21. Experimental and numerical study of Taylor bubble in counter-current turbulent flowIztok Tiselj, Jan Kren, Blaž Mikuž, Raksmy Nop, Alan Burlot, Grégoire Hamrit, 2025, izvirni znanstveni članek Povzetek: The stagnant Taylor bubble in vertical isothermal turbulent counter-current flow was analyzed using 2D shadowgraphy experiments and two distinct high-fidelity numerical simulations. One simulation employed the geometrical VOF interface tracking method within the OpenFOAM code, while the other utilized the explicit front tracking method of the TrioCFD code. Interface recognition algorithms were applied to the photographs and compared with the results of 3D simulations performed with LES and pseudo-DNS accuracy in OpenFOAM and TrioCFD, respectively. The measured Taylor bubbles exhibited an asymmetric bullet-train shape and a specific speed, which were compared with the predictions of both numerical approaches. Reproducing the experiment proved challenging for both otherwise well-established methods frequently used in interface tracking simulations of two-phase flows. Grid resolution and subgrid turbulent models, known for their success in single-phase turbulence, were less accurate near the water–air interface. Additional experimental parameters compared with simulations were related to the dynamics of tiny disturbance waves with amplitudes ranging from 10 to 100 µm along the interface of the Taylor bubbles. The speed and spectra of the surface disturbance waves were reproduced numerically with moderate success despite detailed grid refinement in the relevant region of the computational domain.
Ključne besede: gas–liquid mixture flows, slug flow, Taylor bubble, shadowgraphy, front tracking
Objavljeno v DiRROS: 10.04.2025; Ogledov: 40; Prenosov: 19
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22. Microclimate variability impacts the coexistence of highland and lowland ectothermsUrban Dajčman, Urtzi Enriquez-Urzelai, Anamarija Žagar, 2025, izvirni znanstveni članek Povzetek: Understanding differences in life-history outcomes under variable abiotic conditions is essential for understanding species coexistence. At middle elevations, a mosaic of available sets of abiotic conditions could allow highland and lowland species of the same ecological guild to overlap. Therefore, these sites are excellent to study the influence of abiotic conditions on life history and, thus, spatial overlap patterns of competing species. To test differences in life-history outcomes, we selected a pair of closely related lacertids, Iberolacerta horvathi and Podarcis muralis, with an overlapping geographical range but a contrasting elevational distribution. To assess how abiotic and biotic factors contribute to the realized niches of both species, we first built dynamic energy budget (DEB) models for each species based on available functional and life-history data. Then, we used a mechanistic modelling framework (NicheMapR) to simulate the microclimatic conditions at 15 study sites across an elevational gradient and performed whole life-cycle simulations for both species to compare egg development times, lifespans, reproductive years, mean yearly basking and foraging times and yearly fecundity in syntopy and allotopy along the elevational gradient. Our simulations show that the variability of abiotic conditions along an elevational gradient affects life-history traits of both species. We found strong effects of species and elevation on life-history outcomes such as longevity, activity and fecundity. We also observed the effects of syntopy/allotopy on egg development times, activity and reproductive output. In addition, we found a significant interplay between elevation and species impacting fecundity where occupying higher elevation habitats resulted in a more pronounced reduction in fecundity in P. muralis. Furthermore, using two different thermal preferences for spring and summer, we show that some physiological and reproductive traits change with seasonal changes in thermal preferences. Based on our simulations, we conclude that the intermediate elevations that harbour the majority of syntopic populations exhibit high environmental variability that is likely facilitating species coexistence. Since our model predictions support that the current elevational distribution of the species is not only affected by abiotic factors, this suggests that past historical contingencies might have also played a significant role. Our study provides a framework using mechanistic models to understand current distribution patterns of two interacting species by comparing life-history differences between species based on responses to changing abiotic conditions along an elevation gradient.
