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The use of magnetically modified microplastics in environmental studies
No full textV vsakdanjem življenju se srečujemo z vse večjo porabo plastike, ki je pogosto neustrezno odvržena v okolje. Ko je plastika izpostavljena okoljskim dejavnikom, razpade na manjše fragmente, imenovane mikroplastika. Velikost delcev mikroplastike in njena razširjenost v vseh vrstah ekosistemov predstavljata tveganja zaradi vpliva na organizme, hkrati pa tudi izziv pri monitoringu delcev. Posledično se v zadnjih letih povečuje število raziskav na tem področju, ki so osredotočene predvsem na proučevanje ekotoksikoloških vplivov, adsorpcijskih lastnosti ter procesov staranja in obnašanja delcev v okolju. V ta namen je treba pripraviti okoljsko relavantno mikroplastiko, ki jo proizvajamo z različnimi metodami fragmentacije ali z načrtovano polimerizacijo. Vedno bolj se za raziskave uporablja modificirana mikroplastika, ki jo na podlagi dodanih lastnosti lažje lociramo, ji sledimo in separiramo iz različnih raziskovanih sistemov in s tem potencialno poenostavimo laboratorijske poskuse. Opravljenih je bilo že nekaj raziskav z mikroplastiko, ki je bila modificirana s kovinami, fluorescentnimi barvili in magnetnimi delci. V tem delu smo raziskovali uporabnost modificirane magnetne mikroplastike. Uporabili smo štiri različne vrste mikroplastike (polietilen, polipropilen, polietilen tereftalat in polivinil klorid), na katere so bili nanešeni nanodelci železovega oksida. S testi strupenosti smo ugotovili, da tako nemodificirani kot tudi magnetno modificirani delci mikroplastike nimajo vpliva na malo vodno lečo Lemna minor. Testiranje izluževanja železa je pokazalo, da so koncentracije izluženega železa v mediju z nevtralnem pH zanemarljive, s čimer je bila potrjena stabilnost modificirane magnetne mikroplastike. V nadaljevanju smo preverili učinkovitost separacije omenjenih delcev iz vode, sedimentov dveh različnih velikosti in iz prsti z dvema različnima vlažnostma. Metoda separacije z magnetom se je izkazala za učinkovito pri ločevanju delcev iz vode in sedimenta (izkoristek nad 90 %), medtem ko je bil izkoristek separacije iz prsti bistveno nižji (okoli 10 %).In everyday life, we are faced with an increasing consumption of plastics, which often end up improperly disposed in the environment. When plastic is exposed to various environmental factors, it degrades into smaller fragments, known as microplastics. The widespread presence of microplastics in all types of ecosystems and the small size of the particles pose risks due to their impact on organisms and pose a challenge in particle monitoring. As a result, the number of studies in this field has also increased, focused on ecotoxicological impacts, adsorption properties, and the processes of aging and behaviour of particles in the environment. For this purpose, it is necessary to prepare environmentally relevant microplastics, which are produced with different fragmentation methods or with controlled polymerisation. Modified microplastics are increasingly being used in research, as their added properties make it easier to locate, track, and separate them from various studied systems, thereby potentially simplifying laboratory experiments. Several studies have already been conducted with microplastics doped with metals, fluorescent dyes, or magnetic particles. In this work, we focused on investigating the effects and potential applications of the latter. We used four different types of microplastics (polyethylene, polypropylene, polyvinyl chloride, and polyethylene terephthalate) coated with iron oxide nanoparticles. Toxicity tests showed that both unmodified and magnetically modified microplastics had no impact on Lemna minor (duckweed). Testing of iron leaching demonstrated that concentrations of leached iron in medium with neutral pH were negligible, confirming the stability of magnetic microplastics. We further examined the efficiency of separating these particles from water, sediments of two different grain sizes, and soils with two different moisture levels. Magnetic separation showed to be effective for removing particles from water and sediment (with recovery above 90 %), whereas the recovery of separation from soils was around 10 %
Methodological approach to multi-objective optimization of electrical machines with a practical case study
No full textTargeting G-rich lncRNA and its structural polymorphism with selective G-quadruplex ligands
