selected PAHs (specifically fluorene and phenantrene) as the sole carbon source and exposed to a range of concentrations to determine the maximum levels that the bacteria were able to utilize. The degradation efficiency was assessed by monitoring the residual concentrations of the target compounds using high-performance liquid chromatography with diode array and fluorescence detection (HPLC-DAD/FLD). The results revealed that several bacterial strains exhibited a remarkable ability to degrade specific PAHs even at elevated concentrations, highlighting their potential application in bioremediation of contaminated environments.
Bacterial inhabitants of wood-decay fungi basidiocarps
(Univerzita sv. Cyrila a Metoda v Trnave, 2025) Beck, Terézia; Vesteg, Matej; Ševčíková, Janka; Kureková, Janka; Pristaš, Peter
Various bacteria were isolated from 14 basidiocarps of wood-decay fungi collected from June to September 2023 in selected locations in Slovakia (Oravské Veselé village, Banská Bystrica city, and a mixed forest in Vrútky city). Fungi were identified by combination of morphological traits and ITS spacer region sequence analysis, bacteria were identified by MALDI-TOF MS. To detect the cellulolytic ability of bacterial isolates, the Congo-Red Staining method with carboxymethyl cellulose medium was used. Highly variable populations of bacteria were detected in all basidiocarps with predominance of Pseudomonas spp. Most basidiocarps (9) were identified as Phellinus igniarius, from which multiple Pseudomonas spp. including P. extremorientalis, P. synxantha, two Achromobacter spp., Bacillus pumilus, B. subtilis, Enterobacter asburiae, E. bugandensis, Ewingella americana, Lelliottia amnigena, Serratia liquefaciens, and Stenotrophomonas sp. were isolated. From Trametes versicolor basidiocarps, Ochrobactrum sp. and Lelliottia amnigena were isolated; from Trametes gibbosa, Bacillus sp., Bacillus subtilis, Lysinibacillus fusiformis, two Pseudomonas spp., and Stenotrophomonas sp.; from Trametes hirsuta, three different Pseudomonas species and Raoultella terrigena were isolated. In Fomitopsis betulina, two Bacillus spp. and Sporosarcina sp. were detected. Cellulolytic activity was observed in bacteria belonging to the Pseudomonas, Bacillus, and Achromobacter genera. The possible role of fungi-bacteria symbiosis in wood-decay is discussed.
Bezstavovce viazané na vodu očami žiakov: vnímanie a ochota ich chrániť
(Trnavská univerzita v Trnave, 2025) Bartóková, Silvia; Prokop, Pavol
Vodné bezstavovce zohrávajú kľúčovú úlohu v ekosystémoch, avšak často zostávajú na okraji záujmu verejnosti a ochrany prírody, čo je spôsobené ich nízkou známosťou a obmedzenou vizuálnou príťažlivosťou. Posilnenie povedomia o ekologickej hodnote vodných bezstavovcov a ich spojení s ekosystémovými službami môže zvýšiť empatiu a podporiť hlbšiu ochotu chrániť tieto druhy. Táto štúdia sa zameriava na vnímanie menej známych vodných a na vodu viazaných druhov medzi žiakmi základných škôl, pričom analyzuje ich estetickú príťažlivosť a ochotu zapojiť sa do ochranárskeho úsilia. Zistili sme, že medzi vnímanou atraktívnosťou vodných bezstavovcov a ochotou žiakov ich chrániť je signifikantná korelácia; najatraktívnejšie sú hodnotené imága vážok (Odonata), mäkkýše (Molusca) sú vnímané v oboch prípadoch neutrálne a medzi najmenej atraktívne patria korčuliarka obyčajná (Gerris lacustris) a pijavica lekárska (Hirudo medicinalis). Za pomoci rozličných praktických úloh, vizuálnych materiálov a emocionálne angažujúcich metód realizovaných v rámci záujmových krúžkov so žiakmi základných škôl, je snaha preklenúť priepasť medzi nízkou verejnou informovanosťou a nevyhnutnosťou ochrany ekologicky významných, no prehliadaných druhov.
Bio-Survivor: Who Does It Better - Biobased Polymers or Microbial Consortia of the Baltic Sea?