Ključne besede: dynamic energy budget, ectotherms, elevation, Lacertidae, life history, microclimate, syntopy
Objavljeno v DiRROS: 10.04.2025; Ogledov: 29; Prenosov: 16
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23. Advancing nuclear research and education in Slovenia and EU : From operating the TRIGA reactor to building a new generation facilityJan Malec, Iztok Tiselj, Anže Pungerčič, Tanja Goričanec, Leon Cizelj, Luka Snoj, 2024, izvirni znanstveni članek Povzetek: The TRIGA Mark II research reactor at the Jožef Stefan Institute in Slovenia achieved first criticality in 1966. Since then, the reactor has been playing an important role in developing nuclear technology. The reactor has been mainly used for research, education of university students, training of operators of the Krško nuclear power plant (start of operation in 1983) and other nuclear specialists, isotope production and beam applications. The reactor is experiencing a high level of activity today, engaging in a diverse range of experiments and studies across reactor physics, environmental research, radiation hardness testing as well training and education. The future of nuclear technology in Slovenia is focused on new NPPs, while the research community is looking forward to a possible new nuclear reactor. The basic initiatives are at a very preliminary stage: the primary choice is dual-core pool-type reactor, with a zero-power core and a separate MW-size core, cooled and moderated with light water. Such a dual-core configuration is designed to meet the varied requirements of the European Union member states. Another option would be hosting one or more micro-reactors with electrical and/or heating power producing capability that could offer stronger support toward demonstration of prototype small modular reactors in prototype future electrical grids.
Objavljeno v DiRROS: 10.04.2025; Ogledov: 39; Prenosov: 12
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24. Analysis of the measurements used as potency tests for the 31 US FDA-approved cell therapy productsCarl G. Simon Jr., Erich H. Bozenhardt, Christina M. Celluzzi, David Dobnik, Melanie L. Grant, Uma Lakshmipathy, Thiana Nebel, Linda Peltier, Anthony Ratcliffe, James L. Sherley, 2025, pregledni znanstveni članek Povzetek: Cell therapy product (CTP) developers face the significant challenge of developing appropriate potency tests for their CTPs. A review of the known potency tests used for the 31 United States Food and Drug Administration-approved CTPs (US FDA) can guide developers in designing effective potency tests for future CTPs. Data on these tests were primarily collected from publicly available regulatory documentation on the US FDA website (90%) as well as other sources (literature, company communications, etc.). Based on these data, an estimated 104 total potency tests have been used for the 31 CTPs. Of these, 33 are redacted (32%), leaving 71 non-redacted potency tests. On average, each CTP has 3.4 potency tests (standard deviation 2.0). The 71 non-redacted potency tests were categorized into 5 bins: “Viability and count” (37 tests, 52%), “Expression” (19 tests, 27%), “Bioassays” (7 tests, 7%), “Genetic modification” (6 tests, 9%) and “Histology” (2 tests, 3%). Measurements of gene or protein expression were used by 20 of the 31 CTPs (65%), and 19 CTPs (61%) used measurements of cell viability or cell count as a potency test. “Viability and count” and “Expression” are the two tests that have most often been used together for the same product, occurring for 16 CTPs (52%). It is unclear if bioassays are commonly used as potency tests since only 7 of 31 CTPs (23%) reported bioassays as potency tests. However, due to redactions, as many 24 (77%) CTPs could potentially have a bioassay as a potency test. Additionally, 26 of the 31 CTPs (84%) cite physicochemical assays (non-bioassays) as a potency test. This analysis of potency tests for approved CTPs provides valuable insights for developing potency tests for new CTPs.
Ključne besede: cell therapy product, potency, potency test, regenerative medicine
Objavljeno v DiRROS: 10.04.2025; Ogledov: 36; Prenosov: 12
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25. Ethylene signaling is essential for mycorrhiza-induced resistance against chewing herbivores in tomatoJavier Lidoy, Javier Rivero, Živa Ramšak, Marko Petek, Maja Križnik, Victor Flors, Juan A Lopez-Raez, Ainhoa Martinez-Medina, Kristina Gruden, Maria J Pozo, 2025, izvirni znanstveni članek Povzetek: Arbuscular mycorrhizal (AM) symbiosis can prime plant defenses, leading to mycorrhiza-induced resistance (MIR) against different attackers, including insect herbivores. Still, our knowledge of the complex molecular regulation leading to MIR is very limited. Here, we showed that the AM fungus Funneliformis mosseae protects tomato plants against two different chewing herbivores, Spodoptera exigua and Manduca sexta. We explored the underlying molecular mechanism through genome-wide transcriptional profiling, bioinformatics network analyses, and functional bioassays. Herbivore-triggered jasmonate (JA)-regulated defenses were primed in leaves of mycorrhizal plants. Likewise, ethylene (ET) biosynthesis and signaling were also higher in leaves of mycorrhizal plants both before and after herbivory. We hypothesized that fine-tuned ET signaling is required for the primed defense response leading to MIR. ET is a complex regulator of plant responses to stress and is generally considered a negative regulator of plant defenses against herbivory. However, ET-deficient or insensitive lines did not show AM-primed JA biosynthesis or defense response, and were unable to develop MIR against any of the herbivores. Thus, we demonstrate that hormone crosstalk is central to the priming of plant immunity by beneficial microbes, with ET fine-tuning being essential for the primed JA biosynthesis and boosted defenses leading to MIR in tomato.