No full textLong noncoding RNAs (lncRNAs) play essential regulatory roles, often mediated by complex structural elements such as RNA G-quadruplexes (rGQs). While ligand interactions with DNA G-quadruplexes (dGQs) have been extensively studied, for rGQs remain less explored. Here, we studied the SL15P RNA oligonucleotide derived from the REG1CP lncRNA, which adopts a parallel rGQ structure in equilibrium with a hairpin (Hp). A set of 12 small molecules, previously known for their ability to make complex with dGQs, was tested for their ability to bind and stabilize the SL15P rGQ. Using NMR spectroscopy, we analyzed complex formation and assessed whether these ligands could promote rGQ folding under conditions where the Hp structure is favored. Melting experiments with circular dichroism (CD) quantified the thermal stabilization induced by ligand binding. Our results show that ligands known to target dGQs exhibit different behaviors toward rGQs. Among the tested compounds, 360A, PhenDC3, and PDS proved to be the most effective, as they induced well-defined complex formation and significant stabilization of the SL15P rGQ. PhenDC3 showed evidence of a dual binding interaction. This study emphasizes that the binding of ligands to rGQs can be highly variable and supports the rational design of selective compounds for therapeutic purposes
Streaming on demand: the impact of platformization on listening habits of students
No full textMagistrsko delo je kvalitativna raziskava o vplivu platformizacije glasbene industrije na
poslušalske navade študentov. Analizira spremembe, ki jih pretočne storitve prinašajo v
kontekstu dostopa do glasbe, osebnih preferenc in algoritmičnih priporočil. Namen raziskave
je proučiti pogostost in intenzivnost uporabe pretočnih storitev, njihov vpliv na odkrivanje
nove glasbe, razlike med poslušanjem ročno in algoritmično ustvarjenih seznamov
predvajanja ter uporabnikovo zadovoljstvo z njimi. V raziskovalnem delu sta uporabljeni
metodi medijskih dnevnikov in fokusnih skupin. Ugotovitve razkrivajo, da se razlike v
uporabi pretočnih storitev kažejo glede na rutine, razpoloženje, osebne preference in družbene
okoliščine. Novo glasbo udeleženci pogosto odkrivajo prek algoritmov, vendar jim ne zaupajo
povsem, zato jih dopolnjujejo z lastno iniciativo in priporočili okolice. Udeleženci ne izbirajo
strogo med ročno in algoritmično ustvarjenimi seznami predvajanja, njuna raba je bolj
podobna dialogu. Večjo čustveno povezanost in s tem tudi večje zadovoljstvo izražajo do
ročno ustvarjenih seznamov predvajanja, medtem ko algoritme doživljajo predvsem kot
priporočila. Raziskava predstavlja prispevek k razumevanju razmerij med tehnologijo, kulturo
in sodobnimi načini konzumacije glasbe.This master\u27s thesis is a qualitative study on the impact of the platformization of the music
industry on students’ listening habits. It analyses the changes brought about by streaming
services in terms of access to music, personal preferences, and algorithmic recommendations.
The purpose of the research is to explore the frequency and intensity of streaming services
use, their influence on music discovery, the differences between listening to manually curated
and algorithmically generated playlists, and users’ satisfaction with them. The study employs
the methods of media diaries and focus groups. The findings reveal that differences in the use
of streaming services are shaped by routines, moods, personal preferences, and social
circumstances. Participants often discover new music through algorithms, but do not fully
trust them, complementing algorithmic suggestions with their own initiative and
recommendations from others. Participants do not strictly choose between manually created
and algorithmically generated playlistsrather, their use reflects a kind of dialog between the
two. Participants express a stronger emotional connection and consequently satisfaction with
manually created playlists, while they perceive algorithms as tools for recommendations. This
research contributes to a deeper understanding of the relationship between technology, culture
and contemporary ways of music consumption
Green infrastructure network concept on the example of Jugovzhodna Slovenija development region
