Rene Markovič

• PhD
• asistent at University of Maribor

Understanding energy consumption patterns in the residential sector is of paramount importance for the design of new energy management strategies that are based on innovative information and communication technologies. Smart metering provides considerable opportunities in this respect and allows for the assessment of household characteristics, beha...

Words are the building blocks of human communication. They are arranged in sentences in a non-trivial and universal way, which implies the existence of fundamental organizational principles that have shaped language development. One of the fundamental examples is the Zipf’s law, which says that the frequency of word occurrence is roughly an inverse...

Quantitative analysis of the vascular network anatomy is critical for the understanding of the vasculature structure and function. In this study, we have combined microcomputed tomography (microCT) and computational analysis to provide quantitative three-dimensional geometrical and topological characterization of the normal kidney vasculature, and...

Collective beta cell activity in islets of Langerhans is critical for the supply of insulin within an organism. Even though individual beta cells are intrinsically heterogeneous, the presence of intercellular coupling mechanisms ensures coordinated activity and a well-regulated exocytosis of insulin. In order to get a detailed insight into the func...

Medvrstniško nasilje je kompleksen pojav, vpet v socialni kontekst, zato ga je treba proučevati z uporabo različnih pristopov in z vključevanjem različnih perspektiv. V znanstveni monografiji so predstavljeni ključni izsledki projekta, v katerem smo z uporabo raznovrstnih virov podatkov (samoporočanje, vrstniška imenovanja, poročanje učiteljev) in...

In recent years, a notable diversification in the geographical representation of the World’s top universities could be observed. Chinese universities play an increasingly prominent role in these rankings, thus indicating that we might be in the midst of a regional shift in academic performance. To explore this dynamics, we analyze seven years’ wort...

Youth’s social status (popularity and likability) relates with social status goals as well as bullying and prosocial behaviors within the context of classroom norms for bullying and prosocial behaviors, but less clear is how each of these factors interrelates with each other. The current study empirically analyses the concurrent relationships among...

The aim of our study was to explore students’ bystander roles in peer bullying considering the interaction between their individual and contextual characteristics. We included social status goals (popularity, social preference and social insecurity), moral disengagement and peer support as key variables for differentiating bystander behaviour. Our...

BACKGROUND The interrelation between COVID-19 and various cardiovascular and metabolic disorders has been a critical area of study. There is a growing need to understand how comorbidities like cardiovascular diseases and metabolic disorders affect the risk and severity of COVID-19. OBJECTIVE The objective of this study is to systematically analyze...

Background The interrelation between COVID-19 and various cardiovascular and metabolic disorders has been a critical area of study. There is a growing need to understand how comorbidities such as cardiovascular diseases (CVDs) and metabolic disorders affect the risk and severity of COVID-19. Objective The objective of this study is to systematical...

Introduction Type 2 diabetes mellitus (T2DM) is a complex, chronic disease affecting multiple organs with varying symptoms and comorbidities. Profiling patients helps identify those with unfavorable disease progression, allowing for tailored therapy and addressing special needs. This study aims to uncover different T2DM profiles based on medication...

The self-organization of open reaction systems is closely related to specific mechanisms that allow the export of internally generated entropy from systems to their environment. According to the second law of thermodynamics, systems with effective entropy export to the environment are better internally organized. Therefore, they are in thermodynami...

Islets of Langerhans are multicellular microorgans located in the pancreas that play a central role in whole-body energy homeostasis. Through secretion of insulin and other hormones they regulate postprandial storage and interprandial usage of energy-rich nutrients. In these clusters of hormone-secreting endocrine cells, intricate cell-cell communi...

Type 2 Diabetes Mellitus (T2DM) is a burdensome problem in modern society, and intensive research is focused on better understanding the underlying cellular mechanisms of hormone secretion for blood glucose regulation. T2DM is a bi-hormonal disease, and in addition to 100 years of increasing knowledge about the importance of insulin, the second hor...

Background: The pathogenesis of type 2 diabetes mellitus is complex and still unclear in some details. The main feature of diabetes mellitus is high serum glucose, and the question arises of whether there are other statistically observable dysregulations in laboratory measurements before the state of hyperglycemia becomes severe. In the present stu...

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 indivi...

