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Dynamic behaviour of energy transfer station real field performance compared to ideal laboratory conditions
No full textDistrict energy is one of the most efficient heat distribution systems. The interface between the pipe network and buildings is made of thermal and hydraulic separation units named stations. The control of temperature on the secondary side is handled in substations. Several parameters influence control stability, such as differential pressure, mass flow, temperatures, valve inherent characteristics and controller tuning. There are different design approaches for stations in different geographies. However, one option is a generalist control loop setup, which is analysed here. Four sites in Sweden were monitored for performance (during the winter period and with the same hardware setups), and an analysis of the variability of controller tuning parameters was performed. For the purposes of laboratory comparison, the tests were executed with different configurations of generic control loop setups. The results, arranged into distribution histograms, show similarities between the laboratory and field setups. One can see that well-performing setups are close to a normal distribution, while the others are not. One key parameter is the controller setup and algorithm used. Proper tuning of the controller, together with differential pressure control, secures optimal performance of district energy stations. District heating stations with operations closer to the set point positively influence the performance of the whole grid and therefore improve the energy efficiency of the stations
Analysis of sugars, amino acids and phenolic compounds in the nectar of selected native melliferous plant species
No full textV raziskavi smo preučevali nektar dvanajstih avtohtonih medovitih rastlinskih vrst. Zanimala nas je količina izločenega nektarja in njegova sestava, predvsem sladkorji, aminokisline ter fenolne spojine. Preučili smo tudi vpliv dela dneva na nektar in vpliv abiotskih dejavnikov, kot so temperatura zraka ter prsti, vlažnosti prsti in zraka ter UVB sevanje. Vzorce nektarja smo pridobili z metodo s kapilarami in pranja cvetov v naravnem okolju v Ljubljani ter okolici. Preverili smo, ali sta obe metodi zbiranja nektarja res zanesljivi in uporabni za globoke ter plitve cvetove in ugotovili, da je metoda s kapilarami bolj zanesljiva, ampak z manjšimi omejitvami pri plitvih cvetovih. Ugotovili smo tudi, da del dneva vpliva na količino izločanja nektarja in tudi na koncentracijo sladkorjev, aminokislin ter fenolnih spojin, ne pa toliko na sama razmerja posameznih snovi. Vpliv na izločanje nektarja in določene snovi imajo tudi vsi preiskovani abiotski dejavniki. Ugotovili smo tudi, da se sestava nektarja razlikuje med vrstami in družinami, predvsem se razlikuje izločanje nektarja, ki je povezano predvsem z vplivom dela dneva oziroma vplivom abiotskih dejavnikov. Na podlagi raziskave lahko sklepamo, katere rastlinske vrste predstavljajo za opraševalce boljšo pašo.In this study, we investigated the nectar of twelve native plant species. Our focus was the quantity of nectar secretion and its chemical composition (sugars, amino acids, and phenolic compounds). We further examined the influence of diurnal variation on nectar production, as well as the effects of abiotic factors, including air and soil temperature, soil and air humidity, and UVB radiation. Nectar samples were collected using both the capillary method and flower washing under natural field conditions in Ljubljana and its surroundings. We evaluated the reliability and applicability of both sampling techniques for flowers of varying corolla depths and determined that the capillary method is generally more reliable, with certain limitations in shallow flowers. Our results indicate that the time of day significantly affects both the quantity of nectar secreted and the concentrations of compunds. All examined abiotic factors were also found to influence nectar secretion and, to some extent, the concentration of individual compounds. Additionally, we observed species- and family-level differences in nectar composition, with the most pronounced variation observed in nectar secretion rates, which were largely driven by diurnal and abiotic factors. Based on these findings, we can infer which plant species represent more valuable forage for pollinators
