631. Visokogorska jezera v vzhodnem delu Julijskih Alp2002, scientific monograph Abstract: V knjigi, ki prinaša celovito predstavitev naših visokogorskih jezer, oceno njihovega ekološkega stanja in razlago dogajanj v njih skozi zgodovino, so zbrani rezultati več kot desetletnih raziskav 18 avtorjev. V delu je podan geografski opis in nastanek visokogorskih jezer, hidrološke povezave med njimi ter fizikalne in kemijske lastnosti jezerske vode. Opisano je življenje v njih in spremembe, ki so jih jezera doživela v zadnjih stoletjih, opozorjeno pa je tudi na problem onesnaževanja visokogorja.
Keywords: fizična geografija, hidrologija, rastlinstvo, živalstvo, onesnaževanje voda Published in DiRROS: 09.08.2024; Views: 483; Downloads: 208 Full text (5,72 MB) This document has many files! More... |
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633. Geografija stika Slovenske Istre in Tržaškega zaliva2018, scientific monograph Abstract: Znanstvena monografija na celosten način obravnava geografsko območje stika med kopnim, Slovensko Istro in morjem, Tržaškim zalivom. Stika med kopnim in morjem ne obravnava samo z vidika analize pokrajinotvornih prvin, loteva se tudi vpliva stika na fizično- in družbenogeografske pojave in procese in izpostavlja nekatere glavne izzive prebivalstvenega in gospodarskega razvoja, ob hkratnem upoštevanju ranljivosti obravnavane pokrajine, reševanja problematike obremenjevanja in onesnaževanja okolja ter širše rabe trajnostnega razvoja. Keywords: slovenska Istra, Tržaški zaliv, regionalna geografija Published in DiRROS: 08.08.2024; Views: 279; Downloads: 179 Full text (161,08 MB) This document has many files! More... |
634. Izzivi razvoja ribištva v SlovenijiAlex Mavrič, Štefan Bojnec, Andreja Ramšak, 2021, scientific monograph Abstract: Raziskava prinaša nova spoznanja in izzive s področij ribištva v Sloveniji in z njim povezanih panog. Z intervjuji smo pridobili primarne podatke za raziskovanje, ki je vključevalo različne vidike in segmente ribiškega trga v Sloveniji, s poudarkom na socio-ekonomskih dejavnikih. Preučevali smo ribolov in vzrejo školjk ter rib v morju in v celinskih vodah, povezovanje ribištva s turizmom, predelavo ribiških izdelkov, zlorabe na ribiškem trgu in sorodne teme kakortudi možnosti za trajnostni razvoj ribištva v slovenskem morju in v celinskih vodah. Rezultati intervjujev so nam dali vpogled v vrsto težav in v možne rešitve, kot so jih predvideli različni deležniki, povezani s trgom rib. V zaključku raziskave so predstavljeni ugotovitve o trgu rib, možne smeri in vplivi na razvoj trga rib. Glede na ugotovljene težave smo podali tudi predloge, ki bi lahko izboljšali stanje v ribištvu in na trgu rib v Sloveniji. Raziskava je prinesla nekaj pomembnih ugotovitev, kot so: slovenski potrošniki pojedo mnogo manj rib v primerjavi z ostalimi članicami Evropske unije, slabo so ozaveščeni o ribolovnih izdelkih in ozaveščanje je preveč kratkoročno usmerjeno, da bi dosegli spremembe. V vseh dejavnostih, povezanih s trgom rib, je potrebno zmanjšati vplive na okolje, kar bo pomagalo ohranjati ribolovne vire v naravnih vodah. Keywords: prehranska varnost, ribolov, ribogojstvo, akvakultura, trajnostni razvoj, zakonodaja, kvaliteta, trženje, razvojne perspektive, elektronske knjige Published in DiRROS: 08.08.2024; Views: 287; Downloads: 229 Full text (1,64 MB) This document has many files! More... |
635. Thermal lensing and photoacoustics as potential tools for nanomaterial characterization : a reviewMohanachandran Nair Sindhu Swapna, S. Sreejyothi, Dorota Korte, 2024, review article Abstract: This comprehensive review highlights the versatile applications of photothermal techniques, particularly thermal lens spectrometry (TLS) and photoacoustic spectrometry (PAS), in the field of nanomaterials characterization. TLS is an effective technique in the trace detection of different compounds in liquid samples, photodegradation studies, and analysis of photocatalytic reaction rate, as well as the study of molecular dynamics, impacting both environmental and catalytical research. It enables the optimization of thermal diffusivity in soot nanofluids and offers insights into seed germination and plant yield enhancement in nanobiophotonics. The review also explores the thermal and elastic characterization of Fe2O3 polymorphs by photoacoustic spectroscopy (PAS). Investigating the metal mirror demonstrates PAS’s efficacy in determining its reflection coefficient and thermal diffusivity. ZnO nanoparticles’ strong absorption on diatomite surfaces is revealed through PAS, emphasizing their effectiveness in light absorption enhancement. Furthermore, PA techniques address working frequency limitations in studying silicon-based nanomaterials. Thus, thermal lens and photoacoustic spectroscopy assume pivotal roles in unveiling the nuanced attributes of various nanostructured materials, thereby propelling advancements in the realms of science and technology. Keywords: material characterization, thermal lens spectrometry, photoacoustic spectrometry Published in DiRROS: 07.08.2024; Views: 333; Downloads: 271 Full text (4,59 MB) This document has many files! More... |
