123903 research outputs found
Sort by
Invasive properties of patient-derived glioblastoma cells after reversible electroporation in vitro
No full textBackground. Electroporation-based therapies are being explored in glioblastoma (GB) treatment, as means of enhancing drug delivery or achieving nonthermal ablation. Yet, little is known about how sublethal exposure affects the invasive behaviour of GB tumour cells. Materials and methods. Five patient-derived GB cell lines were initially screened for intrinsic invasive potential, and two most invasive (NIB140 CORE and NIB216 CORE) were selected for further experiments with electroporation treatment. Cells in suspension were exposed to bursts of high-frequency biphasic electric pulses resulting in electric field strength of 1 kV/cm, which corresponded to conditions of reversible electroporation. Changes in cell invasion and gene regulation were assessed 24 hours after electroporation using transwell assay and RNA transcriptome analysis, respectively. Results. Reversible electroporation at 1.0 kV/cm enhanced invasion in a cell line-dependent manner. NIB140 CORE showed a consistent and pronounced increase, with a median of 3.74-fold (274%) higher number of invading cells compared to sham control. In contrast, NIB216 CORE exhibited only a modest increase in invasion (1.30-fold30%). Transcriptomic profiling identified modulation of genes linked to extracellular matrix organization and ion channel activity in NIB140 CORE, and cytoskeletal remodelling in NIB216 CORE, indicating the activation of invasion-related pathways. Conclusions. These findings highlight a potential risk of pro-invasive responses in GB cells. In tumour ablation with irreversible electroporation, this concern relates to cells in the peripheral zone that may experience only sublethal electric fields, while in electrochemotherapy, a similar risk may arise if permeabilized cells are not effectively eliminated due to insufficient local drug delivery. Nevertheless, the two tested cell lines responded differently, underscoring patientspecific heterogeneity and the need for validation in more physiologically relevant models
Future-proof production scheduling and control
No full textTraditional production scheduling and control are increasingly inadequate in light of the rapid evolution of manufacturing technology, the growing impact of unforeseen disruptions, and the generally increasing complexity of production. A framework for future-proof production scheduling and control is introduced to close this gap, providing a comprehensive overview of future requirements and the necessary technologies and approaches. Robust decision criteria are derived, explained and filled with major recent advances in production scheduling and control, digital twins, artificial intelligence, and knowledge formalisation. Emerging trends are discussed, and an outlook for future research and decision-making is derived
"Green on the Go"
No full textČlanek obravnava zeleno zavajanje (angl. greenwashing) v turističnem prometu ter njegove pravne, tržne in družbene posledice. Osredotoča se na primere iz letalskega in križarskega prometa, potovalnih paketov ter kolesarskega turizma, kjer podjetja uporabljajo okoljske trditve brez ustreznih dokazov in tako zavajajo potrošnike. Analiziran je evropski in slovenski pravni okvir, ki postopoma zaostruje oziroma prepoveduje nejasne ali zavajajoče okoljske navedbe. Osrednji del članka je namenjen turističnemu transportu, kjer je zeleno zavajanje najpogostejše – zlasti v letalstvu, križarjenju in potovalnih paketih. Opisani so primeri podjetij, kot sta KLM in Ryanair, ki z oglaševanjem »trajnostnih goriv« ali »ogljične nevtralnosti« zavajajo potrošnike. Predstavljeni so tudi sodni postopki in odzivi EU institucij. Namen članka je ozaveščanje povprečnega potrošnika in opozorilo turističnim subjektom, ki uporabljajo te prakse. Avtorica poziva k večji transparentnosti in prevzemanju odgovornosti v oglaševanju trajnostnih potovanj.The article examines greenwashing in the tourism industry and its legal, marketing, and social implications. It focuses on examples from air and cruise transport, travel packages, and cycling tourism, where companies use environmental claims without adequate evidence, thereby misleading consumers. The paper analyses the European and Slovenian legal frameworks, which are gradually tightening or prohibiting vague and deceptive environmental statements. The central part of the article is devoted to tourism transport, where greenwashing is most common – particularly in aviation, cruise travel, and package tours. It describes cases of companies such as KLM and Ryanair, which mislead consumers through advertising “sustainable fuels” or “carbon neutrality.” The article also presents court proceedings and the reactions of EU institutions. It is written both to raise awareness among average consumers and to warn tourism operators who engage in such practices, while calling for greater transparency and accountability in the advertising of sustainable travel
The theme of the Virgin Mary and the sinful soul in the Czech oral and literary tradition: contribution to the interdisciplinary study of west Slavic legend songs