(Wydawnictwo Uczelniane Zachodniopomorskiego Uniwersytetu Technologicznego w Szczecinie, 2025) Guziurová, Pavlína; Krempaská, Vladimíra; Sedláček, Petr; Sedlár, Karel; Obruča, Stanislav
As most plastic waste ends up in the sea, the marine industry is looking for sustainable alternatives to conventional plastics and bio-based polymers are being explored for use in equipment and components. However, their long-term stability in the ocean remains uncertain - especially if these materials are lost or dumped at sea. This study evaluates the resistance of these biobased polymers – namely poly(3- hydroxybutyrate) (PHB), poly(butylene succinate) (PBS) and poly(lactic acid) (PLA) – to degradation by marine microbial consortia from the Baltic Sea. The aim was to assess whether the materials could be degraded in marine environment by the sea microbial consortia, which could limit their durability and raise environmental concerns. Initial screening of degrading ability of the microorganisms was performed using agar plate tests with emulsified polymers to detect the formation of halozones. To better investigate the degradability, the polymer samples of solid polymers in granular or foil form (prepared by hot pressing or solvent casting) were exposed to microbial consortia. The structural changes were investigated by scanning electron microscopy (SEM), while the chemical and physical changes were monitored by differential scanning calorimetry (DSC) and gel permeation chromatography (GPC/SEC-MALS). The bacterial growth was monitored by optical density (OD) measurements and the corresponding bacterial strains were identified by MALDI-TOF and DNA sequencing. The results show that some bacteria naturally present in the Baltic Sea are able to degrade some biobased polymers. This suggests that if these materials enter the marine environment, they may not remain intact, which may not cause 'ghost fishing' if equipment is lost. While their biodegradability may provide environmental benefits in the case of waste, it may also pose a risk for long-term use in marine equipment if the materials are susceptible to microbial attack.
Bioavailability of potentially toxic elements in selected Cu-deposits of Europe
(Nitrianske Pravno Ústav geotechniky Slovenskej akadémie vied : Košice, 2024) Andráš, Peter; Midula, Pavol; Ševčíková, Janka; Šuránek, Matej; Matos João Manuel, Xavier; Janštová, Jana; Buccheri, Giuseppe; Tomaškin, Ján; Drímal, Marek
Bioavailability of potentially toxic elements from four dump-field material at several abandoned European Cu-deposits: Špania Dolina (Slovakia), Caporciano and Libiola (Italy) and São Domingos (Portugal) was studied. The three steps sequential analyse study show some relation among geological setting and mineralogical composition of ores vs. bioavailability of metals. The best bioavailable metals at first three mentioned deposits are Cu and Cd (in one case, atr São Domingos As and Co). The results confirmed that the geological setting substantially influence the order of the bioavailability.
Biodostupné formy potenciálne toxických prvkov v antropogénnej pôde odvalu rudného ložiska Cínovec
(Štátny geologický ústav Dionýza Štúra Bratislava, 2024) Midula, Pavol; Svobodová, Sára; Andráš, Peter; Ševčíková, Janka; Tomaškin, Ján
Bokashi composting as an alternative method of processing biodegradable kitchen waste in households
(Univerzita sv. Cyrila a Metoda v Trnave, 2025) Ševčíková, Janka; Laceková, Karolína; Murgašová, Michaela; Beck, Terézia; Vesteg, Matej
The study focuses on the application of Bokashi composting as an alternative method of biodegradable kitchen waste (BKW) management in households. A questionnaire survey conducted in the Lučenec district aimed to assess residents’ willingness to separate BKW and their interest in alternative processing methods. The Bokashi composter uses anaerobic fermentation to transform waste into solid residues and fermentation liquid. The effectiveness of this liquid was tested via a phytotoxicity test using garden cress seeds (Lepidium sativum L.), observing germination effects at various dilutions over 48 hours. Results showed that 38.9% of respondents would prefer home composting with provided composters, and 61.1% consider it the most efficient method of BKW management. While 50% had not heard of the Bokashi method, 22.2% expressed interest in further information. Findings suggest a significant potential for domestic composting, especially when proper technical support and education are provided. The phytotoxicity test confirmed that the fermentation liquid is suitable for gardening use when adequately diluted.
Composition of cladoceran (Crustacea) and chironomid (Diptera: Chironomidae) and assemblages from surface sediments of Central American lakes
(SIL, Merida, Mexico, 2017) Wojewódka, Marta; Hamerlík, Ladislav; Zawisza, Edyta; Sinev, A. Y.
Cybersecurity by design: Modeling processes first
(Univerzita sv. Cyrila a Metoda v Trnave, 2025) Siládi, Vladimír; Randlisek, Miroslav
Universities are increasingly exposed to cybersecurity threats focused on personal data, research information, and IT service availability. Their open, decentralized environment, characterized by academic freedom, also increases vulnerability to cyber-attacks and internal security weaknesses. Effective cybersecurity management in this context requires structured, transparent, and coordinated processes that respect the specific characteristics of academic life. Business process modeling (BPM) can serve as a practical tool to document, improve, and communicate key security- related activities. This contribution explores how BPM tools can support cybersecurity process management in universities. Specifically, it compares two modeling tools OpenBPM and ADONIS, in terms of their usability and effectiveness for visualizing selected processes related to university cybersecurity. The focus is not on the tools themselves, but on whether process clarity plays a more significant role than the tool choice. This contribution aims to share practical experience by comparing the usability of BPM tools in supporting university cybersecurity managers in balancing academic freedom with effective security management.