No full textZelena infrastruktura je strateško zasnovano in povezano omrežje naravnih in polnaravnih območji, ki z zagotavljanjem ekosistemskih storitev predstavlja večnamensko in vzdržno rešitev za večanje podnebne odpornosti s številnimi pozitivnimi vplivi na počutje in zdravje ljudi. Aktualnost tematike se izkazuje prek neposrednih učinkov podnebnih sprememb v obliki ekstremnih vremenskih pojavov, ki kažejo na nujnost razvoja rešitev za njihovo blažitev. V duhu leta 2023 sprejete Resolucije o Strategiji prostorskega razvoja Slovenije 2050, ki zeleno infrastrukturo izpostavlja kot enega izmed štirih elementov prostorskega razvoja Slovenije in začetka priprave regionalnih prostorskih planov v nalogi opredelimo elemente zelene infrastrukture na regionalni ravni, ki jih lahko obravnavamo v okviru razvojnih regij v Sloveniji. Na primeru razvojne regije Jugovzhodna Slovenija elemente zelene infrastrukture konkretno opredelimo v prostoru, predlagamo koncept zasnove zelene infrastrukture razvojne regije Jugovzhodna Slovenija ter v sklepnem delu podamo usmeritve za pripravo zasnove omrežja zelene infrastrukture na regionalni ravni v okviru regionalnega prostorskega plana. Prepoznava obstoječe zelene infrastrukture na regionalni ravni je eden ključnih korakov upravljanja in planiranja prostora, saj zagotavlja temelj za razvoj funkcionalnega omrežja zelene infrastrukture s kar največjim izkoristkom potencialnih blagodejnih učinkov na ljudi in okolje. Naloga je uporabna kot priporočilo za prepoznavo elementov zelene infrastrukture na regionalni ravni in kot podlaga za pripravo vsebine regionalnega prostorskega plana v okviru priprave zasnove zelenega sistema regije.Green infrastructure is a strategically designed network of natural and semi-natural areas providing ecosystem services, promoting climate resilience, and enhancing human well-being. The importance of this topic is underscored by the direct effects of climate change, such as extreme weather events, necessitating effective mitigation solutions. In line with the 2023 Resolution on the Spatial Development Strategy of Slovenia 2050, which highlights green infrastructure as a key element of spatial development, and the initiation of regional spatial plans, this thesis defines regional green infrastructure elements within Slovenia\u27s development regions. Using the Jugovzhodna Slovenija development region as a case study, the thesis specifically defines green infrastructure elements, proposes a design concept for the region, and offers guidelines for creating a regional green infrastructure network within the regional spatial plan. Identifying existing green infrastructure at the regional level is crucial for spatial management and planning, providing a foundation for developing a functional green infrastructure network that maximizes benefits for people and the environment. Thesis serves as a recommendation for identifying green infrastructure elements at the regional level and as a basis for preparing regional spatial plans to design green infrastructure network within the region\u27s green system
From Li Zehou to Kant and back, or the precarious relation between apriorism and empiricism
No full textWe may describe Li Zehou and Henry Rosemont as examples of philoso- phers whose not just “compare.” Yet, there is a specific sense in which Li ‘s texts may still appear as “Chinese philosophy” and Rosemont’s as “American.” This causes difficulties which Jana Rošker’s paper meditates on. The thinkers discussed in this volume might be “beyond comparison,” but distinctive cultural elements remain. Many “comparative” interpretations of Li Zehou, Rošker argues, are methodologi- cally Western, but are still informed by traditional Chinese ideas. Specifically, she describes how Li Zehou interacts with Kant. Li’s work as a “process of transforming the empirical into the transcendental can be seen as a kind of synthesis of empiri- cism and rationalism.” This is, of course, problematic. Rošker summarizes: “Kant’s system is completely incompatible with Li Zehou’s philosophy.” However, the latter still engages productively with the former through what Rošker calls the process of “the sublation of philosophy.” If we respect differences and understand comparisons in this way, we better understand both Li’s thought and comparative philosophy
Development of piezoelectric nanofibers from polyhydroxybutyrate and poly-L-lactic acid for the accelerated healing of chronic wounds
No full textKronične rane so poškodbe kože in podkožnega tkiva, ki se kljub ustreznemu zdravljenju ne zacelijo v pričakovanem časovnem okviru in se pogosto ponavljajo. Z namenom izboljšanja kakovosti življenja obolelih oseb obstaja vse večja potreba po inovativnih terapevtskih rešitvah, ki bi spodbudile učinkovitejšo regeneracijo tkiva. Eden izmed obetavnih pristopov temelji na uporabi biokompatibilnih piezoelektričnih materialov, ki ob mehanskem dražljaju ustvarjajo električno napetost ter omogočajo lokalno elektrostimulacijo brez zunanjih elektrod, s čimer spodbudijo naravne procese celjenja.