No full textČlanek obravnava češko obdelavo teme Marije in grešne duše, ki je znana tudi v slovenski pesniški kulturi. Temelji na raziskavi ustnega izročila čeških sejmarskih oz. kramarskih pesmi, kot jih prikazuje gradivo brnske podružnice Etnološkega inštituta Češke akademije znanosti. Gradivo je bilo pridobljeno z zbiranjem ljudskih pesmi med tridesetimi in petdesetimi leti dvajsetega stoletja. Članek temelji na enotnosti literarne produkcije (sejmarske tiskovine) in recepcije (ustno izročilo). Je rezultat interdisciplinarnih raziskav: predstavlja (1) izdajo češke različice pesmi Byla cesta ušlapaná, ó Maria Bolestná (Bila je uhojena pot, o Marija Žalostna), ki se je prenašala skozi ustno in literarno izročilo sejmarskih tiskovin(2) njeno interdisciplinarno analizo z vidika jezikoslovja, literarne zgodovine, etnologije, etnomuzikologije in himnologije(3) umestitev pesmi v širši kontekst, tako domači češki kot srednjeevropsko-germanoslavistični, vključno s slovenskim. V razpravo ponuja model metodologije raziskovanja pesemske kulture, ki temelji na interdisciplinarnem sodelovanju in bi ga bilo mogoče uporabiti v slovanski komparativistiki.The article deals with the Czech treatment of the theme of Mary and the sinful soul, which is also known in Slovenian poetic culture. It is based on a study of the oral tradition of Czech broadside ballads, as presented in the materials of the Institute of Ethnology of the Czech Academy of Sciences in Brno. The materials were obtained by collecting folk songs between the 1930s and 1950s. The article is based on the unity of literary production (broadside ballads) and reception (oral tradition). It is the result of interdisciplinary research, and presents the following: (1) an edition of the Czech version of the poem Byla cesta ušlapaná, ó Maria Bolestná (“There was a beaten path, O Maria the Sorrowful”), which was transmitted through the oral and literary traditions of the printed broadside ballads(2) its in-terdisciplinary analysis from the perspectives of linguistics, literary history, ethnology, ethnomusicology and hymnologyand (3) its placement in a broader context, both Czech and Central European-Germano-Slavic, including Slovene. The discussion offers a model of a methodology for researching song culture based on interdisciplinary cooperation, which could be applied in Slavic comparativistic
Type-based computation of knowledge graph statistics
No full textWe propose a formal model of a knowledge graph (abbr. KG) that classifies the ground triples into sets that correspond to the triple types. The triple types are partially ordered by the sub-type relation. Consequently, the sets of ground triples that are the interpretations of triple types are partially ordered by the subsumption relation. The types of triple patterns restrict the sets of ground triples, which need to be addressed in the evaluation of triple patterns, to the interpretation of the types of triple patterns. Therefore, a schema graph of a KG should include all triple types that are likely to be determined as the types of triple patterns. The stored schema graph consists of the selected triple types that are stored in a KG and the complete schema graph includes all valid triple types of KG. We propose choosing the schema graph, which consists of the triple types from a strip around the stored schema graph, i.e., the triple types from the stored schema graph and some adjacent levels of triple types with respect to the sub-type relation. Given a selected schema graph, the statistics are updated for each ground triple t from a KG. First, we determine the set of triple types stt from the schema graph that are affected by adding a triple t to an RDF store. Finally, the statistics of triple types from the set stt are updated
Sodobni izzivi implementacije in validacije računalniških sistemov v farmaciji 4.0
No full textThe validation of computerized systems in the pharmaceutical industry is increasingly complex due to the rapid advancement of digital technologies. Ensuring compliance with Good Manufacturing Practices (GMP), Good Laboratory Practices (GLP), and data integrity (DI) standards requires structured documentation and adherence to regulatory guidelines, such as GAMP 5. This study explores the leveraging method to optimize validation efforts, reduce redundant testing, and streamline compliance. It also examines the impact of modern technologies, including artificial intelligence (AI), machine learning (ML), blockchain, and cloud computing, on validation processes. The findings highlight both the challenges and opportunities these technologies present in enhancing efficiency, automation, and data security within Pharma 4.0. Ultimately, the research underscores the need for structured, traceable documentation and risk-based approaches to ensure regulatory compliance in an evolving digital landscape.Validacija računalniških sistemov v farmacevtski industriji je zapleten in zahteven proces predvsem zaradi naraščajoče kompleksnosti sistemov in strogih regulativnih zahtev. Zagotavljanje skladnosti z dobrimi proizvodnimi praksami (GMP), dobrimi laboratorijskimi praksami (GLP) in zahtevanimi visokimi standardi zagotavljanja integritete podatkov (DI) zahteva strukturiran in učinkovit pristop. Ta študija preučuje strategije za optimizacijo validacijskih procesov z metodo uporabe obstoječih preverjenih podatkov v skladu s smernicami GAMP 5. Poseben