1. Socio-demographic and health factors drive the epidemic progression and should guide vaccination strategies for best COVID-19 containmentRene Markovič, Marko Šterk, Marko Marhl, Matjaž Perc, Marko Gosak, 2021, izvirni znanstveni članek Opis: We propose and study an epidemiological model on a social network that takes into account heterogeneity of the population and different vaccination strategies. In particular, we study how the COVID-19 epidemics evolves and how it is contained by different vaccination scenarios by taking into account data showing that older people, as well as individuals with comorbidities and poor metabolic health, and people coming from economically depressed areas with lower quality of life in general, are more likely to develop severe COVID-19 symptoms, and quicker loss of immunity and are therefore more prone to reinfection. Our results reveal that the structure and the spatial arrangement of subpopulations are important epidemiological determinants. In a healthier society the disease spreads more rapidly but the consequences are less disastrous as in a society with more prevalent chronic comorbidities. If individuals with poor health are segregated within one community, the epidemic outcome is less favorable. Moreover, we show that, contrary to currently widely adopted vaccination policies, prioritizing elderly and other higher-risk groups is beneficial only if the supply of vaccine is high. If, however, the vaccination availability is limited, and if the demographic distribution across the social network is homogeneous, better epidemic outcomes are achieved if healthy people are vaccinated first. Only when higher-risk groups are segregated, like in elderly homes, their prioritization will lead to lower COVID-19 related deaths. Accordingly, young and healthy individuals should view vaccine uptake as not only protecting them, but perhaps even more so protecting the more vulnerable socio-demographic groups. Ključne besede: epidemic model, COVID-19, vaccination strategy, vaccination strategy, population heterogeneity, socio-demographic structure, metabolic disease, social network Objavljeno v DKUM: 14.11.2024; Ogledov: 0; Prenosov: 12
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2. Interplay between particle trapping and heterogeneity in anomalous diffusionHaroldo V. Ribeiro, Angel A. Tateishi, Ervin K. Lenzi, Richard L. Magin, Matjaž Perc, 2023, izvirni znanstveni članek Opis: Heterogeneous media diffusion is often described using position-dependent diffusion coefficients and estimated indirectly through mean squared displacement in experiments. This approach may overlook other mechanisms and their interaction with position-dependent diffusion, potentially leading to erroneous conclusions. Here, we introduce a hybrid diffusion model that merges a position-dependent diffusion coefficient with the trapping mechanism of the comb model. We derive exact solutions for position distributions and mean squared displacements, validated through simulations of Langevin equations. Our model shows that the trapping mechanism attenuates the impact of media heterogeneity. Superdiffusion occurs when the position-dependent coefficient increases superlinearly, while subdiffusion occurs for sublinear and inverse power-law relations. This nontrivial interplay between heterogeneity and state-independent mechanisms also leads to anomalous yet Brownian, and non-Brownian yet Gaussian regimes. These findings emphasize the need for cautious interpretations of experiments and highlight the limitations of relying solely on mean squared displacements or position distributions for diffusion characterization. Ključne besede: particle trapping, heterogeneity, diffusion, statistical physics Objavljeno v DKUM: 11.09.2024; Ogledov: 38; Prenosov: 4
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3. Exploring the inherent heterogeneity of vaccine hesitancy : a study of a childhood-vaccine-hesitant populationMonika Lamot, Andrej Kirbiš, Mitja Vrdelja, 2024, izvirni znanstveni članek Opis: Vaccine hesitancy and its determinants have been previously widely researched. Vaccine hesitancy has been defined as a continuum of attitudes, ranging from accepting vaccines with doubts to rejecting them. The present study aims to explore the heterogeneity of a childhood-vaccine-hesitant group by using a person-oriented approach-latent profile analysis. A non-representative cross-sectional sample of vaccine-hesitant Slovenians (N = 421, Mage = 35.21, 82.9% women) was used to identify differences based on their reliance on personal research (“self” researching instead of relying on science), overconfidence in knowledge, endorsement of