Namen magistrske naloge je bil razviti napreden, popolnoma organski piezoelektrični material na osnovi poli-L-mlečne kisline (PLLA) v obliki nanovlaken, ki bi služil kot funkcionalna obloga z dvojno funkcijo: elektrostimulacijo poškodovanega tkiva in spodbujanje regeneracije tkiva zaradi biomimetične strukture. Za povečanje piezoelektričnega odziva smo material modificirali z vključitvijo laktobacilov Lacticaseibacillus paracasei, ki naravno proizvajajo polihidroksibutirat (PHB) – kristalni biopolimer, ki lahko deluje kot nukleacijsko jedro med nastankom nanovlaken. Postopek izdelave nanovlaken smo optimizirali z uporabo metode načrtovanja eksperimentov.
V eksperimentalnem delu smo potrdili, da izolirane bakterije L. paracasei proizvajajo PHB, kar smo dokazali s fluorescenčnim barvanjem, spektrofotometrično kvantifikacijo in analizo FTIR. Z gojenjem laktobacilov v stresnih pogojih smo dosegli statistično značilno povečano akumulacijo PHB. Kristalnost PHB po počasnem sušenju smo dokazali z rentgensko difrakcijo. Iz PLLA in bakterij smo uspešno izdelali orientirana nanovlakna, pri čemer so vzorci s stimuliranimi bakterijami izkazovali višji piezoelektrični signal kot nemodificirani ali kontrolni vzorci z nestimuliranimi bakterijami. Material je izkazal dobro biokompatibilnost, saj nanovlakna z vključenimi bakterijami niso negativno vplivala na preživetje človeških celic.
Rezultati dokazujejo, da je z vključitvijo stimuliranih bakterij s kristalnim PHB mogoče izboljšati piezoelektrične lastnosti materiala, ne da bi pri tem ogrozili njegovo biokompatibilnost. Razvita obloga tako predstavlja pomemben korak k razvoju biorazgradljivih, funkcionalno aktivnih piezoelektričnih biomaterialov, ki bi lahko bistveno prispevala k sodobnemu zdravljenju kroničnih ran.Chronic wounds are injuries to the skin and subcutaneous tissue that do not heal within the expected timeframe despite appropriate treatment and often tend to recur. To improve the quality of life of affected individuals, there is an increasing need for innovative therapeutic solutions that can enhance tissue regeneration. One promising strategy involves the use of biocompatible piezoelectric materials, which generate electrical voltage in response to mechanical stimulation and enable localized electrostimulation without the need for external electrodes, thereby activating natural healing processes.
The aim of this master’s thesis was to develop an advanced, fully organic piezoelectric material based on poly-L-lactic acid (PLLA) in the form of nanofibers, intended to serve as a functional wound dressing with dual functionality: electrostimulation of damaged tissue and promotion of regeneration due to its biomimetic structure. To enhance the piezoelectric response, the material was modified through the incorporation of Lacticaseibacillus paracasei, a lactic acid bacterium that naturally produces polyhydroxybutyrate (PHB), a crystalline biopolymer capable of acting as a nucleation site during nanofiber formation.
In the experimental part, we confirmed PHB production by isolated L. paracasei using fluorescent staining, spectrophotometric quantification, and FTIR analysis. Stress induction during bacterial cultivation led to a statistically significant increase in PHB accumulation. The crystallinity of PHB following slow drying was verified by X-ray diffraction analysis. Oriented nanofibers were successfully fabricated from PLLA and the bacteria, with samples containing stress-stimulated bacteria exhibiting a higher piezoelectric response compared to unmodified or control samples with non-stimulated bacteria. The material also showed good biocompatibility, as nanofibers with incorporated bacteria did not negatively affect the viability of human cells.