poudarek je namenjen ključni dokumentaciji, potrebni za implementacijo sodobnega računalniškega sistema. Poleg tega študija pri oblikovanju prihodnosti implementacije in validacije računalniških sistemov raziskuje vlogo nastajajočih modernih tehnologij, kot so umetna inteligenca (AI), strojno učenje (ML), veriženje blokov (blockchain) in računalništvo v oblaku. Čeprav te tehnologije prinašajo nove izzive, hkrati ponujajo pomembne priložnosti za izboljšanje učinkovitosti delovnih procesov, avtomatizacijo testiranja in povišano stopnjo regulatorne skladnosti. Ugotovitve poudarjajo prednosti strukturiranih validacijskih pristopov, ocenjevanja dobaviteljev in učinkovitega upravljanja dokumentacije pri poenostavljanju validacijskih postopkov brez ogrožanja zagotavljanja kakovosti. Študija izpostavlja potrebo po uravnoteženem pristopu, ki združuje inovacije in regulatorno skladnost, s čimer podpira preobrazbo farmacevtske industrije v dobi farmacije 4.0
Prispevek časovne informacije k izračunu možganske funkcijske konektivnosti pri oceni njene povezave z medosebnimi razlikami v vedenju
No full textFunctional connectivity (FC) refers to the statistical associations of time series between signals
from different brain regions. We investigated the role of temporal information in FC
computation for understanding brain-behavior associations and improving the generalizability
of such associations. Two aspects of temporal information in FC computation were
considered: sensitivity to the temporal order and variability of FC estimates over time. We
examined both aspects in two studies.
The first study compared FC methods that differ in their sensitivity to the temporal order
(static vs. dynamic) and the number of regions considered when estimating a single
edge (bivariate vs. multivariate). Similarities between FC matrices, node centrality measures,
and patterns of brain-behavior associations were assessed. Although FC estimates did not
differ as a function of sensitivity to temporal order, we observed differences between the
multivariate and bivariate FC methods. We conclude that dynamic FC estimates represent
information that is largely similar to that of static FC.
In the second study, we examined the between-subject and within-subject variability of
FC estimates. We hypothesized that brain features with higher between-subject variability
and lower within-subject variability would be more informative about brain-behavior associations
than other features. We showed that FC edges varying across subjects were primarily
located in associative networks, whereas FC edges varying across time were located in unimodal
networks. Resting-state FC was predominantly influenced by stable individual factors,
whereas time-scale variation was smaller and more subject-specific. We used canonical correlation
analysis to examine brain-behavior associations. Although models based on edges
with low within-subject and high between-subject variability performed similarly to models
based on all edges, edges with higher between-subject variability were generally more informative
than edges with lower between-subject variability.
Our research highlights the importance of carefully considering multiple factors throughout
the analysis pipeline when investigating brain-behavior associations.Funkcijska konektivnost (FC) se nanaša na statistične povezave časovnih vrst med signali iz različnih možganskih področij. Naš cilj je bil raziskati vlogo časovne informacije pri izračunu FC za razumevanje povezav med možgani in vedenjem ter izboljšanje posplošljivosti takšnih povezav. Upoštevali smo dva vidika časovnih informacij v FC: občutljivost na časovni vrstni red in spremenljivost ocen FC v času.
V prvi študiji smo primerjali metode FC, ki se razlikujejo po občutljivosti na časovni vrstni red (statične in dinamične) in po številu področij, upoštevanih pri oceni posamezne povezave (bivariatne in multivariatne). Ocenili smo podobnosti med matrikami FC, merami centralnosti vozlišč in vzorci povezav med možgani in vedenjem. Čeprav se ocene FC niso razlikovale v odvisnosti od občutljivosti na časovni vrstni red, smo opazili razlike med multivariatnimi in bivariatnimi metodami. Dinamična FC torej predstavlja informacije, ki so v veliki meri podobne statični FC.
V drugi študiji smo preučili medosebno in znotrajosebno variabilnost ocen FC. Predvidevali smo, da bodo povezave z večjo medosebno variabilnostjo in nizko znotrajosebno variabilnostjo bolj informativne z vidika povezav med možgani in vedenjem v primerjavi z ostalimi povezavami. Pokazali smo, da so se funkcijske povezave z večjo medosebno variabilnostjo
nahajale predvsem v asociativnih omrežjih, medtem ko so se povezave, ki so se spreminjale v času, nahajale v unimodalnih omrežjih. Na FC v stanju mirovanja so pretežno vplivali stabilni individualni dejavniki, medtem ko je bil vpliv dejavnikov, povezani s spremembami v času, manjši in bolj specifičen za posamezne udeležence. Za preučevanje povezav med možgani in vedenjem smo uporabili kanonično korelacijsko analizo. Čeprav so se modeli, ki temeljijo na povezavah z nizko znotrajosebno visoko medosebno variabilnostjo obnesli podobno kot modeli, ki temeljijo na vseh povezavah, so bile povezave z večjo medosebno variabilnostjo na splošno bolj informativne kot povezave z manjšo medosebno variabilnostjo.
