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In light of the forthcoming second generation Eurocodes (EC), the results of conducted systematic in-plane cyclic and compressive tests on three-leaf stone masonry walls are discussed following new requirements and provisions. The new proposal for EC8-3 for existing buildings is based on partial factors safety approach, though it considers different uncertainties in defining input parameters for effective seismic performance-based assessment. Prior to its application, massive calibration effort will be needed since there is no standardized method for shear testing of masonry walls. In this paper, the performance limit states damage, resistance, and displacement capacities from conducted test results were evaluated and assessed through comparison with analytical solutions and imposed limit values, as stated in existing codes. The test results provide a much higher deformation capacity than the limits provided in both existing and new proposal of EC8-3 as well as those in the ASCE code provisions. The reason for this lies in the soft, "ductile" mortar for which the presumed resistance according to code provisions should be significantly higher when considering good quality ashlar three-leaf stone masonry.

Human activity is becoming the dominant influence in shaping the face of the earth. In 2020 we reached the crossover point where the anthropogenic mass reached approximately 1.1 teratonnes which is equal to all living biomass on Earth. The mass of plastic generated so far is nearly double the mass of all marine and terrestrial animals combined. Plastics enter the environment through plastic litter which gradually degrades into microplastics (MP). But there is little information about the lifespan of these materials and their degradation rates in the environment. For this reason, the degradation of plastic litter remains a fundamental question for MP research. In the present study forty-four, naturally degraded lobster trap tags made of polyethylene (PE) were collected from the marine environment and several naturally aged polypropylene (PP) items were studied in respect of their degradation in the environment. The manufacturing dates printed on lobster tags were used as a temporary indication of being present in the environment as plastic litter. The oldest PE tag was manufactured in 1983 whereas some PP items were more than forty years old. The results revealed an extreme degradation of several PP items that has a very pronounced effect on fragmentation. The thickness of the items allowed us to assess the state of the material that was not exposed to environmental influences. The PE tags do not show a direct degradation correlation with their time of manufacturing. The oldest PE tag made in 1983 seems to be robust whereas a lobster tag manufactured in 2007 shows the highest degradation as confirmed by ATR-FTIR. One interesting pattern observed was the red-colored lobster tags were showing more degradation while blue-colored tags were showing the least degradation. There seems to be an effect of item coloring suggesting an important role of additives in the degradation. Also see: https://micro2022.sciencesconf.org/426782/document, In MICRO 2022, Online Atlas Edition: Plastic Pollution from MACRO to nano

There is a lack of knowledge regarding the parameters needed for the effective seismic performance assessment of historical stone masonry buildings. The paper presents the results of an extensive experimental campaign consisting of four compression and fifteen in-plane cyclic shear tests on three-leaf ashlar stone masonry walls and its constituents. The morphology, level of vertical load, and testing boundary conditions were systematically varied, and their influence on the load-bearing and deformation capacities, stiffness, ductility and energy dissipation was analysed. Good consolidation of the inner core enables in-plane failure mechanism of the walls to occur without decisive out-of-plane damage. The boundary conditions applied significantly influence the failure modes and large deformation capacities obtained, whereas transverse connections in the case of a shear failure mechanism do not significantly influence the overall lateral in-plane response of walls.