conspiracy theories, complementary and alternative medicine, and trust in the healthcare system. The analysis revealed three profiles of vaccine-hesitant individuals. The most hesitant profile-vaccine rejecting-expressed the greatest reliance on personal research, expressed the highest endorsement of conspiracy theories and complementary and alternative medicine, showed moderate overconfidence in their knowledge, and expressed the highest levels of distrust in the healthcare system. We further found differences in sociodemographic structure and that the identified profiles differed in their attitudes regarding MMR, HPV, and Seasonal Influenza vaccinations. The present study demonstrates the heterogeneity of the vaccine-hesitant community and offers insights into some of the traits, which are crucial for designing pro-vaccine campaigns. Ključne besede: vaccine hesitancy, heterogeneity, latent profile analysis, complementary and alternative medicine, CAM, conspiracy theories, trust in healthcare system Objavljeno v DKUM: 21.08.2024; Ogledov: 101; Prenosov: 21
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4. eIDAS interoperability and cross-border compliance issuesMarko Hölbl, Boštjan Kežmah, Marko Kompara, 2023, izvirni znanstveni članek Opis: The eIDAS Regulation provides a common foundation for secure electronic interaction between citizens, businesses, and public authorities. We investigated and identified interoperability and cross-border compliance issues in this paper. We have identified the following weaknesses: Organizational independence, remote access to banking services, remote video identification, use of electronic signatures in public administration, commercial access to the eIDAS network, biometric authentication mechanisms, and, finally, some technical issues with the mechanisms used to provide security and authentication in eIDAS nodes. Ključne besede: eIDAS, interoperability, cross-border compliance, heterogeneity, European Union Objavljeno v DKUM: 12.02.2024; Ogledov: 315; Prenosov: 48
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5. Characterization of heterogeneous arc welds through miniature tensile testing and Vickers-hardness mappingStijn Hertelé, Jonas Bally, Nenad Gubeljak, Primož Štefane, Patricia Verleysen, Wim de Waele, 2016, izvirni znanstveni članek Opis: The heterogeneity of arc-welded connections is often ignored in structural assessments, giving rise to inaccuracies. Improved assessments taking into account heterogeneity require the characterization of local constitutive properties. We have compared two methods to do this: Vickers-hardness mapping and miniature tensile testing. Whereas the former is more straightforward to apply, the latter provides full-range stress-strain data. This paper discusses an experimental comparison of both methods on a heterogeneous arc weld. Miniature tensile tests were performed, using digital image correlation to measure the strain. The specimens were indented to compare their stress-strain response with Vickers hardness. Notwithstanding that small natural flaws invalidated some tests, reliable stress-strain curves were obtained. Vickers hardness testing is a convenient alternative if the yield and ultimate tensile strength are the only points of interest and the corresponding conversion inaccuracy is acceptable. Ključne besede: arc weld, heterogeneity, hardness, miniature tensile testing, digital image correlation Objavljeno v DKUM: 14.03.2017; Ogledov: 1364; Prenosov: 440
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6. Finite size effects in soft matter under an electric field stimulusSaša Harkai, 2016, magistrsko delo Opis: In this thesis, we study the effect of an external electric field on the properties of glass forming liquids. We present the properties relevant and important for understanding the phenomenon, such as the transition temperature and the temperature dependence of viscosity. We create a numerical model and use a method called molecular dynamics with the Lennard-Jones potential and an added external field as the interatomic potential to simulate molecular motion within a glass forming liquid. We implement analysis methods to calculate properties such as the radial distribution function, static structure factor, diffusion coefficient, non-Gaussian parameter, and relaxation time. We use the implemented methods to evaluate the molecular behaviour of the simulation and compare the results with theoretical predictions. Ključne besede: finite size, glass transition, diffusion constant, dynamic heterogeneity, electric field Objavljeno v DKUM: 21.09.2016; Ogledov: 1529; Prenosov: 121
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