Determination of microbial isolates from two different composts and the evaluations of their potency to stimulate the growth of tomato
(Univerzita sv. Cyrila a Metoda v Trnave, 2025) Murgašová, Michaela; Krempaská, Vladimíra; Beck, Terézia; Ševčíková, Janka; Vesteg, Matej
Composting is an aerobic process consisting of several phases, producing a stable and mature fertiliser. The first compost analysed in this study originates from the municipal composting plant, which serves for decomposition of kitchen waste, while the second compost is being commercially sold. The aim of this study was to isolate bacteria promoting plant growth from both composts. Samples from composts were incubated at 25 °C in various liquid cultivation media. Subsequently, selected colonies were inoculated onto fresh solid media and the bacterial composition of both composts was analyzed by MALDI TOF-MS after protein extraction. We were able to isolate several interesting bacterial species including Lysinibacillus xylanilyticus and Solibacillus silvestris from municipal compost. Pseudomonas citronellolis and Pseudomonas stutzeri were isolated from the commercially sold compost. These isolates have traits that are specific for plant-growth promoting bacteria or they can serve as biocontrol agents against infections causing many plant diseases. Isolates with these traits can thus significantly facilitate the growth, development or immunodefence of tomato (Solanum lycopersicum L.).
Distribúcia chemických prvkov vo výplni amygdaloidných dutín (achátov) v permských bazaltoch, Malužiná-Svidovo (Hronikum, Západné Karpaty)
(Masarykova univerzita : Brno, 2026) Antalík, Filip; Ferenc, Štefan; Šimonová, Viera
Diversity of psychrophilic bacteria isolated from cold alpine lakes in High Tatras, Slovakia
(University of Belgrade, 2025) Krempaská, Vladimíra; Vesteg, Matej
Psychrophilic bacteria are adapted to thrive at low temperatures through specialized cellular mechanisms, including the production of cold-active enzymes, antifreeze proteins and modified membrane lipids. These traits make them promising candidates for biotechnological applications in cold-chain industrial processes, biodegradation of pollutants in cold ecosystems and bioremediation of contaminated areas under low-temperature conditions. This study explores the bacterial diversity in selected glacial lakes of High Tatras, Slovakia, with a focus on the isolation and characterization of psychrophilic microorganisms with potential biotechnological applications. Water and sediment samples were collected from five alpine lakes and cultured at two temperatures 20 °C and 4 °C to differentiate. Using MALDI-TOF mass spectrometry, 107 bacterial isolates were identified. At 20 °C, the predominant genera included Serratia, Bacillus and Pseudomonas, with a notable abundance of potentially pathogenic Enterobacteriaceae in Slavkovské pleso, suggesting anthropogenic influence. In contrast, cultivation at 4 °C yielded a distinct spectrum of psychrophilic taxa, including Pseudomonas antarctica, Exiguobacterium sibiricum and Janthinobacterium lividum — species known for their ecological resilience and functional potential in cold environments. The observed microbial profiles also provide insights into how environmental and anthropogenic factors shape microbiome composition in fragile alpine ecosystems. By highlighting the functional traits of psychrophiles, this work contributes to the broader understanding of microbiome adaptation, resilience and their prospective use in sustainable biotechnology.
Effect of grain direction on particle size distribution during sanding of spruce, beech and oak wood
(University of Warsaw, 2025) Kučerka, Martin; Očkajová, Alena
This paper focusses on the impact of the direction orientation of the sanding of selected wood types on the particle size distribution. In the experiment, a hand-held GBS 100 AE belt sander was used, with particles obtained through two sanding models: at angles of 0 ° and 90 ° with respect to the wood structure. The study examined the effects of cutting orientation on the particle size distribution in beech, oak and spruce wood sawdust. Statistical analysis was used to characterise the particle size distribution, and a combination of orientations was compared for each type of wood. Statistical analysis revealed significant differences in the particle size distribution between the two cutting orientations, with p-values of 0.018 and 0.0002 for beech and spruce, respectively. On the contrary, oak did not show minimal statistically significant differences between orientations (p = 0.912). The results highlight the crucial role of the wood microstructure in determining the effect of cutting orientation on particle morphology. Specifically, spruce showed the highest sensitivity to orientation changes, while oak remained relatively stable in different cutting directions.