Glucose metabolism plays a crucial role in modulating glucagon secretion in pancreatic alpha cells. However, the downstream effects of glucose metabolism and the activated signaling pathways influencing glucagon granule exocytosis are still obscure. We developed a computational alpha cell model, implementing metabolic pathways of glucose and free f...

Community lockdowns and travel restrictions are commonly employed to decelerate epidemic spreading.We here use a stochastic susceptible-infectious-recovered model on different social networks to determine when and to what degree such lockdowns are likely to be effective. Our research shows that community lockdowns are effective only if the links ou...

Beta cells within the pancreatic islets of Langerhans respond to stimulation with coherent oscillations of membrane potential and intracellular calcium concentration that presumably drive the pulsatile exocytosis of insulin. Their rhythmic activity is multimodal, resulting from networked feedback interactions of various oscillatory subsystems, such...

We investigate the relations between the enzyme kinetic flexibility, the rate of entropy production, and the Shannon information entropy in a steady-state enzyme reaction. All these quantities are maximized with respect to enzyme rate constants. We show that the steady-state, which is characterized by the most flexible enzymatic transitions between...

Type 2 diabetes mellitus is a complex multifactorial disease of epidemic proportions. It involves genetic and lifestyle factors that lead to dysregulations in hormone secretion and metabolic homeostasis. Accumulating evidence indicates that altered mitochondrial structure, function, and particularly bioenergetics of cells in different tissues have...

A precise structural organization of epithelial cells is needed for the proper functioning and development of different tissues. The epithelial cell packing mechanism is associated with mechanical interactions between cells that place the tissue in a state with the lowest free energy. In addition, planar cell polarity has been recognized as another...

Many tissues are gap-junction-coupled syncytia that support cell-to-cell communication via propagating calcium waves. This also holds true for pancreatic islets of Langerhans, where several thousand beta cells work in synchrony to ensure proper insulin secretion. Two emerging functional parameters of islet function are the location of wave initiato...

Background and aims Clinical evidence exists that patients with diabetes are at higher risk for Coronavirus disease 2019 (COVID-19). We investigated the physiological origins of this clinical observation linking diabetes with severity and adverse outcome of COVID-19. Methods Publication mining was applied to reveal common physiological contexts in...

We present a mathematical model of the energy-driven metabolic switch for glucagon and insulin secretion from pancreatic alpha and beta cells, respectively. The energy status related to hormone secretion is studied for various glucose concentrations. Additionally, the physiological response is studied with regards to the presence of other metabolit...

Type 2 diabetes mellitus (T2DM) has been associated with insulin resistance and the failure of β-cells to produce and secrete enough insulin as the disease progresses. However, clinical treatments based solely on insulin secretion and action have had limited success. The focus is therefore shifting towards α-cells, in particular to the dysregulated...

Self-organized critical dynamics is assumed to be an attractive mode of functioning for several real-life systems and entails an emergent activity in which the extent of observables follows a power-law distribution. The hallmarks of criticality have recently been observed in a plethora of biological systems, including beta cell populations within p...

We demonstrate that the maximum entropy production principle (MEPP) serves as a physical selection principle for the description of the most probable non-equilibrium steady states in simple enzymatic reactions. A theoretical approach is developed, which enables maximization of the density of entropy production with respect to the enzyme rate consta...

A coordinated functioning of beta cells within pancreatic islets is mediated by oscillatory membrane depolarization and subsequent changes in cytoplasmic calcium concentration. While gap junctions allow for intraislet information exchange, beta cells within islets form complex syncytia that are intrinsically nonlinear and highly heterogeneous. To s...

Simulated spatio-temporal activity under constant stimulation with homogeneous coupling. Typical computed [Ca2+]c responses of four different beta cells after switching to stimulatory conditions (upper panel, gray area indicates stimulatory conditions) and binarization of the computed oscillations of all cells (lower panel). The electrical coupling...

Representative animation of computed and binarized spatiotemporal [Ca2+]i activity under constant stimulation with glucose.

Movie of experimentally measured and binarized [Ca2+]i activity under constant stimulation with 8 mM glucose from the onset of glucose increase.

Movie of experimentally measured and binarized [Ca2+]i activity under periodic stimulation with 6-8-6-8-6-8-6 mM glucose.