Urolitini so metaboliti elagitaninov, kateri nastanejo s pomočjo črevesnih bakterij. Veliko pozornosti so pritegnili zaradi potencialnih antioksidativnih, protivnetnih, protirakavih učinkov in delovanja proti nevrodegenerativnim boleznim. Poteka še veliko raziskav o samih spojinah in njihovih zdravilnih učinkih. Pomemben je tudi razvoj metod, s katerimi se lahko urolitine določa v različnih bioloških vzorcih. V tej nalogi sem se osredotočila na kvalitativno in kvantitativno določitev urolitina A v vzorcih prašičjega blata. Tovrstni vzorci so najlažje dostopni in lahko povedo veliko o metabolizmu. Razvita je bila metoda za pripravo vzorca in analizo na sistemu revezno fazne tekočinske kromatografije visoke ločljivosti z UV-Vis detekcijo. Preizkušenih je bilo več načinov in topil za ekstrakcijo vzorca. Razvita je bila ekstrakcija tekoče-tekoče z raztopino vzorca in etil acetatom, s katero se vzorec skoncentrira, vendar je pri postopku veliko izgub. Za najbolj optimalno se je izkazala enofazna ekstrakcija z mešanico topil metanola in vode v razmerju 80:20 z dodatkom kisline. Vzorci blata so kompleksni in opažena je bila velika raznolikost v vsebnosti motečih komponent, ki so v nekaterih primerih vplivali na določevanje urolitina A v vzorcu. Najboljša ločba je bila dosežena s stacionarno fazo z vezanimi fenil-heksil skupinami in gradientnim profilom mobilnih faz 0,1 % raztopine H3PO4 v vodi ter acetonitrila. Uporabljena optimalna valovna dolžina je bila 240 nm. Določena je bila linearnost, ponovljivost metode, LOD, LOQ in vpliv matrice. Metoda je primerna za kvalitativno določevanje, kvantitativno določevanje pa je v določenih primerih moteno zaradi prisotnost motečih komponent. Preizkušena je bila topnost urolitina A v topilih metanol, mešanici metanola in vode v razmerju 80:20, vodi in etil acetatu. Najbolj topen je v metanolu s topnostjo 0,737 g/L in najslabše v vodi s topnostjo 0,170 g/L. Preverjena je bila stabilnost urolitina A v topilih DMSO, metanolu in mešanici metanola in vode v razmerju 80:20 pri koncentracijah osnovne in delovne raztopine ter pri različnih pogojih: v zamrzovalniku pri -20 °C, v hladilniku pri 4 °C, v temi pri sobni temperaturi in na svetlobi pri sobni temperaturi. Stabilnost je upadala le v primeru raztopine, ki je bila izpostavljena svetlobi v topilu DMSO. Urolithins are metabolites of ellagitannins produced by intestinal bacteria. They have attracted a lot of attention due to their potential antioxidant, anti-inflammatory, anti-cancer effects and their action against neurodegenerative diseases. There is still a lot of research going on about the compounds themselves and their health effects. The development of a method by which urolithin can be determined in various biological samples is also important. In this master thesis, I focused on the qualitative and quantitative determination of urolithin A in pig feces samples. These types of samples are the most easily accessible and can tell a lot about the metabolome. A method for sample preparation and analysis on a reverse-phase high-performance liquid chromatography system with UV-Vis detection was developed. Several methods and solvents to extract the sample were tested. A liquid-liquid extraction with a solution of the sample and ethyl acetate has been developed to concentrate the sample, but there are many losses in the process. Single-phase extraction with a solvent mixture of methanol and water in a ratio of 80:20 with the addition of acid proved to be the optimal. Stool samples are so complex and a great diversity in the content of disturbing components was observed, which in some cases affected the determination of urolithin A in the sample. The best separation was achieved with a stationary phase with attached phenyl-hexyl groups and a mobile phase gradient profile of 0.1 % solution of H3PO4 in water and acetonitrile. The optimal wavelength used was 240 nm. Linearity, method reproducibility, LOD, LOQ and matrix effect were determined. The method is suitable for qualitative determination, but quantitative determination is disturbed in certain cases due to the presence of interfering components. The solubility of urolithin A was tested in the solvent methanol, an 80:20 mixture of methanol and water, water and ethyl acetate. It is best soluble in methanol with a solubility of 0.737 g/L and the worst in water with a solubility of 0.170 g/L. The stability of urolithin A was checked in the solvents DMSO, methanol and a mixture of methanol and water in a ratio of 80:20 at the concentrations of the stock and working solution and under different conditions: in a freezer at -20 °C, in a refrigerator at 4 °C, in the dark at room temperature and in the light at room temperature. The stability dropped only in the case of the solution exposed to light in the DMSO solvent.