The results demonstrate that incorporating stress-stimulated bacteria with crystalline PHB can enhance the piezoelectric properties of the material without compromising its biocompatibility. Therefore, the developed dressing represents a significant step toward the creation of biodegradable, functionally active piezoelectric biomaterials that could contribute substantially to the modern treatment of chronic wounds
Positioning accuracy and error analysis in panoramic dental imaging
No full textUvod: Radiološke preiskave so pomemben vir pridobivanja informacij pri večini diagnostičnih postopkov. Razvoj panoramske radiografije je omogočil izboljšanje kakovosti slik, hkrati pa zmanjšal sevalno obremenitev za pacienta. Vendar pa tehnika zahteva natančno in pravilno namestitev predela slikanja, da se optimalno prikažejo potrebne strukture na sliki ter da se doseže diagnostična kakovost slike. Namen: Cilj magistrskega dela je bil oceniti uspešnost študentov radiološke tehnologije pri pravilni namestitvi fantoma glave za panoramsko slikanje zob ter njihove rezultate primerjati z izkušenimi radiološkimi inženirji s področja dentalne radiografije. Delo je bilo usmerjeno v ocenjevanje povezave med teoretičnim znanjem in praktično izvedbo ter v analizo najpogostejših napak pri namestitvi predela za panoramsko slikanje zob. Metode dela: Pridobivanje podatkov za magistrsko delo je potekalo v dveh delih. V prvem delu je šlo za pregled relevantne literature s preučevanega področja, drugi del pa je vključeval eksperimentalno metodo, kjer so sodelovali tako študenti radiološke tehnologije kot tudi zaposleni inženirji radiološke tehnologije s področja dentalne radiografije. V raziskavi je sodelovalo 51 študentov radiološke tehnologije in 10 zaposlenih radioloških inženirjev. Rezultati: V raziskavi smo po posameznih stopnjah izobrazbe ocenili vsak kriterij posebej. Skupno smo ugotovili, da so najmanj napak pri postavitvi fantoma naredili študentje 2. stopnje, nekoliko slabše so se odrezali študentje 1. stopnje, najslabše rezultate pa so prejeli zaposleni radiološki inženirji. Rezultatov te analize ne smemo posplošiti na celotno populacijo zaposlenih radioloških inženirjev, saj je v raziskavi sodeloval le sorazmeren delež le-teh, poleg tega pa je bilo tudi število študentov bistveno večje v primerjavi z zaposlenimi inženirji. Kriterij prekomerno posteriorne postavitve fantoma je vsem sodelujočim predstavljal največ težav, kriterij zvrnjenosti glave nazaj pa je predstavljal statistično značilno razliko med posameznimi skupinami. Razprava in zaključek: Ugotovili smo, da so razlike v kakovosti namestitve fantoma povezane predvsem z doslednostjo izvajanja postopkov in ne zgolj s kliničnimi izkušnjami. Pomembno je, da si izvajalci pri nameščanju predela slikanja vzamejo čas za natančno izvedbo, kajti s tem v kliničnem okolju ne prinašamo koristi le diagnostičnemu postopku, temveč tudi prispevamo k zmanjšanju ponovitev slikanj ter manjši izpostavljenosti ionizirajočemu sevanju.Introduction: Radiological examinations are an important source of information in most diagnostic procedures. The development of panoramic radiography has made it possible to improve image quality while at the same time reducing the radiation dose to the patient. However, the technique requires precise and correct positioning of the imaging region in order to optimally display the necessary structures in the image and achieve diagnostic image quality. Purpose: The aim of the master’s thesis was to assess the success of radiologic technology students in correctly positioning a head phantom for panoramic dental imaging and to compare their results with those of experienced radiologic engineers in the field of dental radiography. The thesis focused on evaluating the relationship between theoretical knowledge and practical performance, as well as analyzing the most common errors in positioning the region for panoramic dental imaging. Methods: Data collection for the master\u27s thesis was carried out in two parts. The first part consisted of a review of relevant literature in the studied field, while the second part involved an experimental method, which included the participation of both radiologic technology students and employed radiologic technologists in the field of dental radiography. The study included 51 radiologic technology students and 10 employed radiologic technologists. Results: In the study, we evaluated each criterion separately according to the level of education. Overall, we found that second-cycle students made the fewest mistakes in phantom positioning, first-cycle students performed somewhat worse, while the employed radiologic technologists received the poorest results. The results of this analysis should not be generalized to the entire population of employed radiologic technologists, since only a proportional share of them participated in the study, and the number of students was also significantly higher compared to the employed technologists. The criterion of excessive posterior phantom positioning proved to be the most challenging for all participants, while the criterion of head tilt backwards showed a statistically significant difference between the individual groups. Discussion and conclusion: Differences in the quality of phantom positioning during panoramic imaging are primarily related to the consistency of procedure execution rather than solely to clinical experience. It is important that operators take sufficient time for accurate positioning of the imaging region. This contributes not only to improved diagnostic quality but also to a reduction in repeat examinations and lower exposure to X-ray radiation in the clinical setting
Kakovost svetovanja pacientom v spletnih lekarnah v Sloveniji : odgovori lekarn in točkovniki ocenjevanja vseh primerov
No full textPriloga je vezana na magistrsko delo Eve Kuhar pod mentorstvom doc. dr. Nejca Horvata: Kakovost svetovanja pacientom v spletnih lekarnah v Sloveniji.