Ključne besede: chewing herbivores, defense priming, ethylene, hormonal crosstalk, jasmonate, mycorrhiza-induced resistance (MIR)
Objavljeno v DiRROS: 10.04.2025; Ogledov: 30; Prenosov: 17
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27. Pisava življenja : Ob pesništvu Paula CelanaAndrej Božič, 2022, znanstvena monografija Povzetek: Knjiga predstavlja prvo samostojno znanstveno monografijo spod peresa slovenskega avtorja o poeziji enega izmed najpomembnejših in najkompleksnejših evropskih pesnikov dvajsetega stoletja. Za izhodišče interpretativnega razpiranja raznoterih plasti Celanove besedne ustvarjalnosti monografiji služi (dolga, devetdelna) pesnitev »Engführung« iz zbirke Sprachgitter (1959), pri čemer se njeni posamezni deli prepletajo z razčlenitvijo knjige na poglavja. Po uvodnem, predstavitvenem poglavju, ki naznači namen razprave o mnogostranskih kontekstih kreativnosti v nemškem jeziku pišočega pesnika judovskega porekla, se avtor spoprime s filozofskim problemom slehernega pristopanja k literarni umetnosti, kakor ga je mogoče razgrniti ob soočenju med hermenevtiko Hansa-Georga Gadamerja, dekonstrukcijo Jacquesa Derridaja in fenomenologijo responzivne racionalnosti Bernharda Waldenfelsa. Predhodnost nagovora pesmi in naknadnost razlagalnega odgovarjanja tvorita dvojnostno gibanje, znotraj katerega se odigrava interpretativno mujenje ob »inter-(a)pelativnosti« umetniškega besedila. V nadaljevanju skuša avtor ob obravnavi posameznih pesmi pretresti nekatere poglavitne kontekste, kakršni so-opredeljujejo in se razpirajo skoz Celanovo ustvarjalnost. Samostojno poglavje se ukvarja s pesnikovimi načelnimi avto-poetološkimi razmišljanji, ki jih na odlikovan način pooseblja znameniti govor z naslovom »Meridian«. Celanova govorica s svojo značilno dialogičnostjo stopa v razgovor z raznolikimi perspektivami človekovega duhovnega udejstvovanja. Monografija se posveti predvsem trem osrednjim kontekstualnim okrožjem: medtem ko ob vprašanju filozofskega konteksta izpostavi konstitutivno razmerje Celanovega pesništva do mišljenja Martina Heideggra in medtem ko ob vprašanju literarnozgodovinskega konteksta podčrta pomen dela in usode Osipa Mandelštama za njegovo umetniško samorazumevanje, problemsko osvetli tudi zagato pesnikovega odnosa do njegovega lastnega porekla, do judovske tradicije, nezadržno zaznamovane z dogodkom holokavsta. Kolikor je vsakršen interpretativni poskus pogojen in predisponiran z zgodovinskim učinkovanjem, avtor posebno pozornost nakloni tudi odnosu sodobnega slovenskega pesništva do Celanove poezije, zlasti njeni plodni recepciji pri njenem prvem prevajalcu, Niku Grafenauerju. Zaključno poglavje, slednjič, knjigo sklene, povzemajoč pri tem prehojeno pot, z interpretativno komentarjem pesnitve »Engführung«. S samostojno monografsko obravnavo Celanovega pesništva skuša knjiga utreti pot novim spoznanjem znotraj slovenske literarne vede in hkrati opozoriti na nekatera temeljna filozofska vprašanja. Nemara leži posebna vrednost knjige v tem, da avtor predloži tudi svoje, nove prevode obravnavanih Celanovih pesniških del.
Ključne besede: literatura in filozofija, nemška poezija, literarna interpretacija, hermenevtika, judovstvo
Objavljeno v DiRROS: 10.04.2025; Ogledov: 44; Prenosov: 18
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