08 Články v časopisoch

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Čo sa môžeme naučiť z (paleo)limnologického výskumu jazier Strednej Ameriky?
(Limnologický spravodajca, Slovak Limnological Society, 2017-02) Hamerlík, Ladislav
Sub-fossil Chironomidae (Diptera) from lake sediments in Central America: a preliminary inventory
(Zootaxa, Magnolia press, 2018) Hamerlík, Ladislav; Da Silva, Fabio Laurindo; Wojewódka, Marta
The chironomid diversity of Central America is virtually underestimated and there is almost no knowledge on the chironomid remains accumulated in surface sediments of lakes. Thus, in the present study we provide information on the larval sub-fossil chironomid fauna from surface sediments in Central American lakes for the first time. Samples from 27 lakes analysed from Guatemala, El Salvador and Honduras yielded a total of 1,109 remains of four subfamilies. Fifty genera have been identified, containing at least 85 morphospecies. With 45 taxa, Chironominae were the most specious and also most abundant subfamily. Tanypodinae with 14 taxa dominated in about one third of the sites. Orthocladiinae were presented by 24 taxa, but were recorded in 9 sites, being dominant in only one site. Podonominae were collected only in one locality. Head capsules of Heterotrissocladius found in the high elevation lake Magdalena, Guatemala, represent a first record for the Neotropical region. Both relative abundance and species richness of Chironominae and Orthocladiinae showed significant relationship to elevation, while Tanypodinae were indifferent. Hopefully, the list of taxa provided by our study will be a base line for future limnological and paleolimnological investigations using chironomid remains in the region.
Subfossil Chironomidae (Diptera) in surface sediments of the sinkholes (cenotes) of the Yucatan Peninsula: Diversity and distribution
(Vydavateľstvo PAGEPress, 2018) Hamerlík, Ladislav; Wojewódka, Marta; Zawisza, Edyta; Cohuo Duran, Sergio; Macario Gonzalez, Laura; Pérez, Liseth; Szeroczyńska, Krystyna
Cenotes (sinkholes), formed by the dissolution of the carbonate rock, are the most common waterbodies on the Yucatan Peninsula. Despite their unique features and great amount in the region, our knowledge on the biota of cenotes remains fragmentary. Within the present study we analysed chironomid remains from surface sediment of ten cenotes situated in SE Mexico. In total, 20 taxa of 17 genera were recorded, and the total diversity was estimated to ~30 taxa. The most common taxa were Polypedilum (Tripodura) sp., Tanytarsus ortoni-type, Fittkauimyia sp., Labrundinia sp. and Endotribelos sp. There was a great variability in head capsule abundance among cenotes, ranging from 1 to 64 individuals per site with significantly higher number of remains recorded in open cenotes compared to the closed, cavern types. The results indicate that beside ecological features, such as low trophy, oxygen depletion, simplified habitat structure and fish predation, there are also taphonomical processes connected to the specific nature of cenotes that can hinder the accumulation of biological remains in the sediment. We conclude that due to poor sedimentation and preservation of remains, cenotes have limited potential for palaeolimnological studies.
First record of the genus Heterotrissocladius (Chironomidae: Orthocladiinae) from the Neotropical Region
(NTNU University Museum, Norway, 2018) Hamerlík, Ladislav; Da Silva, Fabio Laurindo
Here we report the occurrence of Heterotrissocladius (Diptera: Chironomidae: Orthocladiinae) for the first time in Central America, as well as in the Neotropical region. The report is based on sub-fossil chironomid head capsules from surface sediments of a high elevation lake, Lago Magdalena, Guatemala.
