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Dopolnjevanje stavkov v narečju
No full textDopolnjevanje stavkov je uveljavljena vrsta psiholingvistične raziskave jezikovnega izražanja, ki smo jo v slovenščini razvili kot del projekta Usvajanje manjšinskega jezika v večjezičnem okolju (J6-3130), ki ga sofinancira Javna agencija za raziskovalno dejavnost Republike Slovenije
Narrowband-light-triggered photothermal CO2 desorption from monolithic sorbents
No full textThe widespread deployment of Carbon Capture, Utilisation and Storage (CCUS) technology faces many challenges, where high operating costs are one of the main barriers. While significant research is dedicated to more efficient CO2 sorption, a shortage exists in developing cost-effective desorption methods. The most applied CO2 desorption method is the temperature swing method (TSM), involving heating the entire reactor > 100 °C for extended periods, resulting in high energy consumption.
An alternative approach to reduce energy demand during desorption is utilising light, which, combined with photothermal (PT) nanoparticles, can be converted into heat. Contrary to TMS, the PT approach allows precise and localised gas desorption due to the material’s inherent properties. Since PT nanoparticles display narrow absorption peaks, to achieve maximum PT effect with the lowest given power, precise light sources with concentrated power are required. Still, the main challenge of the PT approach is to reach a temperature > 100 °C for complete CO2 desorption and long-lasting cyclability.
The Peak Absorption Targeted Photothermal Desorption concept is a novel approach which uses low-energy, narrowband light sources—preferably at wavelengths corresponding to the peak absorption (λmax) of thermally stable photothermal (PT)-active monolithic sorbents—to efficiently desorb CO2. By optimizing light-to-heat conversion, this approach aims to achieve complete CO2 desorption with up to 90% less energy consumption compared to traditional thermal management systems (TMS)
Odziv mikrobov na antropogene motnje v Tržaškem zalivu (severni Jadran)
Get PDFMarine ecosystems are constantly influenced by anthropogenic pressures, including inputs of nutrients, pollutants, and allochthonous microorganisms. These inputs can disrupt the dynamics of marine microbiomes, which encompass the majority of biomass and highest diversity of all life forms, controlling most biogeochemical cycles in the ocean realm. Despite their importance for public safety and potential influence on marine ecosystems functioning, knowledge of the impact of these perturbations on coastal microbiome dynamics remains in its infancy. The research objectives of this dissertation were to: (1) characterize the composition of the coastal microbiome in anthropogenically impacted coastal ecosystem(2) investigate the genetic potential of selected microorganisms for pathogenicity and ecological adaptationsand (3) explore the effects of wastewater on the dynamics and functioning of the coastal microbiome, as well as its implications for the biogeochemical state of the ecosystem.
To address the first aim, we conducted a year-round in situ survey of the pelagic microbiome within anthropogenically impacted coastal ecosystem, focusing on the seasonal and spatial dynamics of traditional and alternative faecal bacterial indicators. We used a culture-independent approach combined with 16S rRNA amplicon sequencing, which overcome limitations of culture-based methods. This analysis revealed that the microbiome was primarily structured by seasonal changes, regardless of proximity to pollution sources. The statistical tool and oceanographic model we applied indicated that riverine water serves as a key vector for introducing allochthonous microbes. This study underscores the importance of molecular approaches combined with statistical and oceanographic modelling for advancing environmental health assessments and detecting microbial indicators.
To address the second aim, we applied whole-genome sequencing to assess the pathogenic potential and genomic features of selected Vibrio isolates. During the analysis, we identified cross-contamination in one isolate, which presented an opportunity to evaluate the effectiveness of bioinformatics workflows for contaminant removal and genome recovery. We reconstructed high-quality genomes of one Vibrio isolate from both axenic and contaminated cultures. Genomic analyses revealed that this isolate belongs to a sub-lineage of Vibrio campbellii associated with diseases in marine organisms. Moreover, this genome harboured a novel Vibrio plasmid linked to bacterial defense mechanisms and horizontal gene transfer, potentially offering a competitive advantage to this putative pathogen. This study highlights the utility of WGS and advanced bioinformatics in overcoming challenges posed by non-axenic cultures and provides new insights into the genomic characteristics of V. campbellii.