Poslovanje javnih institucij se z razvojem družbe in tehnologije spreminja ter prilagaja njenim potrebam in posamezniku. V izrednih razmerah, kot je bil covid-19, pa je potrebno prilagajanje in iskanje alternativnih rešitev pospešiti. V delu smo zato preučevali, kako so se izbrane slovenske občine odzvale na izzive epidemije covida-19. Želeli smo ugotoviti, v kolikšni meri so izkoristile pomoč informacijske tehnologije pri spremenjenem načinu dela. Analizirali smo spremembe poslovanja izbranih občin in zaznali izzive in pomanjkljivosti e-poslovanja. Podrobnejšo raziskavo smo naredili s pomočjo spletne ankete. Z analitično metodo in metodo komparacije smo prišli do ključnih ugotovitev oz. odgovorov na vprašanje, kaj so bile glavne težave in izzivi v času epidemije na Občini Bistrica ob Sotli, Občini Brežice in Mestni občini Krško. V okviru raziskave smo ugotovili, da sta zaposlenim največji izziv predstavljala namestitev in uskladitev novih aplikacij ter čas za uporabo le-teh in komunikacija s strankami. Težave obsežnejšega e-poslovanja so bile: dostop in neprilagojenost informacijskega sistema za delo na daljavo, dostop do službenih dokumentov, pomanjkanje elektronskega podpisa, prenos velikih datotek in čas za prilagoditev. Ovire so predstavljale tudi pomanjkljive digitalne spretnosti in veščine zaposlenih. Pri delu v prihodnosti bo e-poslovanje zagotovo obsežnejše. Več bo dela na daljavo, stremljenja k nadaljnji racionalizaciji in poenostavitvi dela ter konstantni rabi informacijsko-komunikacijske tehnologije. Zaposlenim je smiselno omogočiti digitalno podpisovanje, posodobiti informacijske sisteme, prenesti dokumentacijo v elektronsko obliko, poenotiti oddajo e-vlog s portalom eUprava in spodbujati občane k uporabi e-storitev. Tako izbranim občinam kot drugim podobnim institucijam bodo rezultati dela omogočili pravilnejše korake h kvalitetnejšemu e-poslovanju z maksimalno izkoriščenostjo prednosti, ki jih zagotavlja IKT. The business of public institutions changes and adjusts to the demands and development of society and individuals. In emergency situations, such as covid-19, it is necessary to adapt and find alternative solutions quickly. In this assignment, we analysed how selected Slovenian municipalities responded to the challenges of the covid-19 epidemic. We wanted to establish to what extent they have used the assistance of information technology in the changed working methods. We analysed changes in the business of selected municipalities and identified the challenges and shortcomings of e-business. Using an online survey questionnaire, we conducted more detailed research. Using the analytical method and the method of comparison, we came to the main findings about the significant problems and challenges during the epidemic in the Municipality of Bistrica by Sotla, the Municipality of Brežice and the Municipality of Krško. As part of the research, we found out that the biggest challenge for employees was the installation and coordination of new applications and the time used for communication with the applicants. The problems of more extensive e-business were access and inadequacy of the information system for remote work, access to official documents, lack of electronic signature, the transfer of large files and time for adjustment. Lack of digital skills and skills staffing levels were also obstacles. In the future, e-business will undoubtedly be more extensive. There will be more remote work, a focus on further rationalization and simplification of work, and constant use of information and communication technology. Therefore, employees should be provided with digital signatures, information systems updates, documentation transfer in e-data, unification of e-applications submissions with the eGovernment portal and encouragement of citizens to use e-services. The results of the assignment will enable both the selected municipalities and other similar institutions to take more correct steps towards higher quality e-business, with maximum utilization of the advantages brought by ICT.

Due to their comparable fire characteristics and surface preparation, light-frame timber panels using cement-particle boards (CPB) as a sheathing material present a potential alternative to gypsum-fibre boards. An experimental campaign was conducted to evaluate the behaviour of CPB light-frame-timber panels under in-plane lateral loading. Monotonic and cyclic in-plane shear tests were conducted on full-size panels, following preceding tests on the stapled sheathing-to-timber connections used in the panels. The influence of the boards’ thickness and staple geometry on the response of connections and panels was studied, also on panels with an asymmetrical CPB layout, which proved not to have a negative influence on the panels’ lateral load-bearing capacity. Furthermore, in order to improve the seismic response, panels, which had almost twice the number of staples compared to the basic panel, were tested; one variation with two rows of staples, and the other with the staples spaced closer together, such that the spacing distance was halved. The tests revealed a significant, though not proportional, increase in lateral resistance in the strengthened panels. Fastening the CPB with two rows of staples proved the better option, since subsequent failure of the CPB along the connections, as opposed to ductile failure of the staples in the basic panels, proved not to reduce the panels’ deformation capacity. The paper also compares the test results of the connections and panels to analytical results according to Eurocode 5 (EC5), the European code provision for the design of timber structures. Nasl. z nasl. zaslona. Opis vira z dne 5. 1. 2022. Št. članka: 113757. Abstract. Bibliografija: str. 14.

