1431. On a definition of logarithm of quaternionic functionsGraziano Gentili, Jasna Prezelj, Fabio Vlacci, 2023, izvirni znanstveni članek Povzetek: For a slice-regular quaternionic function $f$, the classical exponential function ${\mathrm exp} f$ is not slice-regular in general. An alternative definition of an exponential function, the $\ast$-exponential ${\mathrm exp}_\ast$, was given in the work by Altavilla and de Fabritiis (2019): if $f$ is a slice-regular function, then ${\mathrm exp}_\ast f$ is a slice-regular function as well. The study of a $\ast$-logarithm ${\mathrm log}_\ast f$ of a slice-regular function $f$ becomes of great interest for basic reasons, and is performed in this paper. The main result shows that the existence of such a ${\mathrm log}_\ast f$ depends only on the structure of the zero set of the vectorial part $f_v$ of the slice-regular function $f = f_0 + f_v$, besides the topology of its domain of definition. We also show that, locally, every slice-regular nonvanishing function has a $\ast$-logarithm and, at the end, we present an example of a nonvanishing slice-regular function on a ball which does not admit a $\ast$-logarithm on that ball. Ključne besede: regular functions over quaternions, quaternionic logarithm of slice-regular functions Objavljeno v DiRROS: 10.04.2024; Ogledov: 350; Prenosov: 150
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1432. Critical edges in Rips complexes and persistencePeter Goričan, Žiga Virk, 2023, izvirni znanstveni članek Povzetek: We consider persistent homology obtained by applying homology to the open Rips filtration of a compact metric space $(X, d)$. We show that each decrease in zero-dimensional persistence and each increase in one-dimensional persistence is induced by local minima of the distance function $d$ When $d$ attains local minimum at only finitely many pairs of points, we prove that each above mentioned change in persistence is induced by a specific critical edge in Rips complexes, which represents a local minimum of $d$. We use this fact to develop a theory (including interpretation) of critical edges of persistence. The obtained results include upper bounds for the rank of one-dimensional persistence and a corresponding reconstruction result. Of potential computational interest is a simple geometric criterion recognizing local minima of $d$ that induce a change in persistence. We conclude with a proof that each locally isolated minimum of $d$ can be detected through persistent homology with selective Rips complexes. The results of this paper offer the first interpretation of critical scales of persistent homology (obtained via Rips complexes) for general compact metric spaces. Ključne besede: persistent homology, Rips complex, critical simplex, reconstruction result Objavljeno v DiRROS: 10.04.2024; Ogledov: 442; Prenosov: 287
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1433. Does age matter? : The well-being of migrant children in comparative perspectiveZorana Medarić, Barbara Gornik, 2024, izvirni znanstveni članek Povzetek: This article explores the subjective perceptions of well-being of migrant children attending primary school (9-14 years) and secondary school (15-18 years) in Slovenia. It focuses on how they conceptualise their fears, worries and concerns, what is important for them to feel accepted and safe, and how they think about their past and the future. Using a comparative perspective, similarities and differences in the experience of well-being of these two age groups of migrants are explored. The analysis is based on open-ended narrative interviews with migrant children and revolves around the question of whether and how age influences their subjective perception of well-being. The article sheds light on age-specific meanings and understandings of migration processes based on the views and experiences of migrant children and youth regarding their well-being, bringing to the fore the perspectives of children that are often missing or underrepresented in integration policy. Ključne besede: acceptance, agency, well-being, age differences, migrant children Objavljeno v DiRROS: 09.04.2024; Ogledov: 408; Prenosov: 147
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1435. Researching the change in the weight of split oak firewood due to different drying methodsAmina Gačo, 2021, objavljeni znanstveni prispevek na konferenci Povzetek: In this paper, the influences of stacking methods and drying places of split oak firewood in winter conditions (Quercus cerris) have been experimentally and theoretically investigated, due to the great importance of use in heating with such wood. The research was conducted on a sample of 48 pieces of logs with bark made of freshly cut oak. The logs were obtained by mechanized technology with the help of grafting by a hydraulic splitter and a chainsaw. Each log was measured for a research length of 0.30 m, marked with numbers 1-24. On each log, the weight was measured on a scale of 5 kg with an accuracy of 0.5 grams. Drying of logs was performed in two places. The first drying place was in outdoor conditions, sheltered from the snow and ventilated. The second place was indoors, at approximately constant room temperature. The logs were stacked in a crossed way for better air circulation. They were dried between 15/12/2020 and 15/02/2021, a total of 62 days. The average initial weight of logs dried in the facility was 1130.3 g, in the dried state the average weight was 952.87 g, which represented 84.3% of the original weight. The average initial weight of logs dried in outdoor conditions was 1192.125 g, in the dried state 1076.37 g, which represented 90.29% of the original weight. The average initial water content in the logs dried in the facility was 37.9%, in the dried state it was 27.5%. For logs dried in outdoor conditions, the average initial amount of water was 36.6%, in the dried state the average amount of water was 31.2%. Ključne besede: weight, drying methods, splitting firewood, oak, stacking methods Objavljeno v DiRROS: 09.04.2024; Ogledov: 679; Prenosov: 498
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1436. Bio-based tannin-furanic-silk adhesives : applications in plywood and chemical cross-linking mechanismsEmanuele Cesprini, Johannes Jorda, Marco Paolantoni, Luca Valentini, Primož Šket, Valerio Causin, Diana E. Bedolla, Michela Zanetti, Gianluca Tondi, 2023, izvirni znanstveni članek Objavljeno v DiRROS: 09.04.2024; Ogledov: 368; Prenosov: 141