To address the third aim, we conducted a short-term microcosm experiment simulating wastewater discharge into coastal seawater, testing two types of wastewaters: (a) unfiltered, containing nutrients, pollutants, and allochthonous microbes, and (b) pre-filtered, retaining only nutrients and pollutants. Our results showed that wastewater, significantly increased nutrient levels (dissolved organic carbon, ammonium, orthophosphate). Using a multi-omics approach with measurements of microbial metabolic activity, we found that nutrient enrichment significantly influenced bacterial metabolism. This was evidenced by enriched protein profiles and increased leucine aminopeptidase and olease activity, indicating bacterial degradation of complex proteins and lipids. At the same time, the phosphate input resulted in a decreased alkaline phosphatase activity, with important implications for phosphorus cycling. Overall, wastewater primarily induced functional shifts in coastal microbiomes, highlighting the resilience and functional redundancy of coastal microbial communities and hence the biogeochemical processes they operate.Obalni morski ekosistemi so nenehno podvrženi številnim antropogenim pritiskom, kot je vnos hranil, onesnaževal in alohtonih mikroorganizmov. Ti vnosi lahko vplivajo na dinamiko morskih mikrobiomov, ki predstavljajo večino biomase in najbolj raznolike življenjske oblike ter vplivajo na kroženje snovi v morju. Kljub njihovemu pomenu za zdravje in dobrobit ljudi ter vplivu na delovanje morskih ekosistemov, je poznavanje vpliva teh pritiskov na dinamiko mikrobiomov v obalnih morjih pomanjkljivo. Raziskovalni cilji te disertacije so bili: (1) opredeliti sestavo obalnega mikrobioma v ekosistemu, ki je podvržen številnim antropogenim pritiskom(2) raziskati genetski potencial izbranih mikroorganizmov za patogenost in prilagodljivost na spremembe v okoljuin (3) raziskati učinke odpadne vode na dinamiko in delovanje obalnega mikrobioma ter posledično na kroženje snovi v morju.
Za dosego prvega cilja smo izvedli in situ meritve v obalnem morju, ki je izpostavljen številnim antropogenim pritiskom. Osredotočili smo se na spremljanje sezonske in prostorske dinamike tradicionalnih in alternativnih bakterijskih indikatorjev fekalnega onesnaženja. V naši študiji smo sekvencirali pomnožke gena za 16S rRNA, ki lahko preseže omejitve tradicionalno uporabljenih metod, ki temeljijo na gojenju mikroorganizmov. Ta analiza je pokazala, da se je struktura obalnega mikrobioma spreminjala glede na sezono, ne glede na bližino virov onesnaženja z odpadno vodo. Z uporabo statističnih orodji in oceanografskega modeliranja smo pokazali, da je onesnažena rečna voda, vektor za vnos alohtonih mikroorganizmov v morski ekosistem. Rezultati študije kažejo na pomen uporabe molekularnih pristopov v kombinaciji s statističnim in oceanografskim modeliranjem za boljše odkrivanje in sledenje bakterijskih indikatorjev fekalnega onesnaženja.
Za dosego drugega cilja smo uporabili metodo sekvenciranja celotnega genoma, ki nam je omogočila vpogled v potencialno patogenost in genomske značilnosti izbranih izolatov Vibrio. Med analizo smo pri enem od izolatov identificirali navzkrižno kontaminacijo, kar nam je ponudilo priložnost za preizkus učinkovitosti bioinformatskih analiz pri sestavljanju bakterijskega genoma iz vzorcev, ki so bili podvrženi kontaminaciji. Rekonstruirali smo dva visokokakovostna genoma izolata Vibrio – enega iz aksenične in enega iz kontaminirane kulture. Genomske analize so pokazale, da ta izolat pripada podliniji Vibrio campbellii, ki jo povezujemo z boleznimi morskih organizmov in vsebuje nov Vibrio plazmid, povezan z obrambnimi mehanizmi in horizontalnim prenosom genov, kar ponuja konkurenčno prednost v okolju. Ta študija poudarja uporabnost analize celotnega genoma pri premagovanju izzivov, ki jih predstavljajo nečiste kulture, in zagotavlja nov vpogled v genomske značilnosti V. campbellii.