We used a combination of density functional theory (DFT) calculations and the implicit quantization of the acidic N-H and O-H bonds to assess the effect of deuteration on the binding of agonists (2-methylhistamine and 4-methylhistamine) and antagonists (cimetidine and famotidine) to the histamine H2 receptor. The results show that deuteration significantly increases the affinity for 4-methylhistamine and reduces it for 2-methylhistamine, while leaving it unchanged for both antagonists, which is found in excellent agreement with experiments. The revealed trends are interpreted in the light of the altered strength of the hydrogen bonding upon deuteration, known as the Ubbelohde effect, which affects ligand interactions with both active sites residues and solvent molecules preceding the binding, thus providing strong evidence for the relevance of hydrogen bonding for this process. In addition, computations further underline an important role of the Tyr250 residue for the binding. The obtained insight is relevant for the therapy in the context of (per)deuterated drugs that are expected to enter therapeutic practice in the near future, while this approach may contribute towards understanding receptor activation and its discrimination between agonists and antagonists.

Wastewater treatment plants, the last barrier between ever-increasing human activities and the environment, produce huge amounts, of unwanted semi-solid by-product - waste activated sludge. Anaerobic digestioncan be used to reduce the amount of sludge. However, the process needs extensive modernisation and refinement to realize its full potential. This can be achieved by using efficient pre-treatment processes that result in high sludge disintegration and solubilization. To this end, we investigated the efficiency of a novel pinned disc rotational generator of hydrodynamic cavitation. The results of physical and chemical evaluation showed a reduction in mean particle size up to 88%, an increase in specific surface area up to 300% and an increase in soluble COD, NH4-N, NO3-N, PO4-P up to 155.8, 126.3, 250 and 29.7%, respectively. Microscopic images confirmed flocs disruption and damage to yeast cells andEpistilys speciesdue to mechanical effects of cavitation such as microjets and shear forces. The observed cell ruptures and cracks were sufficient for the release of small soluble biologically relevant dissolved organic molecules into the bulk liquid, but not for the release of microbial DNA. Cavitation treatment also decreased total Pb concentrations by 70%, which was attributed to the reactions triggered by the chemical effects of cavitation. Additionally, the study confirmed the presence of microplastic particles and fibers of polyethylene, polyethylene terephthalate, polypropylene,and nylon 6 in the waste activated sludge.

There is a lack of knowledge regarding the parameters needed for the effective seismic performance assessment of historical stone masonry buildings. The paper presents the results of an extensive experimental campaign consisting of four compression and fifteen in-plane cyclic shear tests on three-leaf ashlar stone masonry walls and its constituents. The morphology, level of vertical load, and testing boundary conditions were systematically varied, and their influence on the load-bearing and deformation capacities, stiffness, ductility and energy dissipation was analysed. Good consolidation of the inner core enables in-plane failure mechanism of the walls to occur without decisive out-of-plane damage. The boundary conditions applied significantly influence the failure modes and large deformation capacities obtained, whereas transverse connections in the case of a shear failure mechanism do not significantly influence the overall lateral in-plane response of walls.

This chapter is composed of three parts. The first outlines socio-historic processes of the “real existing socialism” in Yugoslavia and shows how the deadlocks of transition to socialism led to restoration of capitalism. The second and third parts analyze the restoration in Slovenia and Croatia respectively, and the first 30 years of capitalist development. The balance sheet of the analysis is two-fold. On the one hand, it shows that restoration could result in different varieties of capitalism both because of different starting points and of deliberation of social forces. On the other hand, it indicates that both societies converge in the direction of a markedly peripheral capitalism, which produces similar challenges for left-wing forces.

This study investigates timber connections with flexible polyurethane adhesives, which prove to have the po-tential for timber-adhesive composite structures without mechanical connections for seismic regions. Results of conducted cyclic double lap-shear adhesive timber joints tests were compared with available experimental re-sults on timber connections with standard mechanical dowel-type fasteners and with results of numerical finite element analysis. The study found that the shear strength, elastic stiffness and strength degradation capacity of the flexible adhesive connections were significantly higher compared to mechanical fasteners commonly used in seismic-resistant timber connections. The latter, however, manifested larger ultimate displacements but also yielded at lower displacements. Nasl. z nasl. zaslona. Opis vira z dne 26. 10. 2021. Št. članka: 113125. Abstract. Bibliografija: str. 11-12.