Blind prediction and post-experimental analysis of RC core wall’s cyclic flexural response using MVLEM-FD
No full textBlind prediction and post-experimental studies of the flexural cyclic response of a U-shaped core wall, tested at UCLouvain, Belgium, are presented. The tested specimen (referred to as UW1) was modelled using a relatively simple 3D force–displacement-based version of the beam–column multiple-vertical-line-element (MVLEM-FD), developed at the University of Ljubljana (UL), using standard element parameters. The blind prediction accurately identified critical failure points within the specimen. However, the predicted type of failure, attributed to the rupture of longitudinal bars in the boundary region of flanges was somewhat different from that observed in the experiment. These bars were indeed ruptured, but their rupture was preceded by their buckling and the spalling of the surrounding concrete core. Moreover, the predicted force–displacement hysteretic loop exhibited a slight shift compared to experimental observations. Post-experimental studies revealed that this discrepancy was primarily due to the modelling of the loading at the top of the wall rather than the modelling of the wall itself. Specifically, an additional bending moment induced by the eccentricity of the vertical load applied using three actuators, which was overlooked in the blind prediction. Upon correcting the loading, the agreement between the numerical studies and experiment was considerably improved in terms of both the global and local response quantities. Additionally, minor improvements in modelling the boundary regions of the wall’s flanges, considering the relatively large unconfined concrete cover, were introduced, leading to enhanced estimations of near-collapse response
Autoreferentiality and representation of trans identity in Las malas by Camila Sosa Villada
No full textV raznolikem prostoru sodobne latinoameriške književnosti je vse opaznejša prisotnost marginaliziranih glasov, med katerimi izstopa tudi trans narativa, ki se uveljavlja kot oblika upora proti prevladujočim literarnim smernicam. Magistrsko delo se osredotoča na roman Las malas (2019) argentinske pisateljice Camile Sosa Villada, v katerem se skozi zgodbo protagonistke oblikuje njena identiteta – tako na individualni, kot tudi na kolektivni ravni. Analiza izhaja iz hipoteze, da avtorica uporabi avtofikcijo in avtoreferencialnost kot pripovedni tehniki, ki omogočata gradnjo in odkrivanje lastne identitete, hkrati pa dajeta glas celotni skupnosti transvestitk. Skozi interpretativni pristop se raziskujejo tri glavne točke: pisava ‘jaza’ na stičiščih avtobiografije, avtofikcije in avtoreferencialnostioblikovanje identitete protagonistke v kontekstu družinskega nasilja, družbene izključenosti in spolnega dela ter prikaz skupnosti transvestitk kot oblike podpore, solidarnosti in medsebojne skrbi. Roman razkriva, kako književnost lahko deluje kot orodje vidnosti, kritike in upora. V tem smislu magistrsko delo povzema, da Camila Sosa Villada predstavlja mejnik v sodobni trans književnosti, saj ponuja kompleksen prikaz transvestitske identitete ter ji daje glas.In the diverse landscape of contemporary literature, there is a growing visibility of marginalised voices, including trans narratives, which are exhibiting themselves as spaces of resistance against established literary discourses. This master\u27s thesis focuses on the novel Las malas (2019) by the Argentine writer Camila Sosa Villada, which articulates the construction of both individual and collective identity. The analysis is based on the hypothesis that the author uses autofiction and autoreferentiality as narrative strategies that allow her to reconstruct and rediscover her own transvestite identity, while simultaneously giving voice to an entire transvestite community. Through an interpretative approach, three main points are studied: the writings of the ‘self’ at the intersection of autobiography, autofiction and autoreferentialitythe configuration of the protagonist\u27s identity in a context marked by family violence, social exclusion and sex workand the representation of the transvestite community as a network of support, solidarity and mutual care. The novel demonstrates how literature can function as a tool of visibility, criticism and resistance. In this sense, the work concludes that Camila Sosa Villada\u27s narrative constitutes a milestone in contemporary trans literature, offering a complex representation of transvestite identity, giving it agency and voice
