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Evaluation of biological response of NCTC-2544 keratinocytes to glass and rock wool fibres
No full textPri proizvodnji in delu s stekleno ali kameno volno se delavci pogosto srečujejo z neprijetnimi občutki na koži, kot je srbečica, ki se razvije, ko vlakna pridejo v stik s kožo. Čeprav gre za pogost pojav, mehanizmi, ki vodijo do takšnega kožnega draženja, še niso povsem raziskani. Ker mineralna vlakna ne povzročajo kemične iritacije, se domneva, da je srbenje posledica njihovega mehanskega delovanja. Najverjetneje ga povzročajo drobni delci vlaken, ki ob stiku z zgornjo plastjo kože fizično dražijo povrhnjico. Namen magistrske naloge je bil ugotoviti, ali lahko mineralna vlakna mehansko dražijo keratinocite, celice najbolj zunanje plasti kože, ki prve pridejo v stik z zunanjimi dejavniki.
V eksperimentalnem delu magistrske naloge smo ovrednotili vpliv izpostavljenosti različnih vrst mineralnih vlaken človeškim keratinocitom NCTC-2544. Vpliv mineralnih vlaken smo spremljali z različnimi metodami v koncentracijski in časovni odvisnosti. Vpliv vlaken na preživetje celic smo ocenili z metabolnim testom, morebitne poškodbe celične membrane smo določali s testom laktat dehidrogenaze, izražanje proteina akvaporin 3 smo analizirali z imunofluorescenčno detekcijo ter izražanje vnetnih dejavnikov s prenosom western. Spremembe v celični obliki in strukturi smo opazovali s svetlobnim invertnim mikroskopom, medtem ko nam je vrstična elektronska mikroskopija omogočila natančnejši vpogled v spremembe na celični površini.
Rezultati so pokazali, da mineralna vlakna vplivajo na metabolno aktivnost keratinocitov, povzročajo poškodbe celične membrane in spremembe v morfologiji celic. Učinki so bili izrazitejši pri višjih koncentracijah in daljši izpostavljenosti, kar se je pokazalo kot zmanjšana vitalnost celic, spremembe oblike, izguba stika s podlago ter povečana izraženost in spremenjena lokalizacija akvaporina 3. Vnetni odziv sicer ni bil vedno zaznan, a opažene spremembe kažejo na vpliv vlaken na celične funkcije.
Ti rezultati potrjujejo, da lahko stik z določenimi vrstami mineralnih vlaken vpliva na kožne celice in sproži odzive, ki so značilni za mehansko draženje. Raziskava prispeva k razumevanju vpliva fizikalnih lastnosti vlaken na kožne celice in je lahko v pomoč pri razvoju novih izdelkov.During the production and handling of glass or rock wool, workers often experience skin discomfort such as itching, which develops when the fibres come into contact with the skin. Although this is a common occurrence, the mechanisms leading to such skin irritation are not yet fully understood. Since mineral fibres do not cause chemical irritation, it is assumed that the itching results from their mechanical action. Most likely, it is caused by small fibre fragments that physically irritate the outermost layer of the skin. The aim of this Master\u27s thesis was to investigate whether mineral fibres can mechanically irritate keratinocytes, the cells that make up the majority of the outermost layer of the skin and are the first to come into contact with the environment.
In the experimental part of the thesis, we evaluated the effects of exposure to different types of mineral fibres on human keratinocytes NCTC-2544. The impact of mineral fibres was monitored using various methods in a concentration and time dependent manner. Cell viability was evaluated using a metabolic assay, while potential cell membrane damage was assessed using the lactate dehydrogenase release assay. Expression of the aquaporin 3 protein was analyzed using immunofluorescence detection, and the expression of inflammatory markers was assessed by western blotting. Changes in cell shape and structure were observed using light inverted microscopy, while scanning electron microscopy provided a more detailed view of changes on the cell surface.
The results showed that mineral fibres affect keratinocyte matebolic activity, cause cell membrane damage, and induce changes in cell morphology. The effects were more pronounced at higher concentractions and longer exposure times, manifested as decreased cell viability, altered cell shape, loss of adhesion, and increased expression and altered localization of aquaporin 3. While an inflammatory response was not always detected, the observed changes indicate an effect of the fibres on cellular functions.