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1437. Effects of high-intensity interval training (HIIT) on physical performance in female team sports : a systematic reviewMima Stanković, Dusan Djordjevic, Nebojša Trajković, Zoran Milanović, 2023, pregledni znanstveni članek Povzetek: Abstract Background There is limited information regarding adaptation of HIIT in female athletes which is important since the adaptation to HIIT may be diferent compared to male athletes. Therefore, the aim of this systematic review was to summarize the efects of HIIT on physical performance in female team sports athletes. Methods The following databases Google Scholar, PubMed, Web of Science, Cochrane Library, ProQuest and Science Direct were searched prior to September 2nd, 2022. The inclusion criteria were longitudinal studies written in English, elite, sub-elite or college female team sports participants, and HIIT intensity had to be at 80–100% maximal heart rate. There were no exclusion criteria regarding the age of the participants or their training experience. The primary outcome measures were maximal oxygen uptake (VO2max), repeated sprint ability (RSA), change of direction speed, speed, explosive strength and body composition. Results A total of 13 studies met the inclusion criteria, with a total of 230 participants. HIIT improved VO2max in fve studies (ES from 0.19 to 1.08), while three studies showed improvement in their RSA (ES from 0.32 to 0.64). In addition, change of direction speed was improved in fve studies (ES from 0.34 to 0.88), while speed improved in four studies (ES from 0.12 to 0.88). Explosive strength results varied (ES from 0.39 to 1.05), while in terms of body composition, the results were inconsistent through observed team sports. Conclusion HIIT has signifcant efects on VO2max, RSA, change of direction speed, speed and explosive strength in female team sports, regardless of the competition level. Ključne besede: interval training, output, VO2max, physical fitness Objavljeno v DiRROS: 09.04.2024; Ogledov: 397; Prenosov: 262
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1438. Graphs with equal Grundy domination and independence numberGábor Bacsó, Boštjan Brešar, Kirsti Kuenzel, Douglas F. Rall, 2023, izvirni znanstveni članek Povzetek: The Grundy domination number, ${\gamma_{\rm gr}}(G)$, of a graph $G$ is the maximum length of a sequence $(v_1,v_2,\ldots, v_k)$ of vertices in $G$ such that for every $i\in \{2,\ldots, k\}$, the closed neighborhood $N[v_i]$ contains a vertex that does not belong to any closed neighborhood $N[v_j]$, where $jKljučne besede: Grundy domination, independence number, upper domination number, bipartite graphs Objavljeno v DiRROS: 09.04.2024; Ogledov: 302; Prenosov: 231
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1439. Mixed signals of environmental change and a trend towards ecological homogenization in ground vegetation across different forest typesJanez Kermavnar, Lado Kutnar, 2024, izvirni znanstveni članek Povzetek: Forest ground vegetation may serve as an early warning system for monitoring anthropogenic global-change impacts on temperate forests. Climate warming may induce a decline of cool-adapted species to the benefit of more thermophilous plants. Nitrogen deposition has been documented to potentially result in soil eutrophication or acidification, which can increase the proportion of species with higher nutrient requirements and species impoverishment caused by competitive exclusion. Abiotic forest disturbances are changing the light conditions in the forest understorey environment. In this resurvey study, we tested the magnitude and direction of change in alpha (species richness) and beta (within-site dissimilarity) diversity and composition of forest ground vegetation in forests of different types in Slovenia over fifteen years. Using plant-derived characteristics (Ellenberg-type indicator values) and by testing a priori predictions concerning expected effects of environmental drivers, we show that the magnitude and direction of forest ground vegetation diversity and floristic changes varies greatly between forest sites. Divergent responses at different sites resulted in low net change of alpha and beta diversity and a weak overall environmental signal. The largest decrease in species number was observed in lowland oak-hornbeam forests, which were also among the sites with the greatest compositional shifts. Changes in beta diversity did not show any consistent trend, and anticipated floristic convergence was not confirmed when all sites were considered. Thermophilization was mainly detected in montane beech sites and alpine spruce forests whereas eutrophication signal was most significant on nutrient-poor sites. Vegetation responses were strongly dependent on initial site conditions. Shrinkage of ecological gradients (process of ecological homogenization) suggests that sites positioned at the ends of the gradients are losing their original ecological character and are becoming more similar to mid-gradient sites that generally exhibit smaller changes. Our results point to the importance of local stand dynamics and overstorey disturbances in explaining the temporal trends in forest ground vegetation. Ground vegetation in Slovenian forests is changing in directions also dictated by multiple regional and global change drivers. Ključne besede: vegetation resurvey, thermophilization, eutrophication, forest disturbances, alpha and beta diversity, initial site conditions, ICP-Forests network Objavljeno v DiRROS: 09.04.2024; Ogledov: 476; Prenosov: 247
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1440. Wandering domains arising from Lavaurs maps with Siegel disksMatthieu Astorg, Luka Boc Thaler, Han Peters, 2023, izvirni znanstveni članek Povzetek: The first example of polynomial maps with wandering domains was constructed in 2016 by the first and last authors, together with Buff, Dujardin and Raissy. In this paper, we construct a second example with different dynamics, using a Lavaurs map with a Siegel disk instead of an attracting fixed point. We prove a general necessary and sufficient condition for the existence of a trapping domain for nonautonomous compositions of maps converging parabolically towards a Siegel-type limit map. Constructing a skew-product satisfying this condition requires precise estimates on the convergence to the Lavaurs map, which we obtain by a new approach. We also give a self-contained construction of parabolic curves, which are integral to this new method. Ključne besede: Fatou sets, holomorphic dynamics, parabolic implosion, polynomial mappings, skew-products, wandering Fatou components, parabolic curves, nonautonomous dynamics Objavljeno v DiRROS: 09.04.2024; Ogledov: 529; Prenosov: 149
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