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Corrosion of steel reinforcements in concrete constructions is a worldwide problem. To assess the degradation of rebars in reinforced concrete, an accurate description of electric current, potential and concentrations of various species present in the concrete matrix is necessary. Although the concrete matrix is a heterogeneous porous material with intricate microstructure, mass transport has been treated in a homogeneous material so far, modifying bulk transport coefficients by additional factors (porosity, constrictivity, tortuosity), which led to so-called effective coefficients (e.g., diffusivity). This study presents an approach where the real 3D microstructure of concrete is obtained from high-resolution X-ray computed tomography (XCT), processed to generate a mesh for finite element method (FEM) computations, and finally combined with a multi-species system of transport and electric potential equations. This methodology allows for a more realistic description of ion movements and reactions in the bulk concrete and on the rebar surface and, consequently, a better evaluation of anodic and cathodic currents, ultimately responsible for the loss of reinforcement mass and its location. The results of this study are compared with a state-of-the-art model and numerical calculations for 2D and 3D geometries.

The lifetime of a blast furnace (BF), and, consequently, the price of steel, strongly depends on the degradation of micropore carbon refractory materials used as lining materials in the BF hearth. One of the major degradation mechanisms in the BF hearth is related to the infiltration and dissolution of refractory materials in molten metal. To design new and more resilient materials, we need to know more about degradation mechanisms, which can be achieved using laboratory tests. In this work, we present a new investigation method of refractory materials infiltration resistance. The designed method combines a standard degradation test (hot metal penetration test) with X-ray computed tomography (XCT) measurements. Application of XCT measurements before and after molten metal infiltration allows observing changes in the micropore carbon refractory material’s microstructure and identifying the elements of the open pore structure that are crucial in molten metal infiltration.

A non-equilibrium diffusion–reaction model is proposed to describe chloride transport and binding in cementitious materials. A numerical solution for this non-linear transport with reaction problem is obtained using the finite element method. The effective chloride diffusion coefficients and parameters of the chloride binding are determined using the inverse method based on a diffusion–reaction model and experimentally measured chloride concentrations. The investigations are performed for two significantly different cements: ordinary Portland and blast furnace cements. The results are compared with the classical diffusion model and appropriate apparent diffusion coefficients. The role of chloride binding, with respect to the different binding isotherms applied, in the overall transport of chlorides is discussed, along with the applicability of the two models. The proposed work allows the determination of important parameters that influence the longevity of concrete structures. The developed methodology can be extended to include more ions, electrostatic interactions, and activity coefficients for even more accurate estimation of the longevity.

Crohn’s disease (CD) is a chronic inflammatory disease that most frequently affects part of the distal ileum, but it may affect any part of the gastrointestinal tract. CD may also be related to systemic inflammation and extraintestinal manifestations. Alzheimer’s disease (AD) is the most common neurodegenerative disease, gradually worsening behavioral and cognitive functions. Despite the meaningful progress, both diseases are still incurable and have a not fully explained, heterogeneous pathomechanism that includes immunological, microbiological, genetic, and environmental factors. Recently, emerging evidence indicates that chronic inflammatory condition corresponds to an increased risk of neurodegenerative diseases, and intestinal inflammation, including CD, increases the risk of AD. Even though it is now known that CD increases the risk of AD, the exact pathways connecting these two seemingly unrelated diseases remain still unclear. One of the key postulates is the gut-brain axis. There is increasing evidence that the gut microbiota with its proteins, DNA, and metabolites influence several processes related to the etiology of AD, including β-amyloid abnormality, Tau phosphorylation, and neuroinflammation. Considering the role of microbiota in both CD and AD pathology, in this review, we want to shed light on bacterial amyloids and their potential to influence cerebral amyloid aggregation and neuroinflammation and provide an overview of the current literature on amyloids as a potential linker between AD and CD.

Cancer diseases constitute a major health problem which leads to the death of millions of people annually. They are unique among other diseases because cancer cells can perfectly adapt to the environment that they create themselves. This environment is usually highly hostile and for normal cells it would be hugely difficult to survive, however neoplastic cells not only can survive but also manage to proliferate. One of the reasons is that they can alter immunological pathways which allow them to be flexible and change their phenotype to the one needed in specific conditions. The aim of this paper is to describe some of these immunological pathways that play significant roles in gynecologic neoplasms as well as review recent research in this field. It is of high importance to possess extensive knowledge about these processes, as greater understanding leads to creating more specialized therapies which may prove highly effective in the future.