The course of the simulated oscillatory stimulation protocol. Variations in the glucokinase reaction rate reflect the oscillatory changes in glucose.

Coupling in the multicellular beta cell model. (A) A typical structure of the intercellular network of beta cells. (B) The corresponding degree distribution. The beta cell network is quite homogeneous with a mean degree around 6. (C) The distribution of the electrical coupling coefficient. The coupling strength is rather heterogeneous and follows a...

Mathematical model and parameter values for beta cells.

Representative animation of computed and binarized spatiotemporal [Ca2+]i activity under periodic stimulation with glucose.

Network science is today established as a backbone for description of structure and function of various physical, chemical, biological, technological, and social systems. Here we review recent advances in the study of complex biological systems that were inspired and enabled by methods of network science. First, we present research highlights rangi...

Vasculature segmentation and reconstruction workflow. The flowchart shows the sequential order in which individual subroutines are arranged in our computational protocol in order to segment out the vascular structure and to reconstruct it. Used abbreviation are SO for the Strahler order, SOp for the parent vessel Strahler order, SOd for the daughte...

Global scale parameter analysis. (PDF)

In this work we investigated how modifications of the Ca2+ homeostasis in anterior lens epithelial cells (LECs) are associated with different types of cataract (cortical or nuclear) and how the progression of the cataract (mild or moderate) affects the Ca2+ signaling. We systematically analyzed different aspects of intra- and inter-cellular Ca2+ si...

Analysis of Ca2+ signals in individual LECs with respect to spontaneous activity. Comparison of: A normalized individual activation times, [Δtact,i]norm, and B deactivation times, [Δtdeact,i]norm, between spontaneously active and non-active cells. In the normalization process all values were divided by the average Δtact or Δtdeact in the given LC i...

Spatio-temporal organization of spontaneously active LECs in a characteristic LC. A Positions of LECs with marked spontaneously active cells (black rings, 29 of total 200 cells) in the LC. Positions of 6 spontaneously active LECs, for which traces are presented in the B panel (colored black rings). B Temporal traces of the normalized [Ca2+]i dynami...

Analysis of the activation speeds, SA, (A) and the deactivation speeds, SDA, (B) with regard to spontaneous activity. The one-way ANOVA test did not detect significant differences between the two groups of LCs, i.e. the group with spontaneously active LECs and the group without. The results indicate that the spontaneous activity does not have a sig...

Self-sustained oscillatory dynamics is a motion along a stable limit cycle in the phase space, and it arises in a wide variety of mechanical, electrical, and biological systems. Typically, oscillations are due to a balance between energy dissipation and generation. Their stability depends on the properties of the attractor, in particular, its dissi...

a r t i c l e i n f o a b s t r a c t Modern theory of networks has been recognized as a very successful methodological concept for the description and analysis of complex systems. However, some complex systems are more complex than others. For instance, several real-life systems are constituted by interdependent subsystems and their elements are s...

We study the functional connectivity patterns between beta cells in islets of Langerhans from mouse pancreas tissue slices. We build up the functional networks on the basis of correlations between calcium dynamics of individual cells, which were recorded by means of confocal laser-scanning calcium imaging. The extracted patterns of pairwise interac...

Epithelial tissues are structured and highly organized monolayers of cells with many different tissue-specific functions. Ordering of epithelium cells in living tissues relies on spatially and temporally regulated cell behavior and is of vital importance for their functioning. The underlying mechanisms that govern the development of the tissue arch...

The problem of making a network of dynamical systems synchronize onto a common evolution is the subject of much ongoing research in several scientific disciplines. It is nowadays a well-known fact that the synchronization processes are gradually influenced by the interaction topology between the dynamically interacting units. A complex coupling con...

Because of the complexity of processes that govern the regulatory mechanisms which control the cellular functions and dynamic behavior, mathematical models and numerical simulations are needed to fully grasp the mechanisms and functions of biological rhythms. In the last decade the theory of complex networks is frequently applied to address those i...

a b s t r a c t Synchronized neuronal activity has been observed at all levels of human and any other nervous systems and was suggested as particularly relevant in information processing and coding. In the present paper we investigate the synchronization of bursting neuronal activity. Motivated by the fact that in neural systems the interplay betwe...