Analysis of expression levels and cellular localization of enolase isoforms in reactivated C8D1A astrocytic cells
No full textAstrociti spadajo med celice glije, ki se nahajajo v centralnem živčnem sistemu, kjer imajo pomembno vlogo v homeostazi in pri imunskemu odgovoru. Pod vplivom raznih vnetnih in patoloških stimulusov se lahko astrociti reaktivirajo v vnetni fenotip A1, ki pospešuje vnetne spremembe, ali pa v protivnetni fenotip A2, ki v možganih deluje zaščitno. Nekatere izooblike encima enolaze, ki jih izražajo tudi astrociti, izkazujejo nevrotrofične učinke, ki so pomembni z vidika preprečevanja nevrovnetja in nevrodegenerativnih sprememb, vendar vloga enolaze v astrocitih še ni razjasnjena. V okviru magistrske naloge smo želeli opredeliti ravni izražanja in določiti celično lokalizacijo izooblik enolaze v reaktiviranih astrocitih. Najprej smo postavili celični model reaktiviranih astrocitov z uporabo celične linije astrocitov C8-D1A, kjer je bil cilj pokazati vpliv stimulacije celic C8-D1A z lipopolisaharidom (LPS) in kondicioniranim gojiščem mikroglije BV2 (MCM) na reaktivacijo astrocitov v vnetni fenotip. Pri tem se je izkazal MCM za učinkovitejšega, kar smo pokazali z opazovanjem morfologije celic C8-D1A in vrednotenjem vpliva stimulacije na celično preživetje, hitrost proliferacije in na sproščanje vnetnih mediatorjev v celicah astrocitov. Nadalje smo opredelili raven izražanja in znotrajcelično lokalizacijo α- in γ-enolaze v reaktiviranih celicah C8-D1A. Izpostavitev MCM, ne pa tudi LPS, je povišala izločanje izooblik enolaze z večjim izločanjem izooblike γ, medtem ko se raven znotrajcelične enolaze ni značilno spremenila, kar smo pokazali s testom ELISA. V zadnjem delu magistrske naloge smo vrednotili še vpliv ireverzibilnega zaviralca katepsina X, AMS36, in sinteznih peptidov α- in γ-enolaze na reaktivacijo astrocitov. Pokazali smo, da je AMS36 z zaviranjem katepsina X po izpostavitvi MCM preprečil prehod astrocitov v vnetni fenotip A1, kar se je pokazalo v morfologiji celic in pri upadu aktivnosti kaspaze-3, hkrati pa se je prisotnost zaviralca odražala v povišani ravni aktivne oblike γ-enolaze. Podobne rezultate smo dobili pri poskusih s sinteznimi peptidi, ki posnemajo C-končni del enolaze. Pridobljeni rezultati nakazujejo na pomembno vlogo izooblik enolaze in uravnavanje ravni aktivne oblike γ-enolaze s katepsinom X pri prehodu astrocitov v vnetni fenotip A1, s čimer bi razvoj spojin, ki bi spodbujale nevrozaščitno delovanje α- in γ-enolaze imel doprinos pri terapiji vnetnih in nevrodegenerativnih sprememb v osrednjem živčevju.Astrocytes are glial cells located in the central nervous system, where they play a crucial role in maintaining homeostasis and mediating immune responses. Under the influence of various inflammatory and pathological stimuli, astrocytes can become reactivated into either a pro-inflammatory A1 phenotype, which promotes inflammatory changes, or an anti-inflammatory A2 phenotype, which has protective effects in the brain. Some isoforms of the enzyme enolase, also expressed by astrocytes, exhibit neurotrophic properties important for preventing neuroinflammation and neurodegenerative alterationshowever, the precise role of enolase in astrocytes has not yet been clarified. In this master’s thesis, we aimed to define the expression levels and determine the cellular localisation of enolase isoforms in reactivated astrocytes. We first established a cellular model of reactive astrocytes using C8-D1A astrocyte cell line, with the goal of demonstrating the effect of stimulation with lipopolysaccharide (LPS) and BV2 microglia-conditioned medium (MCM) on astrocyte reactivation into a pro-inflammatory phenotype. MCM proved to be more effective, as shown by morphological observations of C8-D1A cells and the evaluation of the effect of stimulation on cell survival, proliferation rate, and the release of inflammatory mediators in astrocyte cells. We then assessed the expression levels and intracellular localisation of α- and γ-enolase in reactivated C8-D1A cells. Exposure to MCM, but not to LPS, increased the secretion of enolase isoforms, particularly the γ isoform, while the intracellular levels of enolase did not significantly change, as shown by ELISA analysis. In the final part of the thesis, we examined the effects of the irreversible cathepsin X inhibitor AMS36 and synthetic α- and γ-enolase peptides on astrocyte reactivation. We showed