Researchers are amazed at the multitude of biological effects of 3′,4′,5,7-tetrahydroxyflavone, more commonly known as luteolin, as it simultaneously has antioxidant and pro-oxidant, as well as antimicrobial, anti-inflammatory, and cancer-preventive, properties. The anticancer properties of luteolin constitute a mosaic of pathways due to which this flavonoid influences cancer cells. Not only is it able to induce apoptosis and inhibit cancer cell proliferation, but it also suppresses angiogenesis and metastasis. Moreover, luteolin succeeds in cancer cell sensitization to therapeutically induced cytotoxicity. Nevertheless, apart from its promising role in chemoprevention, luteolin exhibits numerous potential utilizations in patients with conditions other than neoplasms, which include inflammatory skin diseases, diabetes mellitus, and COVID-19. This review aims to present the multidimensionality of the luteolin’s impact on both neoplastic and nonneoplastic diseases. When it comes to neoplasms, we intend to describe the complexity of the molecular mechanisms that underlay luteolin’s anticancer effectiveness, as well as to prove the usefulness of integrating this flavonoid in cancer therapy via the analysis of recent research on breast, colon, and lung cancer. Regarding nonneoplastic diseases, this review aims to emphasize the importance of researching the potential of luteolin in areas such as diabetology, virology, and dermatology as it summarizes the most important discoveries in those fields regarding its application.

The development of the high-tech sector has so far been studied within the cities, leaving their functioning within the special economic zones in the context of metropolitan belonging unexplored. The main purpose of the article is to determine whether the economic zone has a positive impact on the economic development of cities, which in the context of this research, has been operationalized with the use of computer-aided systems. The authors purposefully choose a Metropolis GZM, Poland (GZM), and Katowice Special Economic Zone (KSEZ). The importance of the high-tech sector in the GZM depends on the development of business in the region. Innovative specializations of cities located in the KSEZ were examined from the point of view of their perception by users of these new technologies, i.e., city residents. The research was conducted among over 1000 inhabitants of 16 cities in the GZM Metropolis. The results show correlations between the existence of modern businesses in metropolitan cities and their development of useful technologies, perceived from the perspective of residents.

Naringenin is a trihydroxyflavanone present in large amount in different citrus fruits, e.g., oranges, pomelos, grapefruits, but also in tomatoes, fenugreek and coffee. It has a wide range of pharmacological and biological effects beneficial to human health. Its antioxidant, anti-cancer, anti-inflammatory, antifungal and antimicrobial activity is frequently reported in scientific literature. In this review we presented the current state of knowledge on the antimicrobial activity of naringenin and its natural and synthetic derivatives as a phytobiotic against resistant Gram-positive and Gram-negative bacteria as well as fungi in humans. Most of the data reported here have been obtained from in vitro or in vivo studies. Over the past few years, due to the overuse of antibiotics, the occurrence of bacteria resistant to all available antibiotics has been growing. Therefore, the main focus here is on antibiotic resistant strains, which are a significant, worldwide problem in the treatment of infectious diseases. The situation is so alarming that the WHO has listed microbial resistance to drugs on the list of the 10 most important health problems facing humanity. In addition, based on scientific reports from recent years, we described the potential molecular mechanism of action of these bioflavonoids against pathogenic strains of microorganisms. As plant-derived substances have been pushed out of use with the beginning of the antibiotic era, we hope that this review will contribute to their return as alternative methods of preventing and treating infections in the epoch of drug resistance.