Za dosego tretjega cilja, smo izvedli obogatitveni poskus, s katerim smo posnemali scenarij izpusta odpadne vode v obalno morje. Testirali smo vpliv dveh vrst odpadne vode na dinamiko obalnega mikrobioma: (a) nefiltrirano, ki vsebuje hranila, onesnaževala in alohtone mikrobe, in (b) filtrirano, ki vsebuje samo hranila in onesnaževala. Naši rezultati so pokazali, da je dodatek odpadne vode, znatno povečal raven hranil, zlasti raztopljenega organskega ogljika, amonija in ortofosfata. Z uporabo multiomičnega pristopa, ki je vključeval uporabo metagenomike in metaproteomike in meritve presnovne aktivnosti mikrobov, smo ugotovili, da je obogatitev s hranili pomembno vplivala na presnovo bakterij. To so dokazali obogateni proteinski profili in povečana aktivnost levcin aminopeptidaze in oleaze, kar kaže na bakterijsko razgradnjo kompleksnih beljakovin in lipidov, ki izvirajo iz odpadne vode. Istočasno je vnos fosfata povzročil zmanjšanje aktivnosti alkalne fosfataze, ki igra pomembno vlogo v kroženju fosforja v okolju. Rezultati vnosa odpadne vode v morsko vodo so pokazali spremembe v delovanju obalnih mikrobiomov in vpliv na biokemične procese, ki jih vršijo
Cluster-lensed supernova yields from the Vera C. Rubin Observatory and Nancy Grace Roman Space Telescope
Get PDFThrough gravitational lensing, galaxy clusters can magnify supernovae (SNe) and thereby create multiple images of the same SN. This enables measurements of cosmological parameters (primarily the Hubble constant), which will be increasingly important in the context of upcoming surveys from the Nancy Grace Roman Space Telescope ( Roman ) and Vera C. Rubin Observatory. We study the prospects of detecting strongly lensed supernovae in cluster fiels with Roman \u27s High Latitude Time Domain Survey (HLTDS) and the Vera C. Rubin Observatory\u27s Legacy Survey of Space and Time (LSST). We employed two approaches: one focusing on known multiply imaged galaxies (arcs) behind cluster fields, along with the SN rates specific to those galaxies (arc-specific), while the second is based on the expected number of lensed SNe exploding in a given volume behind a galaxy cluster (volumetric). We collected all the clusters in the literature that feature a) a well-constrained lens model and b) multiply imaged galaxies behind clusters with high-quality data for the multiply imaged galaxies behind clusters. This allowed us to determine the supernova rate for each galaxy. We provide predictions for 46 clusters visible to the Vera C. Rubin Observatory, as well as for 9 observable by Roman ’s HLTDS, depending on whether the clusters fall within the survey’s observing field. We predict that the number of multiply imaged SNe discovered by LSST in its first three years is from the first approach or from the second. Based on the current proposed observing strategy for the HLTDS, which specifies the requirements on galactic and ecliptic latitudes, the expected number of multiply imaged supernovae ranges from to , depending on the specific cluster observed. However, the exact fields to be targeted remain a matter of discussion. We conclude that LSST offers great prospects for detecting multiply imaged SNe. If adequate follow-up campaigns are conducted, these capabilities will enable measurements of cosmological parameters independent of conventional probes. These predictions are effectively lower limits, as we only considered the most massive and well-studied clusters in the present work. Here, we provide a recommendation for HLTDS observing field selection, namely: either MACS J0553.4-3342 or Abell 1758a should be observed by the survey to maximize the number of potential multiply imaged SN discoveries
Multimessenger studies with the Pierre Auger Observatory
Get PDFThe Pierre Auger Observatory, the world’s largest ultra-high-energy (UHE) cosmic ray (CR) detector, plays a crucial role in multi-messenger astroparticle physics with its high sensitivity to UHE photons and neutrinos. Recent Auger Observatory studies have set stringent limits on the diffuse and point-like fluxes of these particles, enhancing constraints on dark-matter models and UHECR sources. Although no temporal coincidences of neutrinos or photons with LIGO/Virgo gravitational wave events have been observed, competitive limits on the energy radiated in these particles have been established, particularly from the GW170817 binary neutron star merger. Additionally, correlations between the arrival directions of UHECRs and high-energy neutrinos have been explored using data from the IceCube Neutrino Observatory, ANTARES, and the Auger Observatory, providing additional neutrino flux constraints. Efforts to correlate UHE neutron fluxes with gamma-ray sources within our galaxy continue, although no significant excesses have been found. These collaborative and multi-faceted efforts underscore the pivotal role of the Auger Observatory in advancing multi-messenger astrophysics and probing the most extreme environments of the Universe
Sexuality and the configurations of masculinity in twentieth-century Slovene male-authored writing
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Mass composition of ultra-high-energy cosmic rays at the Pierre Auger Observatory
Get PDFFor the past 20 years, the Pierre Auger Observatory has collected the largest dataset of
ultra-high-energy cosmic rays (UHECRs) ever achieved using a hybrid detector. The study
of this dataset has led to numerous unexpected discoveries that enhance our understanding
of the origins of UHECRs. One of the key points in this study is their mass composition.
In this work, we will present the most recent results regarding the mass composition of UHECRs at the Pierre Auger Observatory. In particular, we will focus on the measurement of the depth
of the maximum of air-shower profiles, denoted as Xmax . This determination has been achieved through both direct measurements from the Fluorescence Detector data and the application of machine learning for estimating Xmax on an event-by-event basis using the Surface Detector data. The latter has allowed us to extend the measurement to energies up
to 100 EeV and indicates a correlation between changes in composition and three features
of the energy spectrum (ankle, instep, steepening). Moreover, the results provide evidence
of a heavy and nearly pure primary beam for energies greater than 50 EeV that is independent
of the hadronic interaction model. The implications of these findings for astrophysics and
for modelling hadronic interactions will be discussed