636. Hazard characterization of Alternaria toxins to identify data gaps and improve risk assessment for human healthHenriqueta Louro, Ariane Vettorazzi, Adela López de Cerain, Bojana Žegura, Matjaž Novak, 2024, review article Abstract: Fungi of the genus Alternaria are ubiquitous plant pathogens and saprophytes which are able to grow under varying temperature and moisture conditions as well as on a large range of substrates. A spectrum of structurally diverse secondary metabolites with toxic potential has been identified, but occurrence and relative proportion of the different metabolites in complex mixtures depend on strain, substrate, and growth conditions. This review compiles the available knowledge on hazard identification and characterization of Alternaria toxins. Alternariol (AOH), its monomethylether AME and the perylene quinones altertoxin I (ATX-I), ATX-II, ATX-III, alterperylenol (ALP), and stemphyltoxin III (STTX-III) showed in vitro genotoxic and mutagenic properties. Of all identified Alternaria toxins, the epoxide-bearing analogs ATX-II, ATX-III, and STTX-III show the highest cytotoxic, genotoxic, and mutagenic potential in vitro. Under hormone-sensitive conditions, AOH and AME act as moderate xenoestrogens, but in silico modeling predicts further Alternaria toxins as potential estrogenic factors. Recent studies indicate also an immunosuppressive role of AOH and ATX-II; however, no data are available for the majority of Alternaria toxins. Overall, hazard characterization of Alternaria toxins focused, so far, primarily on the commercially available dibenzo-α-pyrones AOH and AME and tenuazonic acid (TeA). Limited data sets are available for altersetin (ALS), altenuene (ALT), and tentoxin (TEN). The occurrence and toxicological relevance of perylene quinone-based Alternaria toxins still remain to be fully elucidated. We identified data gaps on hazard identification and characterization crucial to improve risk assessment of Alternaria mycotoxins for consumers and occupationally exposed workers. Keywords: mycotoxin, exposure routes, genotoxicity, endocrine disruption, immunosuppression, biotransformation, toxicokinetics, tenuazonic acid, alternariol, altenuene, tentoxin, altertoxin Published in DiRROS: 07.08.2024; Views: 285; Downloads: 236 Full text (3,22 MB) This document has many files! More... |
637. Groundwater is a hidden global keystone ecosystemMattia Saccò, Stefano Mammola, Florian Altermatt, Roman Alther, Rossano Bolpagni, Anton Brancelj, David Brankovits, Cene Fišer, Vasilis Gerovasileiou, Špela Borko, Maja Zagmajster, 2024, review article Abstract: Groundwater is a vital ecosystem of the global water cycle, hosting unique biodiversity and providing essential services to societies. Despite being the largest unfrozen freshwater resource, in a period of depletion by extraction and pollution, groundwater environments have been repeatedly overlooked in global biodiversity conservation agendas. Disregarding the importance of groundwater as an ecosystem ignores its critical role in preserving surface biomes. To foster timely global conservation of groundwater, we propose elevating the concept of keystone species into the realm of ecosystems, claiming groundwater as a keystone ecosystem that influences the integrity of many dependent ecosystems. Our global analysis shows that over half of land surface areas (52.6%) has a medium-to-high interaction with groundwater, reaching up to 74.9% when deserts and high mountains are excluded. We postulate that the intrinsic transboundary features of groundwater are critical for shifting perspectives towards more holistic approaches in aquatic ecology and beyond. Furthermore, we propose eight key themes to develop a science-policy integrated groundwater conservation agenda. Given ecosystems above and below the ground intersect at many levels, considering groundwater as an essential component of planetary health is pivotal to reduce biodiversity loss and buffer against climate change. Keywords: groundwater, keystone ecosystem, surface-subterranean connectivity Published in DiRROS: 07.08.2024; Views: 304; Downloads: 261 Full text (8,83 MB) This document has many files! More... |
638. Synthesis, purification, and cell-toxicity of a choline betainateLucija Jurko, Gregor Hostnik, Tobias Alexander Steindorfer, Alja Štern, Perica Bošković, Matej Bračič, Bojana Žegura, Rupert Kargl, 2024, original scientific article Abstract: In this work, choline chloride and betaine hydrochloride were condensed into a - to our knowledge - unreported choline betainate (N,N,N-trimethyl-2-oxo-2-(2-(trimethylammonio)ethoxy)ethanaminium chloride) using 1,1′-carbonyldiimidazole (CDI) activation of betaine hydrochloride in dimethylsulfoxide. The product and reaction intermediates were isolated, purified by preparative HPLC and analyzed in detail by infrared and nuclear magnetic resonance spectroscopy. The final product has a high cytotoxicity for L929 mouse fibroblasts, and low antibacterial activity against P. Aeruginosa and S. Aureus at concentrations of up to 20 mg/ml. It could potentially further be investigated for similar uses as suxamethonium chloride, a muscle relaxant drug. Keywords: choline chloride, betaine hydrochloride, carbonyldiimidazole, HPLC, antimicrobial, cytotoxicity Published in DiRROS: 07.08.2024; Views: 300; Downloads: 336 Full text (3,60 MB) This document has many files! More... |