Sustainable City solutions can become an essential element of the development of contemporary urban communities. This development path can also provide opportunities for organisations operating in cities and metropolises. An inherent feature of the organisation which a city constitutes is that it enables the people who make it up to cooperate. Climate packages, including the Green Deal and Fit for 55, are implemented in Europe, while in Poland decarbonisation processes are underway. The main challenges in this area include, on the one hand, a search for savings of energy consumed, and, on the other hand, a reduction in pollution resulting from the use of transport or heat or energy sources. Cities and metropolises will become green only when they manage to cope with these problems. The article aims at showing various facets of sustainable smart city management. With relations, information and knowledge gaining importance as the key organisational resource, cities have become, as organisations, an essential element of contemporary societies and organisations. In recent times, the harmful emissions from heating installations have drawn the attention of the public opinion in Poland. Polish municipalities distribute heat which mostly comes from local, most often district heating systems where energy is generated on a wide scale from coal combustion. This study compares the results of an air quality survey and those of a case study to assess the potential for the implementation of an automated heat control system in cities. On the basis of solutions implemented in the Warsaw Metropolis, the possibility of their implementation in the Upper Silesian (GZM) and Poznań Metropolises, too, was also assessed. Throughout Poland, there is a large potential for the application of innovative smart technologies in district heating systems to reduce the levels of harmful emissions. These reductions, which are still possible, could translate into a significant improvement in the attractiveness and competitiveness of municipalities. Finally, practical recommendations are being provided.

The article uses the case study of a polycentric metropolitan area as a starting point for a debate about the available tools for managing the network aspects of intelligent cities. We show that the construction of talents, the development of knowledge among officials and inhabitants, and technological tools such as Hubgrade (which allows for heat delivery process control, supervision, inspection, and results in emission reduction) are prerequisites for the sustainable development of cities. It is critical to understand that technological solutions are insufficient to accomplish such a task. Relevant stakeholders need to consciously take advantage of technological tools and build and utilise 4T potential and the self-learning capabilities of the organisations. An inherent feature of an organisation, such as a city, is cooperation between the people who build it. The main challenges of cities includes the reduction of pollutants resulting from the use of transport, heat sources, or energy production. In many cities, an efficient manner of reducing carbon dioxide emissions is to limit the consumption of thermal energy. In order to simultaneously maintain thermal comfort, in this situation, it is necessary to use intelligent technologies. The paper includes research related to the knowledge and development of 4T potentials (technology, trust, talent, tolerance) and to networking expansion by introducing the automated Hubgrade system, used in Warsaw district heating, into a similar metropolitan area. Along with an increase in the significance of relations, information, and knowledge as a key organisational resource, cities, as organisations, have become an important element of contemporary communities and organisations. They have the possibility of a positive climate change. The possibility of cooperation and networking between people forming an organisation is its inherent feature, such as in the Hubgrade project. Conclusions and recommendations are drawn for the analysed case—linking 4T potentials and the Hubgrade system—with the potential for future generalisations and extrapolations. The authors performed a simulation of possible energy savings and the reduction of harmful emissions in Metropolis GZM.

Harmful emissions from heating installations have recently received public attention in Poland. Polish municipalities mainly take their heat from local district heating networks with large-scale coal-fired heat sources. Today, transition to nonemissive sources on this scale would be impractical. The easiest way to reduce carbon emissions is to limit heat consumption, but at the same time, to preserve thermal comfort, the application of smart technologies is necessary. Veolia operates on 71 district heating systems in Poland, including Warsaw, Lodz, and Poznan. Since heat consumption in Warsaw and Metropolis GZM is at a similar level, this is a case study of Hubgrade automation system application within the Warsaw district heating network. This paper also presents results of simulation of harmful emission reduction potential in Metropolis GZM. Simulation results show that there is a potential for saving approximately 275 kt of CO2 for the whole Metropolis GZM.

Fleet electrification is one of the measures proposed for achieving climate neutrality in the coming years. The replacement of internal combustion engine vehicles with electric vehicles has a positive impact on carbon emission reduction in some countries. However, in countries highly dependent on fossil fuels, such a possibility requires examination with respect to the means of electricity generation and fuel mix used in their power systems. One such country is Poland, selected as an example of an economy strongly dependent on fossil fuels. The main objective of this paper is to investigate the impact of fleet electrification of an individual company located in Poland on the reduction of carbon emissions. The concept and calculations are based on historical data on the single-year mileage and fuel consumption of 619 cars used by this company. Even though the Polish power system is based on fossil fuels, fleet electrification could contribute to a reduction in carbon emissions of 24%. The decrease in operational costs by EUR 370 thousand/year is also significant. Apart from environmental and economic impacts, this paper provides valuable findings on the difference between catalogue and real-driving data application in the various analyses. With respect to Polish fuel mix in 2019, the application of data published by car producers shows that fleet electrification would increase carbon emissions by 14% in this company. This means that depending on the initial assumptions, different conclusions can be drawn by policymakers, regulatory bodies, academics, or other groups of interest.