Chironomidae (Insecta: Diptera) of Ecuadorian high altitude streams: a survey and illustrated key
(Florida Entomological Society, 2018) Hamerlík, Ladislav; Da Silva, Fabio Laurindo; Jacobsen, Dean
Chironomidae (Diptera) are among the most diverse and widespread aquatic insects, with roughly 5,500 described species inhabiting an enormous variety of aquatic ecosystems, ranging from moist soils to lakes and rivers, and even marine ecosystems. Despite its ubiquity, the group remains underrepresented in studies addressing aquatic insect assemblages of high-altitude systems, either glacier-fed or non-glacial, particularly in South America. Glacier-fed streams possibly are one of the harshest ecosystems in nature, and present a distinct downstream pattern in species distribution and diversity away from the constraining influence of the glacier. In this context, the goal of our study was to provide data on the chironomid fauna of glacier-fed streams, together with neighboring non-glacial streams in Ecuador, in order to contribute to the overall knowledge of tropical fauna in high Andean regions. Also, we sought to provide an identification key and photography material for future studies. Collections of non-biting midges were made in Ecuador during Jan 2008. In total, 1,412 specimens belonging to 16 genera and at least 23 species within the subfamilies Chironominae (3 taxa), Diamesinae (3 taxa), Podonominae (3 taxa), Orthocladiinae (13 taxa), and Tanypodinae (1 taxon) were found. The subfamilies Podonominae and Orthocladiinae predominated in terms of abundance. Parochlus was the most widespread genus of Chironomidae, while Cricotopus was the most diverse. This study contributes to the knowledge of the chironomid fauna in the high-altitude streams in Ecuador, and hopefully will motivate further studies in the area.
Historicko-geografická analýza extrémov počasia v prvej polovici 18. storočia (v dobe Mateja Bela) na území Slovenska
(Inštitút histórie Filozofickej fakulty Prešovskej univerzity : Prešov, 2024) Hronček, Pavel; Hrončeková Gregorová, Bohuslava
Historical-geographical analysis of weather extremes in the first half of the 18 th century (the time of Matej Bel) on the territory of Slovakia. The study presents a historical-geographical analysis of the weather and its extreme impacts in the landscape, its effects on the economy and human life in the period of the first half of the 18th century, which is also referred to as the era of Matej Bel. Chronologically reconstructs these events on the territory of Upper Hungary, i.e. j. the territory of today’s Slovakia. The subject of the research were all events that deviated from the long-term course of the weather in a given period - extreme frosts, snow calamities, thunderstorms, lightning strikes, windstorms, floods, droughts, etc. The weather in the studied period was strongly influenced by the most extreme period within the Little Ice Age, which lasted in the Western Carpathians from about the 15th century to the middle of the 19 th century. It was called the Maunder Minimum (1645–1715) and was characterized by a significant decrease in solar activity. This led to significant cooling and the emergence of extreme situations and weather instability. Weather extremes were also described by Matej Bel in his work called „Notitia“. He focused directly on the events he experienced in his life and on his travels - heavy snow cover in the mountains, frosts, storms, floods, droughts, etc.
Trends and practices in college cybersecurity
(Západočeská univerzita v Plzni, 2024) Štefánik, Andrej; Kučerka, Martin
The introduction of modern technology into the academic environment brings with it not only new opportunities but also an increased risk of cyber-attacks. Universities now find themselves on the front line of defense against increasingly sophisticated threats to the integrity of their information systems and the confidentiality of academic data. This paper focuses on current trends and challenges in cybersecurity in higher education. We analyze the various strategies that universities are adopting to protect their IT infrastructures, including carefully tuning existing technologies, implementing new security solutions, and changing the security awareness of all stakeholders – students, employees, and management.
Červený zoznam cicavcov Slovenska
(Štátna ochrana prírody Slovenskej republiky : Banská Bystrica, 2024) Urban, Peter; Ambros, Michal; Kadlečík, Ján; Černecký, Ján; Kocianová-Adamcová, Marcela; Baláž, Ivan; Bučko, Jozef; Finďo, Slavomír; Krojerová, Jarmila; Kubala, Jakub; Lehotská, Blanka; Uhrin, Marcel
Red Lists of threatened species are a respected source of information on the threat status of animal, plant and fungal species. They analyse the extinction risk of species, applying the standard categories and criteria. The structure of the current Slovakian Red List of Mammals reflects actual standard IUCN criteria and categories at both the global and regional levels. Of the 96 mammalian species of Slovakia (where the chamois is represented by two subspecies: autochtonous endemic Rupicapra rupicapra tatrica and the introduced R. r. rupicapra) we evaluated 86 (88.7%), the other 11 non-native and introduced taxa (11.3%) were not evaluated (NE). Twenty nine (33.7%) of the evaluated species are categorised as threatened. One species (Marmota marmota latirostris) was assessed as “Critically Endangered” (CR). Seven (8.1%) taxa (Spermophilus citellus, Alexandromys oeconomus mehelyi, Rhinolophus euryale, Miniopterus schreibersii, Lynx lynx, Bos bonasus, Rupicapra rupicapra tatrica) meet the criteria for the “Endangered” (EN) category. In the category “Vulnerable” (VU) 21 (24.4%) taxa were included (Microtus tatricus, Sorex alpinus, Rhinolophus ferrumequinum, Rhinolophus hipposideros, Myotis bechsteinii, Myotis blythii, Myotis brandtii, Myotis dasycneme, Myotis emarginatus, Myotis myotis, Eptesicus nilssonii, Eptesicus serotinus, Nyctalus lasiopterus, Nyctalus leisleri, Nyctalus noctula, Barbastella barbastellus, Plecotus auritus, Plecotus austriacus, Vespertilio murinus, Felis silvestris, Lutra lutra). Mustela lutreola has become extinct in the territory of the country (“Regionally Extinct” – RE). The Red List also includes eleven species classified as “Data Deficient” (DD) due to the lack of data.