Priloga vsebuje celotne, originalne odgovore lekarn na klinične primere, poslane po elektronski pošti, ter ocenjevalne obrazce z merili za vrednotenje vsebine, odzivnosti in oblike svetovanja farmacevtov. Vključene so tudi točkovne sheme, ki omogočajo transparentnost postopka vrednotenja in ponovljivost raziskave
Patriotism and "civic" friendship
No full textJohn Rawls je v Teoriji pravičnosti približno takole povezal moralno poljubnost in ne-zasluženost: če si ne morem lastiti zaslug za določeno svojo lastnost, potem tudi nisem (bolj kot drugi) moralno upravičen do koristi, ki izvirajo iz njenega imetja. Državljanstvo se tipično podeljuje na podlagi določil, ki so v zgornjem pomenu moralno poljubna, naj-pogosteje kraja rojstva oz. državljanstva staršev. In čeravno je torej državljanstvo (točno določene države) v zgornjem pomenu besede moralno nezasluženo, le redki teoretiki problematizirajo nacionalno zakonodajo in ukrepe oblasti, ki sistematično favorizirajo domačine pred tujci oz. lastne državljane pred državljani drugih držav. V pričujočem članku kritično obravnavam poskuse, da bi po zgledu prijateljstva, kjer pristranskost po splošnem mnenju ne le, da ni moralno problematična, temveč velja za prototip moral-no vzornega medčloveškega razmerja, tudi domoljubje utemeljili na vzajemni skrbi in spoštovanju med sodržavljani. Če lahko namreč prijateljstvo generira medsebojne obveznosti in moralne razloge za delovanje, čeprav je izbira prijateljev v osnovi moralno poljubna, zakaj ne bi tudi v domoljubu videli človeka, ki - vsaj v političnih skupnostih, urejenih po demokratičnih načelih - v nekem smislu prijateljuje z vsemi svojimi sodržavljani in ima zato določene obveznosti izključno ali vsaj prvenstveno do njih? Toda že po nekoliko temeljitejši analizi normativne podstati običajnega, medosebnega prijateljstva se tovrstno \u27državljansko prijateljstvo\u27 celo v moralno idealiziranih političnih tvorbah izkaže za potencialno nevarno teoretsko utvaro. Lahko si, skratka, oddahnemo, ne bo nam treba po vsej sili \u27prijateljevati\u27 z neznanci in političnimi eksoti.In his theory of justice, John Rawls connected moral arbitrariness and undeservedness roughly as follows: if I cannot take credit for a certain property of mine, then I am not (any more than anyone else) morally entitled to the benefits of possessing, and making use of, that trait. Citizenship is typically assigned based on features that are morally arbitrary in the above sense, most commonly the place of birth and/or one’s parents’ nationality. And yet, although citizenship (of a particular country) is morally undeserved in the above sense, only a few theorists question the national legislation and the social policies that systematically favour natives over foreigners. In this arti-cle, I critically examine attempts to base patriotism on mutual concern and respect, considered constitutive of personal friendships, where bias towards someone is not only morally unproblematic but hailed as morally exemplary. Indeed, if friendship can generate mutual moral obligations and moral reasons for action, even though friendships are typically formed in a morally arbitrary way, why not also see in a patriot a person who (at least within political communities governed by democratic rule) in some sense “befriends” all her fellow citizens and, as a result, owes certain obligations just or primarily to them? However, a more thorough inquiry into the normative basis of ordinary, interpersonal friendship reveals this kind of “civic friendship” as a misconceived and potentially dangerous theoretical fiction, even in morally idealized political formations. In short, we can relax, as Slovene citizens we will not need to “befriend” strangers and political foes after all