These findings confirm that contact with certain types of mineral fibres can affect skin cells and trigger responses usually seen with mechanical irritation. The findings offer insight into how fibres interact with skin cells and may help guide the development of more user-friendly materials
The remains of the former Venetian border hidden in the cadastral municipality boundaries on the Kraški rob plateau around Črnotiče
No full textThe remains of the former Venetian border have been preserved in some places as boundary points of the cadastral municipalities. On the Kraški rob, Slovenia, special elongated piles of stones have been preserved, which are called muše by the locals. We measured 27 of them on the southern border of the cadastral municipality of Črnotiči. Two natural boundary points from the time of the Venetian Republic were identified: Brstenik spring and a small cave near a doline called V jami. Additionally, three carved limestone boundary stones from the time of the Franciscan land cadastral survey bearing the year 1819 and 21 boundary marks, mostly without inscriptions (two with the year 1865), located on or near the northeast border of the cadastral municipality of Črnotiči, are presented. Here, the Špirnica cave was also identified as a boundary point, at least since the time of the Franciscan land cadastral survey. At Krapnik, named on the Franciscan land cadastral map Rjavi kamen u štirni (Eng. brown stone in the well), a boundary stone of the three cadastral municipalities of Črnotiče, Podgorje, and Podpeč can be found. It is a larger, roughly hewn stone of a dark brown colour, with the year 1865 carved into it and the remains of fan-shaped lines on one side and a decaying circular shape on the other. It is located just 500 m north of the former corner point of the Venetian border on Debeli hrib, so it may even be an old Venetian boundary stone.Ostanki nekdanje beneške meje so se ponekod na terenu ohranili kot označevalci veljavnih mej katastrskih občin. Tako na Kraškem robu najdemo podolgovate kupe kamenja, ki jih domačini imenujejo muše. Na južnem robu katastrske občine Črnotiči smo jih izmerili 27. Na terenu smo identificirali še dve naravni mejni točki iz časa Beneške republike: izvir Brstenik ter brezno na zgornjem robu vrtače, imenovane V jami. Predstavili bomo še tri klesane apnenčaste mejnike iz časa franciscejske zemljiškokatastrske izmere z letnico 1819 ter 21 mejnikov srenj, večinoma brez napisov, ki so na severovzhodni meji katastrske občine Črnotiče ali v njeni bližini (dva z letnico 1865). Tu najdemo še jamo Špirnico, ki velja za mejnik te katastrske občine vsaj od časa franciscejske izmere naprej. Zelo zanimiv je še tromejnik katastrskih občin Črnotiče, Podgorje in Podpeč iz Krapnika na načrtu franciscejske izmere, imenovan Rjavi kamen v štirni. Mejnik predstavlja večji grobo klesan kamen temnejše rjave barve, na njem najdemo vklesano letnico 1865 ter pod njo ostanek pahljačastih črt, na drugi strani pa razpadajočo krožno obliko. Stoji le slabih 500 metrov severneje od nekdanje vogalne točke beneške meje na Debelem hribu, zato sklepamo, da bi to lahko bili ostanki beneškega in avstrijskega grba, torej bi to lahko bil nekdanji beneški mejnik
Stability evaluation of pantoprazole alkaline aqueous solution in different formulations
No full textPantoprazol je zdravilna učinkovina iz skupine zaviralcev protonske črpalke, ki selektivno in ireverzibilno inhibira protonsko črpalko v parietalnih celicah želodčne sluznice. S tem učinkovito znižuje izločanje klorovodikove kisline, ne glede na naravo dražljaja. Zaradi svoje kemijske zgradbe je pantoprazol občutljiv na svetlobo, kisik in kislo okolje, kar zahteva posebno pozornost pri formulaciji in shranjevanju. Stabilnost zdravilne učinkovine je eden ključnih kazalnikov kakovosti, saj neposredno vpliva na učinkovitost in varnost zdravila.
Cilj te magistrske naloge je bil kritično ovrednotiti stabilnost bazične vodne raztopine pantoprazola v kombinaciji z različnimi pomožnimi snovmi v farmacevtski obliki tekočine v ampuli za parenteralno uporabo, pripravljene za takojšnjo uporabo, z namenom kasnejše pridobitve dovoljenja za promet z zdravilom. Registracija novega zdravila je pogojena z izpolnjevanjem strogih regulatornih zahtev, ki zagotavljajo kakovost, varnost in učinkovitost zdravila, zato je potrebno posebno pozornost nameniti stabilnosti učinkovine ter prisotnosti razgradnih produktov.
Za pridobitev verodostojnih rezultatov smo najprej na osnovi farmakopejskih smernic validirali analitsko metodo za kvantitativno določevanje vsebnosti pantoprazola in spremljanje nastanka njegovih razgradnih produktov. Eksperimentalni del je vključeval preučevanje različnih formulacij pod različnimi pogoji shranjevanja ter izvajanje analiz, na podlagi katerih smo s pomočjo programske opreme ocenili kinetiko razgradnje in napovedali stabilnost v daljšem časovnem obdobju.