Using 3D print in student projects
(Západočeská univerzita v Plzni, 2024) Tadialová, Alžbeta; Kvasnová, Petra
Technology plays a key role in education, with 3D printing being one of the most innovative methods for developing technical skills and creativity in students. This article presents a student project focused on the design and production of cookie cutters for baking using 3D printing. The procedure includes steps from creating a design in vector software to modifying the model in a 3D environment to printing the final product itself. Students learn the basics of 3D modeling, master the practical challenges of printing, and deepen their technical thinking, project planning, and problem-solving skills. The result is a unique product and experience with digital technologies.
Petroarchaeological study of medieval ruins of Bzovík fortified monastery
(North University of Baia Mare, 2024) Andráš, Peter; Spišiak, Ján
The article represents the results of the complex petroarcheological study focused on the building material with respect to the restoration of the old fortified monastery Bzovík (Central Slovakia). The aim of the study was to determine the original building material and to suggest the best solutions of the building recovery. The petroarcheological study enabled to describe the present state of the used rocks, their resistance and several types of mortars. The aim of the study was determining the material of building We found that the majority of the building stones are from the Neogene volcanics of the Štiavnica stratovolcano. Mainly effusive and extrusive activity of andesite volcanism. Distinguish the original and more new additional building elements, suggest suitable procedures and materials with respect to the sanitation of the building complex.
Maldonite (Au2Bi) from hydrothermal U-As mineralization near Henclová (Spišsko-gemerské rudohorie Mts., Western Carpathians): the first occurrence in Slovakia
(Mgr. Jiří Sejkora : Praha, 2024) Ferenc, Štefan; Kopáčik, Richard; Števko, Martin; Mikuš, Tomáš
In Slovakia, maldonite was identified in the hydrothermal vein with U-sulphidic ore mineralization near Henclová village (Gelnica district) in the Spišsko-gemerské rudohorie Mts. (Vlachovo Formation, Gemeric Unit). It is the first occurrence of this mineral in Slovakia. Mineralization is developed in a hydrothermal quartz-chlorite (± fine grained white mica) vein with abundant arsenopyrite and minor quantities of uraninite, gersdorffite, löllingite, galenobismutite, bismuthinite, maldonite, bismuth and gold. Maldonite forms irregular grains up to 12 μm in size embedded in arsenopyrite, or extremely fine capillary veinlets in it. An intergrowth of maldonite with bismuthinite was rarely also observed. The chemical composition of maldonite is relatively monotonous, its average empirical formula can be expressed as (Au1.79Fe0.15) Σ1.94 (Bi0.98As0.02S0.04) Σ1.04. Microstructural relationships of ore minerals suggest that maldonite precipitated in the final stages of ore mineralization, when the temperature of the system decreased (after the crystallization of sulphoarsenides and löllingite).