Energetický potenciál a zásoby uhlíka horských lúk
(Ústav ekológie lesa SAV : Nitra, 2025) Kizeková, Miriam; Britaňák, Norbert; Čunderlík, Jozef; Hanzes, Ľubomír; Pollák, Štefan; Vargová, Vladimíra; Jančová, Ľubica; Kanianska, Radoslava
Mountain meadows 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 Oversown grasslands) in 5 mountain ranges (Great Fatra Mts., Low Tatra Mts., Slovak Paradise Mts., Čergov Mts., Slánské Hills Mts.) of the Western Carpathians in Slovakia. The results showed that the total carbon stock of the mountain meadows equal to 2.120 x 103 tons. The calculated biomethane production ranged from 6,606 GJ in the Slovak Paradise Mts., to 122,888 GJ in the Low Tatra Mts., which had the largest area of grassland habitats. The theoretical energetic potential exceeded 1,139 x 103 GJ.
Experimental verification of the performance of the iEDF scheduling algorithm for IoT tasks in an Edge cloud system
(Univerzita sv. Cyrila a Metoda v Trnave, 2025) Hamada, Adrián; Škrinárová, Jarmila
The aim of this paper is to verify the performance of the iEDF (improved Earliest Deadline First) algorithm that we designed and implemented. It is the algorithm that schedules IoT tasks in an Edge cloud system. We verify the performance of the algorithm based on 2 key criteria: makespan (the completion time of the last task in the schedule) and deadline fulfilment (the latest required completion time) of each task. We designed experiments, implemented 3 scheduling algorithms in the CloudSimPlus simulator environment: our iEDF, the original EDF and a Greedy-based algorithm and used 33 scaled datasets of IoT tasks. Together we obtained 99 pseudo-optimal schedules for various scaled datasets of tasks using the whole set of microclouds and by applying all 3 scheduling algorithms. This provided us with a detailed picture of the behaviour of the scheduling system when using different input sets. On the base of performed complex experiments and by mutual comparing of algorithms, we found that our algorithm iEDF achieves the shortest (best) makespan and 100% deadline fulfilment for all scheduled tasks. The Greedy-based algorithm had slightly worse makespan results and insufficient deadline fulfilment. The EDF algorithm had slightly worse deadlines (83 to 100%) and the worst makespans among the compared algorithms.
Fuzzy relations in some decision-making and expert systems
(Ostravská univerzita v Ostravě, 2026) Bruteničová, Michaela
Geochemický model transformácie gabra na rodingit
(Štátny geologický ústav Dionýza Štúra Bratislava, 2024) Butek, Juraj; Spišiak, Ján; Fabre, Sébastien; Duchene, Stéphanie; Grégoire, Michel
Improvise. Adapt. Overcome - Baltic Sea Bacteria and Their Polymer Degrading Ability
(Universidade NOVA de Lisboa, 2025) Guziurová, Pavlína; Krempaská, Vladimíra; Sedláček, Petr; Sedlár, Karel; Obruča, Stanislav
As plastics production and consumption today continue to contribute to petrochemical plastic pollution, greener packaging alternatives such as biopolymers and biobased compostable materials are becoming a major focus of research. However, these materials can also pose environmental problems in areas lacking the appropriate degradation conditions. Despite global recycling efforts, plastics frequently end up in landfills and in natural environments such as seas and oceans. Several studies have reported significant microplastic pollution in the Baltic Sea; therefore, the diversity of microorganisms present in these waters may indicate the existence of enzymatic systems capable of degrading polymeric packaging materials. In this study, several tests were conducted to evaluate the degradation capabilities of bacteria isolated from the Baltic Sea on different types and forms of biobased polymers. The formation of halozones was observed and confirmed using agar plate assays with emulsified polymers – poly(3-hydroxybutyrate), poly(butylene succinate) and poly(lactic acid). Selected polymers in granule or film form (prepared via hot pressing or solvent casting methods) were exposed to the bacterial consortium, and material property changes were monitored. Major structural changes were observed using scanning electron microscopy (SEM), while physicochemical property changes were analyzed using differential scanning calorimetry (DSC) and gel permeation chromatography (GPC-SEC/MALS). Additionally, biochemical activity was assessed by measuring biological oxygen demand (BOD) and the optical density (OD) of microbial cultures. Microbial consortium was separated and analysed on MALDI-TOF and sequenced. The results indicate that certain bacteria exhibit potential to for the biodegradation of various polymers. Further research will examine these microorganisms in more detail in future studies.

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