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  Aerodynamic Loading of Lightweight Green Roof Systems on Industrial Buildings: A Case-Based CFD Study of an Existing Industrial Hall

  (Elsevier, 2026-02-21) Kučírek, Pavel; Šikula, Ondřej; Krajčík, Michal; Mohapl, Martin; Arici, Muslum

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  Large low-rise industrial halls offer extensive roof areas for adding vegetated roof assemblies (VRAs) as part of reconstruction. However, existing structures often require lightweight VRAs to avoid overloading. To assess the wind resistance of such lightweight systems, atmospheric boundary layer simulations were conducted in OpenFOAM using Reynolds-Averaged Navier-Stokes approach for a cuboid industrial hall in a low-density built environment, representative of many industrial facilities worldwide. Additional roof geometries and adjoining-building cases were analysed to cover configurations not addressed in prior studies. Compared with a simple cuboid, a combined cuboid-bevel geometry experienced notably higher roof underpressure. The presence of an adjoining building further intensified corner-zone suction, increasing peak local suction from 608 Pa to 830 Pa (37%). For an extreme air velocity of 43.1 m/s recorded at the Brno (Czech Republic) meteorological station, the computed pressures were compared with the European standard for wind actions on structures. The peak suction reached approximately 4 kPa at the roof corner for a 45° wind direction, about twice the allowable limit for components with effective area 1 m2, indicating that perpendicular-wind (0°) analyses may underestimate the risk for modular systems. The results have implications for the long-term green-roof performance, because wind-induced uplift or substrate displacement can alter VRA thermal behaviour; maintaining aerodynamic stability is therefore essential to sustain the intended thermal performance. The findings highlight potential failure mechanisms, particularly in unanchored lightweight VRAs, and support more resilient green-roof design and standards for industrial buildings.

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  An Integrated Approach to Optimizing the Energy Efficiency of Water Supply—The Way to Achieve Effective Management

  (Multidisciplinary Digital Publishing Institute (MDPI), 2024-12-24) Mečíř, Filip; Kučera, Tomáš; Snášel, Daniel; Hluštík, Petr

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  Escalating energy costs in recent years have spurred an examination of energy cost reduction strategies. Among these, exploring spot markets and building photovoltaic power plants at water facilities have emerged as promising options. This study focuses on the utilization of genetic algorithms to optimize pumping operations. Through simulations and case studies on small and medium-sized water distribution networks in the Czech Republic, the effectiveness of genetic algorithms at reducing operational costs is demonstrated. The integration of neural networks for predictive modeling and real-time decision-making complements the genetic algorithm approach, promising significant operational savings amid evolving energy market dynamics.

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  Word equations in synergy with regular constraints (extended version)

  (Springer Nature, 2025-05-21) Blahoudek, František; Chen, Yu-Fang; Chocholatý, David; Havlena, Vojtěch; Holík, Lukáš; Lengál, Ondřej; Síč, Juraj

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  We propose a new automata-based algorithm for solving string constraints that tightly integrates reasoning about equations and regular constraints. Exchanging information between the two allows an efficient pruning of generated combinatorial cases. The algorithm is based on a  novel language-based characterization of satisfiability of word equations with regular constraints. Namely, satisfiability of an equation is implied by its stability: the concatenation of the regular languages constraining variables on the left-hand side equals the concatenation of the languages on the right-hand side. It is complete for the chain-free string constraints. We experimentally show that our prototype implementation is competitive with the best string solvers and even superior on difficult examples.

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  Study on the Binding of Five Plant-Derived Secondary Metabolites to G-Quadruplexes

  (American Chemical Society, 2026-01-20) Vrtalová, Lucie; Dobrovolná, Michaela; Platero-Rochart, Daniel; Ptaszek, Aleksandra L.; Brázda, Václav; Sánchez-Murcia, Pedro A.

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  Chemical targeting of noncanonical secondary structures of DNA and RNA has emerged as a promising approach for therapeutic development. The most promising targets seem to be four-stranded structures in the G-rich regions of the genome, known as G-quadruplexes (G4s), which are associated with important regulatory regions including promoters. In this study, we tested and modeled the binding of five plant-derived secondary metabolites, known for their antiproliferative activity in vitro, to two G4s found in the human genome: the first at the c-Myc proto-oncogene and the second at the human telomere repeat region. Among the tested compounds, brucine exhibited the strongest interaction with both G4 sequences, while ellagic acid demonstrated binding efficacy comparable to that of brucine in the c-Myc sequence. Through molecular dynamics simulations and the Markov state model, we explored the binding modes of these ligands, elucidated the G4 stability in the bound state, and investigated the fluorescence quenching effect of thioflavin T (ThT) upon its displacement. The biological effects of these natural compounds were investigated in human cell lines, and the interaction with G4s was verified experimentally using a fluorescence displacement assay and CD spectroscopy. This study demonstrates the interaction of these natural compounds with the G4 structures and their implications for therapeutic targeting.

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  Effect of cement paste and saline solution composition on chemical and physical binding of chlorides

  (Springer Nature, 2024-12-14) Kuzielova, Eva; Compeľová, Kristina; Peciar, Peter; Buňová, Lenka; Kureková, Valéria; Másilko, Jiří

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  Chloride ingress, along with chemical and physical binding in cement pastes, was studied in relation to the paste composition, saline solution, and hydration regime used. Unblended cement paste and pastes prepared with combinations of SF with MK and SF with BFS, replacing 30% of the cement mass, were exposed to NaCl and geothermal solutions for 7 days, either directly or following 7 days of water curing. The surface and middle parts of the samples were evaluated using TGA, XRD, FTIR, ion chromatography (Cl concentration), and ICP-OES (Na concentration). In addition, compressive strength (CS) measurements were performed. In MK-containing samples, Cl-AFm (hydrocalumite) formed mainly through an ion exchange mechanism, while in BFS-containing samples and the reference pastes, Cl-AFm phases primarily formed through the reaction of Cl with C3A and Ca(OH)2 and increased physical adsorption of Cl onto C-(A-)S-H were determined. Exposure to NaCl solution led to more chlorides being chemically incorporated into Cl-AFm, as well as higher levels of physically adsorbed and free chlorides in the pore solutions, compared to the geothermal solution. Pozzolanic reactions of additives, the acceleration of hydration induced by the solutions, especially by the geothermal one, and the densification of the matrix by the products of chloride reactions in blended samples resulted in CSs comparable to or higher than those reached after standard water curing. CSs of referential samples decreased following the decalcification of the initially formed C-(A-)S-H phases.

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