that AMS36, by inhibiting cathepsin X following exposure to MCM, prevented the transition of astrocytes into the pro-inflammatory A1 phenotype, as evidenced by cell morphology and a decrease in caspase-3 activity, while the presence of the inhibitor was associated with an increased level of the active γ-enolase form. Similar results were obtained in experiments with synthetic peptides that mimic the C-terminal region of enolase. The obtained results indicate an important role of enolase isoforms and the regulation of the active form of γ-enolase by cathepsin X in the transition of astrocytes to the pro-inflammatory A1 phenotype, thus the development of compounds that would promote the neuroprotective activity of α- and γ-enolase would contribute to the therapy of inflammatory and neurodegenerative conditions of the central nervous system
Sustainable production and characterization of ZnO–GO nanocomposites from waste Zn–C batteries for photocatalytic degradation of malachite green
No full textIn this study, ZnO–GO nanocomposites were synthesized from waste Zn–C batteries and used for the photocatalytic degradation of malachite green (MG) under UV light. ZnO–GO nanocomposites with different GO contents (1, 2.5, and 5 wt%) were prepared at room temperature and characterized by XRD, SEM, EDS, and UV–Vis spectroscopy. The GO content significantly affects the morphology, optical properties, and photocatalytic activity of the nanocomposites. In the presence of ZnO NPs, a malachite green degradation efficiency of 96.25% was achieved in 90 min, while ZnO–1%GO, ZnO–2.5%GO, and ZnO–5%GO achieved 95.35%, 97.27%, and 99.6% MG degradation, respectively, in just 30 min. The photocatalytic degradation process of MG was optimized using Response Surface Methodology (RSM). The effects of GO content, catalyst dosage, initial MG concentration, and irradiation time on the efficiency of photocatalytic degradation were investigated, and optimal conditions were determined. Under optimal conditions, a photocatalytic degradation efficiency of 98.51% was achieved. These results indicate that ZnO–GO nanocomposites synthesized from waste Zn–C batteries are efficient and environmentally friendly photocatalysts for the treatment of dye-contaminated wastewater
The variability of spoken language in sociolinguistic research
No full textPrispevek izpostavlja pomen celovitejših raziskav govorjenega jezika ter predstavlja različno obsežne in metodološko različno zasnovane sociolingvistične raziskave jezikovne variantnosti v Avstriji, Nemčiji, Belgiji in na Madžarskem. Pri tem se osredotoča na izbor informantov, kontekste pridobivanja posnetkov, načine obdelave podatkov, po možnosti širši sociolingvistični kontekst in glavne ugotovitve. Opisani projekti lahko služijo kot izhodišče pri načrtovanju nadaljnjih raziskav na slovenskem gradivu, potreba po katerih je bila večkrat izražena in ki lahko prispevajo k bolj celostni podobi in razumevanju variantnosti govorjene slovenščine in njenih sprememb ter povezave med jezikom in družbo v sodobnosti.The article highlights the importance of comprehensive studies on spoken language, and presents various sociolinguistic research projects on language variation in Austria, Germany, Belgium, and Hungary. It focuses on the selection of informants, contexts of data collection, data analysis methods, the broader sociolinguistic context, and main findings. The described projects can serve as a starting point for planning further research on Slovene materials, addressing the expressed need for a more comprehensive understanding of the variation and change in spoken Slovene, and the relationship between language and society in the contemporary context
An open-label randomized controlled trial comparing the efficacy and safety of a 7-day triple therapy with bismuth versus 14-day standard triple therapy for Helicobacter pylori eradication in children and adolescents
No full textBackground: To achieve eradication rates >90%, the ESPGHAN/NASPGHAN guidelines for pediatric Helicobacter pylori infection recommend tailored antimicrobial therapy using sufficiently high doses over 10–14days. However, prolonged treatment often leads to suboptimal compliance in children, which is a major contributor to reduced eradication rates. To address this, we evaluated the efficacy and safety of a shorter, 7day triple therapy with bismuth compared with the 14day standard triple therapy without bismuth in H. pylori infected children.