Rezultati stabilnosti so pokazali, da je kemijska stabilnost pantoprazola v preučevanih formulacijah nezadostna za dolgoročno shranjevanje. Modeliranje z uporabo programa ASAPprime je nakazalo, da bi po dveh letih shranjevanja prišlo do preseganja kvalifikacijskih mej nečistot, kar potrjuje visoko tveganje za stabilnost končnega zdravila.
Ugotovitve potrjujejo, da sta natančna izbira pomožnih snovi in zagotavljanje ustrezne zaščite pred kisikom, svetlobo ter predvsem kislim okoljem ključnega pomena za zagotavljanje ustrezne stabilnosti in s tem kakovosti končnega izdelka.Pantoprazole is an active pharmaceutical ingredient from the group of proton pump inhibitors, which selectively and irreversibly inhibits the proton pump in the parietal cells of the gastric mucosa. This effectively reduces the secretion of hydrochloric acid, regardless of the nature of the stimulus. Due to its chemical structure, pantoprazole is sensitive to light, oxygen, and acidic environments, which requires special attention in formulation and storage. The stability of the active ingredient is one of the key quality indicators, as it directly affects the activity and safety of the drug.
The aim of this master\u27s thesis was to critically evaluate the stability of a basic aqueous solution of pantoprazole in combination with various excipients, formulated as a ready-to-use liquid ampoule for parenteral administration, with the goal of obtaining marketing authorization for the drug. The registration of a new drug is subject to strict regulatory requirements that ensure the quality, safety, and activity of the drug. Therefore, particular attention must be paid to the stability of the active ingredient and the presence of degradation products.
To obtain reliable results, we an analytical method for the quantitative determination of pantoprazole content and monitoring of its degradation products was first validated in accordance with pharmacopeial guidelines. The experimental part included the investigation of various formulations under different storage conditions and the execution of analytical tests. Based on the results, degradation kinetics were assessed using specialized software, allowing for the prediction of long-term stability.
Stability studies revealed that the chemical stability of pantoprazole in the tested formulations was insufficient for long-term storage. Modeling with the ASAPprime software indicated that, after two years of storage, impurity qualification limits would be exceeded, confirming a high risk of instability in the final drug product.
These findings highlight that the careful selection of excipients and the provision of adequate protection from oxygen, light, and especially acidic conditions are crucial for ensuring the stability and overall quality of the final product
Long plane trees
No full textIn the longest plane spanning tree problem, we are given a finite planar point set , and our task is to find a plane (i.e., noncrossing) spanning tree for with maximum total Euclidean edge length. Despite more than two decades of research, it remains open whether this problem is NP-hard. Thus, previous results have focused on polynomial-time algorithms that produce plane trees whose total edge length approximates , the maximum possible length. The approximate trees in these algorithms all have small unweighted diameter, typically two to four. It is natural to ask whether this is a common feature of longest plane spanning trees, or an artifact of the specific approximation algorithms. We provide three results to elucidate the interplay between the approximation guarantee and the unweighted diameter of the approximate trees. First, we describe a polynomial-time algorithm to construct a plane tree with diameter at most four and total edge length at least . This constitutes a substantial improvement over the state of the art. Second, we show that a longest plane tree among those with diameter at most three can be found in polynomial time. Third, for any candidate diameter , we provide upper bounds on the approximation factor that can be achieved by a longest plane tree with diameter at most (compared to a longest plane tree without constraints)
Impact of fungal decay on the structural integrity of wood
No full textWood-destroying fungi induce different types of decay, which cause significant reductions in elastomechanical properties of wood when the mass loss is not yet gravimetrically detectable. Particularly difficult to define is incipient decay since the reduction of elastomechanical properties is highly dependent on the heterogeneity of wood species. Early-stage effects of incipient decay on impact behavior remain insufficiently understood. The aim of this study was to clarify how different rot types affect structural integrity in relation to mass loss. Therefore European beech (Fagus sylvatica) and Scots pine (Pinus sylvestris) sapwood specimens were incubated with white-rot (Trametes versicolor), brown-rot (Coniophora puteana) or soft-rot fungi. After incubation, moisture content and relative mass loss were measured. Mass loss (ML) increased linearly over time across all fungi-wood combinations, reaching a maximal reduction of 67% in European beech wood and 39% in Scots pine sapwood with Trametes versicolor. For Coniophora puteana, ML in European beech peaked at 26%, while Scots pine sapwood reached 24%. Soft-rot fungi caused the least degradation reaching 9% ML for European beech wood and 4% for Scots pine sapwood after 99 days. High-Energy Multiple Impact (HEMI) – tests were performed to evaluate the effect of mass loss by fungal decay on the structural integrity of wood, expressed as the Resistance to Impact Milling (RIM). The RIM decreased with increasing ML at early-stages proving the high sensitivity of the test to detect incipient decay, especially with brown rot. The reduction of structural integrity was compared with the reduction of different strength properties of wood depending on the mass loss, where RIM values exhibited less variability compared to other strength properties, suggesting higher measurement stability in case of white and brown-rot decay
Modeling the meaning of verbal probabilities
No full textIzrazi verjetnosti so besede ali besedne zveze, ki se namesto numeričnih vrednosti uporabljajo za izražanje verjetnosti dogodkov, npr. zagotovo, morda in nemogoče. S takimi izrazi se srečujemo vsakodnevno, pri čemer pa jih vsak razume nekoliko drugače. V prizadevanju za bolj zanesljivo razlago so številne stroke sprejele standardizirane slovarje in njihove numerične prevode. Ker pa ljudje intuitivno uporabljamo različne nabore izrazov in težko prezremo lastno interpretacijo, je standardizacija lahko problematična.