Naša raziskava poudarja, kako pomembno je, da pri raziskovanju povezav med možgani in vedenjem skrbno upoštevamo več dejavnikov v celotnem postopku analize
Optimization of the Design and Fabrication of Antiresonant Hollow-Core Fibers for use in Ultrafast Lasers
No full textV magistrskem delu se ukvarjamo z zasnovo in proizvodnjo antiresonančnih vlaken z votlim jedrom za uporabo v ultrahitrih laserjih. Najprej se osredotočimo na optimizacijo zasnove, kjer z uporabo komercialnega orodja študiramo vpliv geometrije vlakna na prevajanje svetlobe. Ugotovimo, da je ključen parameter, ki ga je treba natančno nadzirati za zagotavljanje minimalnih izgub v vlaknu, debelina kapilar. V skladu s to ugotovitvijo nato proučujemo proces vlečenja antiresonančnih vlaken z votlim jedrom in ga optimiziramo tako, da lahko dosežemo želeno končno geometrijo, obenem pa zagotovimo čim manjše negotovosti v debelini kapilar. Simulacijo vlečenja kalibriramo s pomočjo testnih vlečenj.This thesis focuses on the design and fabrication of antiresonant hollow-core fibers for use in ultrafast lasers. Firstly, we focus on design optimization, where we use a commercial tool to study the impact of fiber geometry on light transmission. We find that the most crucial parameter for the minimization of losses in the fiber is the thickness of the capillaries. Following this finding, we then study the fiber drawing process for antiresonant hollow-core fibers and optimize it to achieve the desired final geometry while ensuring minimal uncertainties in the capillary thickness. The fiber drawing simulation is calibrated using test draws
Characterization of polystyrene-degrading bacteria isolated from plastic processing plants
No full textThis study investigated the occurrence of the most common types of bacteria and fungi on the surfaces of production lines, raw materials, and finished products in plastics processing plants. The total aerobic colony count was confirmed in 42.0% of the samples, followed by moulds (30.0%) and representatives of the genera Bacillus (28.3%) and Staphylococcus (19.9%). Growth on a solid medium with polystyrene was confirmed in 63 (63.4%) of the 96 selected strains, but only 3 (3.0%) of them were able to form a clear zone around the colonies. In addition, the ability of 10 selected bacterial strains to form biofilms and to degrade PS surfaces was determined. The highest weight loss of polystyrene was observed in the presence of Bacillus strains. Depending on the strain, the degradation rate was between 0.12 and 0.78% after 30 days and between 0.21 and 2.15% after 60 days. The number of living cells in biofilms on surfaces was lowest for the Gram-negative strains Burkholderia and Moraxella and highest for most Bacillus and some Micrococcus strains. Fourier transform infrared spectroscopy revealed differences in the ratios of vibrational bands after exposure to bacterial strains, although no oxygen-containing functional groups were observed on the surface of polystyrene samples. The average contact angle values of polystyrene surfaces exposed to the tested bacterial strains decreased from 80.55 ± 0.39° to 73.64 ± 0.45° after 60 days of incubation. Some isolated bacterial strains from plastic production plants show the potential for more intensive degradation of such materials, which could impact the quality and shelf life of plastic products
Development of electrical discharge machinable SiC-ZrN composites
No full textDense SiC-(10-30 vol%) ZrN composites were developed using spark plasma sintering with AlN-Y2O3 additives at 1800 °C for 5 min in nitrogen atmosphere. The nascent oxide present on ZrN surface reduces liquid phase formation temperature, facilitating improved densification of SiC ceramics. Mechanical properties were retained, and electrical conductivity increased with ZrN addition. To demonstrate a rapid and low-cost machining alternative for SiC ceramics, SiC-ZrN composites were successfully cut using wire-EDM. The tribological potential of novel electrical discharge machinable SiC-ZrN composite disk against SiC ball at various conditions of reciprocating sliding contacts was investigated. Friction is less affected by reinforcement content at room temperature (25 ℃) but significant change is observed at high temperature (600 ℃). Minimum one order of lower wear rate is reported with an increase in temperature from 25 ℃ to 600 ℃. The major wear mechanism changed from abrasion to tribo oxidation with increase in temperature