Unveiling the mineral resources and structural patterns in the Middle Benue Trough: a comprehensive exploration using airborne magnetic and radiometric data
(Taylor & Francis Group : Abingdon, 2024) Ekwok, Stephen Eguba; George, Anthony M.; Omori, Asuquo A.; Abdelrahman, Kamal; Ugar, Samuel Izama; Andráš, Peter; Morphy, Morod Iwong; Akpan, Anthony E.; Eldosouky, Ahmed Mohammed
The Middle Benue Trough (MBT) in Northcentral Nigeria is a geologically significant area with vast mineral resource potential. Employing airborne magnetic and radiometric data, this study utilized the Centre for Exploration Targeting on enhanced total magnetic intensity data to reveal geologic structures, lithological units and mineralization zones. Lineaments predominantly trended in NE-SW direction, with noteworthy orientations in NNE-SSW and E-W. Radiometric anomalies correlated with distinct lithological units, pinpointing granitic gneiss, alluvium, shale, siltstone and sandstone. A magnetically concentrated and potassium-rich area indicated potential polymetallic-magnetic mineralization. The 2D model illustrated igneous intrusions influencing prevalent geologic structures, such as sediment baking and doming. Thorough analysis, including source parameter imaging, standard Euler deconvolution and 2D forward modelling, revealed sediment thicknesses below 1500 m. This research enhances understanding of the MBT’s geological features, offering valuable insights for mineral exploration and resource assessment in the region.
Situation model of the transport, transport emissions and meteorological conditions
(Czech Technical University in Prague, 2024) Beneš, Viktor; Svítek, Miroslav; Michalíková, Alžbeta; Melicherčík, Miroslav
Air pollution in cities and the possibilities of reducing this pollution represent one of the most important factors that today’s society has to deal with. This paper focuses on a systemic approach to traffic emissions with their relation to meteorological conditions, analyzing the effect of weather on the quantity and dispersion of traffic emissions in a city. Using fuzzy inference systems (FIS) the model for predicting changes in emissions depending on various conditions is developed. The proposed model is based on traffic, meteorology and emission data measured in Prague, Czech Republic. The main objective of the work is to provide insight into how urban planners and policymakers can plan and manage urban transportation more efficiently with environmental protection in mind.
Biosférické rezervácie na Slovensku v začarovanom kruhu?
(Agentura ochrany přírody a krajiny ČR : Praha, 2024) Urban, Peter; Miňová, Lucia
Teaching aid for determining the dimensions of nuts and bolts using 3D printing
(Západočeská univerzita v Plzni, 2024) Kucmanová, Barbora; Kučerka, Martin
This paper explores the potential of 3D printing as a tool to make the teaching of engineering subjects more effective in the university. We address the question of how 3D printing can improve students' understanding of technical subjects in higher education. The aim of the work was to produce a concrete teaching aid as an educational tool to size bolts and nuts. We can conclude that 3D printing has great potential to improve the quality of education in technical subjects. It allows students to better understand theoretical concepts and acquire practical skills. In conclusion, 3D printing offers promising possibilities for making the teaching of technical subjects more effective.
Factor principal congruences and Boolean products in filtral varieties
(Springer Nature Switzerland AG : Basel, 2024) Davey, Brian A.; Haviar, Miroslav
Motivated by Haviar and Ploščica’s 2021 characterisation of Boolean products of simple De Morgan algebras, we investigate Boolean products of simple algebras in filtral varieties. We provide two main theorems. The first yields Werner’s Boolean-product representation of algebras in a discriminator variety as an immediate application. The second, which applies to algebras in which the top congruence is compact, yields a generalisation of the Haviar–Ploščica result to semisimple varieties of Ockham algebras. The property of having factor principal congruences is fundamental to both theorems. While major parts of our general theorems can be derived from results in the literature, we offer new, self-contained and essentially elementary proofs.
Interaktívna elektronická učebnica "Aktuálne problémy Európy" - jej východiská a možnosti využitia v stredoškolskej geografii
(Univerzita Konštantína Filozofa v Nitre, 2024) Škodová, Martina; Madleňák, Tibor; Gajdoš, Alfonz; Žoncová, Michaela
Slovakia, Europe, and the world are currently undergoing numerous changes, bringing various social, economic, and environmental challenges. Some of these changes have been occurring gradually over a long period, while others are rapid and have emerged only in recent years. The dynamics of these changes significantly affects whether they can be addressed within the geography curriculum and textbooks. We believe that school-level regional geography holds great potential for fostering a holistic understanding of complex phenomena and processes in the world and is a subject that should respond appropriately to current issues in Europe. However, based on an analysis of the geography curriculum, textbooks, and personal experience, we can conclude that such a response is currently taking place only to a very limited extent. There are several reasons for this, with one of the most critical being the rapid dynamics of these topics, which require continuous supplementation and updating of traditional educational materials. As part of the KEGA project, we developed an interactive textbook titled Current Issues of Europe. Its purpose is to complement the traditionally covered content of Europe’s regional geography with current topics and case studies. The textbook is primarily intended for high school students and their teachers. The goal of this paper is to present the textbook in terms of its creation, content, and potential applications.