V magistrskem delu se osredotočimo na alternativno rešitev standardizaciji, kjer preučimo prevod slovarja verjetnostnih izrazov ene osebe v slovar druge osebe. Za modeliranje verjetnostnih izrazov uporabimo funkcije pripadnosti, pri čemer predstavimo novo metodo zajema z žetoni, ki jo primerjamo z uveljavljeno metodo zajema z drsniki. Poleg tega uvedemo novo mero podobnosti med funkcijami pripadnosti, ki za razliko od obstoječih pristopov upošteva celotno porazdelitev funkcije. Analiza podatkov, zbranih v okviru ankete, pokaže, da metoda z žetoni praviloma vodi do ožjih funkcij pripadnosti z izrazitejšimi vrhovi, kar je posebej uporabno pri prevajanju med slovarji. Nasprotno z dosedanjimi raziskavami ugotovimo, da prevod, ki temelji na vsebinsko enakih izrazih, doseže nižjo ceno kot prevod, ki upošteva zaporedje izrazov v slovarju.Verbal probabilities are phrases used instead of numerical values to describe the likelihood of events, such as certain, maybe, and impossible. We encounter them daily, yet each person interprets them somewhat differently. To achieve more consistent interpretations, many fields have adopted standardized lexicons and their numerical translations. However, standardization can be problematic because people naturally rely on their own lexicons and cannot easily disregard their personal interpretations.
In this thesis, we explore an alternative to standardization by examining how the probability lexicon of one individual can be translated into the lexicon of another. We model verbal probabilities using membership functions and introduce a new elicitation method, chips and bins, which we compare with the commonly used slider-based approach. We also propose a new similarity measure between membership functions that, unlike existing approaches, accounts for the entire distribution of the function. Analysis of data collected through an online survey shows that the chips and bins method generally produces membership functions with narrower breadth and more pronounced peaks, making them particularly useful for translating between lexicons. Contrary to related studies, we also find that translations based on identical phrases outperform translations based on equally ranked phrases
Evaluating the psychosocial impacts of e-care use among older people receiving long-term care in Slovenia through the adapted PIADS-10 scale
No full textPurpose: assistive technologies (ats), including e-care, are increasingly vital in supporting the ageing population’s long-term carehowever, there is a scarcity of studies analysing the psychosocial impacts of e-care use among older people. the goal of this paper is twofold: first, to understand the psychosocial impacts of e-care use among older people receiving long-term care, and second, to evaluate the measurement properties of an internationally recognised self-report questionnaire, the Psychosocial impact of assistive Devices scale (PiaDs-10), specifically its multidimensionality and internal consistency of identified subscales. Materials and methods: a one-group post-test-only quasi-experimental intervention design was employed. Psychosocial impacts of e-care use were examined through an intervention study involving 217 older people in Slovenia, who tested e-care over an average period of 310.2 days. Participants were selected using purposive sampling. Results: Findings revealed important enhancements in perceived security, sense of control, independence and overall quality of life among e-care users. exploratory factor analysis of the PiaDs-10 yielded two factors (psychological well-being and adaptability), supporting a reduced 8-item version (si-PiaDs-8), which was further supported through confirmatory factor analysis. Conclusions: these findings indicate that the PiaDs-10 could be refined to an 8-item, two-factor version with improved relevance for assessing psychosocial impacts among older adults using e-care. such insights can help stakeholders design and adapt ats that better support ageing in place