639. In-depth comparison of adeno-associated virus containing fractions after CsCl ultracentrifugation gradient separationMojca Janc, Kaja Zevnik, Ana Dolinar, Tjaša Jakomin, Maja Štalekar, Katarina Bačnik, Denis Kutnjak, Magda Tušek-Žnidarič, Lorena Zentilin, Dmitri G. Fedorov, David Dobnik, 2024, original scientific article Abstract: Recombinant adeno-associated viruses (rAAVs) play a pivotal role in the treatment of genetic diseases. However, current production and purification processes yield AAV-based preparations that often contain unwanted empty, partially filled or damaged viral particles and impurities, including residual host cell DNA and proteins, plasmid DNA, and viral aggregates. To precisely understand the composition of AAV preparations, we systematically compared four different single-stranded AAV (ssAAV) and self-complementary (scAAV) fractions extracted from the CsCl ultracentrifugation gradient using established methods (transduction efficiency, analytical ultracentrifugation (AUC), quantitative and digital droplet PCR (qPCR and ddPCR), transmission electron microscopy (TEM) and enzyme-linked immunosorbent assay (ELISA)) alongside newer techniques (multiplex ddPCR, multi-angle light-scattering coupled to size-exclusion chromatography (SEC-MALS), multi-angle dynamic light scattering (MADLS), and high-throughput sequencing (HTS)). Suboptimal particle separation within the fractions resulted in unexpectedly similar infectivity levels. No single technique could simultaneously provide comprehensive insights in the presence of both bioactive particles and contaminants. Notably, multiplex ddPCR revealed distinct vector genome fragmentation patterns, differing between ssAAV and scAAV. This highlights the urgent need for innovative analytical and production approaches to optimize AAV vector production and enhance therapeutic outcomes. Keywords: recombinant adeno-associated viruses (rAAVs), CsCl ultracentrifugation gradient, analytical methods, digital droplet PCR (ddPCR), transmission electron microscopy (TEM), analytical ultracentrifugation (AUC), size-exclusion chromatography coupled with multi-angle light scattering (SEC-MALS), Illumina sequencing, virology Published in DiRROS: 07.08.2024; Views: 348; Downloads: 301 Full text (8,47 MB) This document has many files! More... |
640. Oxytetracycline hyper-production through targeted genome reduction of Streptomyces rimosusAlen Pšeničnik, Lucija Slemc, Martina Avbelj, Miha Tome, Martin Šala, Paul R. Herron, Maksym Shmatkov, Marko Petek, Špela Baebler, Peter Mrak, Daslav Hranueli, Antonio Starcevic, Iain S. Hunter, Hrvoje Petković, 2024, original scientific article Abstract: Most biosynthetic gene clusters (BGC) encoding the synthesis of important microbial secondary metabolites, such as antibiotics, are either silent or poorly expressed; therefore, to ensure a strong pipeline of novel antibiotics, there is a need to develop rapid and efficient strain development approaches. This study uses comparative genome analysis to instruct rational strain improvement, using Streptomyces rimosus, the producer of the important antibiotic oxytetracycline (OTC) as a model system. Sequencing of the genomes of two industrial strains M4018 and R6-500, developed independently from a common ancestor, identified large DNA rearrangements located at the chromosome end. We evaluated the effect of these genome deletions on the parental S. rimosus Type Strain (ATCC 10970) genome where introduction of a 145 kb deletion close to the OTC BGC in the Type Strain resulted in massive OTC overproduction, achieving titers that were equivalent to M4018 and R6-500. Transcriptome data supported the hypothesis that the reason for such an increase in OTC biosynthesis was due to enhanced transcription of the OTC BGC and not due to enhanced substrate supply. We also observed changes in the expression of other cryptic BGCs; some metabolites, undetectable in ATCC 10970, were now produced at high titers. This study demonstrated for the first time that the main force behind BGC overexpression is genome rearrangement. This new approach demonstrates great potential to activate cryptic gene clusters of yet unexplored natural products of medical and industrial value.
Keywords: genome reduction, antibiotic biosynthesis, oxytetracycline, cryptic metabolites Published in DiRROS: 07.08.2024; Views: 285; Downloads: 232 Full text (5,08 MB) This document has many files! More... |