Materials and Methods: From 2020 to 2024, we carried out a randomized controlled trial involving treatment-naïve children and adolescents (5–18 years old) with confirmed H. pylori infection. Eligible participants were randomly allocated to receive either a 7day triple therapy with bismuth (bismuth subcitrate, a proton pump inhibitor [PPI], amoxicillin, plus clarithromycin/ metronidazole) or a 14day standard triple therapy (a PPI, amoxicillin, plus clarithromycin/metronidazole) without bismuth. Two months after completing therapy, treatment success was determined using either a two-step monoclonal stool antigen assay or a urea breath test. Any adverse events were documented using a structured questionnaire.
Results: Seventy-three children were enrolled in the study. In the intention-to-treat analysis, eradication was achieved in 91% of children treated with the 7day triple therapy with bismuth and 87% of those receiving the 14day standard triple therapy (p=0.695). Per-protocol eradication rates were 94% and 87%, respectively (p=0.418). No serious adverse events were reported, and most adverse events were mild to moderate. A metallic taste was significantly more frequent in the 14day standard triple therapy group, while other adverse events occurred with similar frequency.
Conclusions: Adding bismuth to a 7day triple regimen achieved high eradication rates and a safety profile similar to 14day standard triple therapy, supporting its use as an effective and safe treatment option for pediatric H. pylori infection
A fourth-order phase-field model of crack initiation and propagation under thermomechanical loading solved with strong-form meshless method
No full textThis study aims to develop a combination of the fourth-order phase-field method (PFM) and a strong-form meshless solution procedure for crack initiation and propagation under thermomechanical loading in two-dimensional brittle elastic material. The formulation involves thermal, mechanical and fourth-order phase-field equations. A spectral-split method decomposes the elastic strain tensor for physically correct crack propagation under mixed-mode thermomechanical loading conditions. The three coupled equations are solved in a staggered form. The domain discretization is based on regular or scattered nodes, overlapping subdomain division of the domain, and interpolation of the involved subdomain fields using third-order polyharmonic splines combined with second-order polynomial augmentation. The three numerical benchmarks include the pure thermal case, single-edge crack propagation under combined thermomechanical loading and quenching. The suitability and robustness of the proposed meshless approach are demonstrated on both regular and scattered node arrangements, and the corresponding second-order h-convergence of the displacement fields was shown for the subdomains with 13 nodes. The scattered node arrangement more effectively captures crack propagation under complex loading conditions. The originality of this study is twofold. It represents a pioneering approach using the fourth-order PFM to the thermomechanical brittle elastic system and the first solution to the related physical situation by a meshless method. The proposed method possesses a strong performance in terms of accuracy. The required dense node arrangement around the crack influences its computational efficiency. Further study will include an adaptive node arrangement scheme to enhance computational efficiency, enabling the extension to three dimensions
Representation of authors in the academic monograph Literary atlas of Ljubljana, 2014
No full textThe interdisciplinary project entitled The Space of Slovenian Literary Culture, which was led by ZRC SAZU and ran from 2011 to 2014, was financed with public funds or ARIS. The project was led by Marko Juvan and his colleagues from the fields of literary studies (M. Dolgan, M. Dović, J. Habjan, A. Jež, A. Koron, M. Ogrin and J. Škulj, M. Hladnik, U. Perenič, B. Lampič) and geography. A monograph was also produced as part of the project, co-financed by the Slovenian Book Agency and the City of Ljubljana. Thefirst part of the monograph contains an explanation of the name Ljubljana, written by the etymologist Dr Silvo Torkar. The website Space of Slovenian Literary Culture (http://pslk.zrc-sazu.si/sl/o-projektu/) provides detailed information about the project, spatial analyses, the Atlas and related projects