New technologies and materials in 3D printing for modern design
(Západočeská univerzita v Plzni, 2024) Vojčeková, Terézia; Kučerka, Martin
This article explores the impact of modern technologies, particularly 3D printing, on architectural and industrial design. It analyses the shift from traditional production methods that emphasized the harmony between material and form to modern approaches that prioritize functionality and efficiency. It also focuses on new technologies in 3D printing, such as multi-material printing, metal printing and bioprinting, and their use in various design fields. The article highlights the advantages of 3D printing such as the ability to create complex shapes, speed of production and minimization of waste. It also presents specific examples of 3D printed products, including a chair made from recycled materials, furniture made from wood waste, and a 3D printed house. It concludes by highlighting the potential of 3D printing and new materials to revolutionize design and manufacturing.
Examples of safety and health risk factors in woodworking industry in Slovak Republic
(Technická univerzita vo Zvolene, 2024) Očkajová, Alena; Banski, Adrián; Kučerka, Martin; Vyhnáliková, Zuzana
In the article, we want to point out the still existing safety and health risks in woodworking operations, the essence of which lies in processing of non-homogeneous materials such as wood, with anisotropic properties and the occurrence of natural wood defects, manual feed of the workpiece into the cut, tools with a large number of cutting edges and high cutting speeds, manual handling of loads, but also in many cases in the irresponsible approach of the employees or employers themselve to the OHS. Failure to address or avoid these risks leads not only to injuries, but long-term work in this environment to occupational diseases, especially hearing loss, diseases of the musculoskeletal system, etc. Although the legislation covers all areas in terms of OSH, its implementation in practice is lengthy and not always adequate. The basis for characterizing the existing safety and health risks was the manual "Risk Assessment Basics - Good for You, Good for Your Company", Check list for Woodworking. Based on the description, it is obvious that the safety risks in woodworking are known, but in many operations they tolerate, and due to health risks, minimal attention is paid to manual handling of loads and ergonomics, the neglect of which contributes significantly to diseases of the musculoskeletal system.
Hydrothermal quartz-baryte veins containing Pb-Cu-Sb-(Bi) mineralization at Brusno-Brzáčka occurrence (Veporic Unit, Central Slovakia) and their supergene alteration
(Univerzita Komenského v Bratislave, 2024) Hoppanová, Eva; Ferenc, Štefan; Mikuš, Tomáš; Dolníček, Zdeněk; Kopáčik, Richard; Vlasáč, Jozef; Šimonová, Viera
The Brusno-Brzáčka occurrence (N 48.7698772°; E 19.4128150°) is located near the Brusno village (Slovenské Rudohorie Mts. Veporic Unit). Historically, the mineralization was explored by small-scale mining works located at the contact between the siliciclastic rocks of the Upper Permian and the Lower Triassic age. Paleo-Alpine metamorphic-hydrothermal mineralization is represented by quartz, baryte, or quartz-baryte veins, containing weak ore mineralization. Its succession is as follows: coarse-grained quartz I, pyrite (mineralization period I); baryte (II); tetrahedrite-(Zn), chalcopyrite (III); galena (IV) and quartz II (V). Supergene alteration produced initially covellite and spionkopite in the cementation zone. The oldest minerals in the oxidation zone are goethite, pyromorphite and mimetite. They were succeeded by the crystallization of Ba-rich anglesite, which partly overlaps in time with the precipitation of slightly younger anglesite. The formation of baryte partly overlaps with the deposition of anglesite, but in most cases, it is clearly younger. Bismutite is the youngest supergene mineral. A solid solution of anglesite–baryte with a Ba content from 0.29 apfu up to 0.51 apfu (i.e., Ba-rich anglesite) was identified at the studied site. This mineral phase covers the field of immiscibility of the natural solid solution PbSO4 – BaSO4, but the Ba/Pb ratio practically does not enter the baryte field (Pb-rich baryte).

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