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DYNAMICS AND PROPERTIES OF ORGANIC MATTER IN THE CHANGING MARINE ENVIRONMENT OF ROGOZNICA LAKE – ZMAJEVO OKO (CROATIA)
No full textOrganski ugljik je važan indikator globalnih promjena te važna komponenta u biogeokemijskim procesima u morskom okolišu. Ovaj rad istražuje promjene u kvalitativnim i kvantitativnim svojstvima organske tvari (OT), kompleksne smjese organskih spojeva s različitim karakteristikama koje se mijenjaju pod utjecajem promjenjivih okolišnih uvjeta u jedinstvenom, raslojenom euksinskom morskom okruženju Rogozničkog jezera - Zmajeva oka (RJ) na istočnoj obali Jadranskog mora. RJ pruža brz odgovor na okolišne promjene, što ga čini idealnim za istraživanje brojnih biogeokemijskih procesa uzrokovanih tim promjenama. Primjetne promjene uključuju zagrijavanje vodenog stupca, deoksigenaciju, te akumulaciju toksičnih sulfida i amonijaka. Dugoročna analiza (1996. - 2020.) OT u RJ pokazuje specifičnu dinamiku OT, uključujući akumulaciju čestičnog organskog ugljika (POC, engl. particulate organic matter) u vodenom stupcu i otopljenog organskog ugljika (DOC, engl. dissolved organic matter) u anoksičnom pridnenom sloju. Potvrđene su kvantitativne i kvalitativne promjene OT sukladno elektrokemijskim mjerenima površinski aktivnih tvari (PAT), kao najreaktivnije skupine spojeva organskog ugljika. Elektrokemijska analiza, posebno parametar normalizirane površinske aktivnosti (NPA), pokazala se pouzdanim indikatorom promjena u DOC-u morskog okoliša. Načela karakterizacije OT ispitana su i u eutrofnim uzorcima (uzorci obogaćeni s DOC-om i POC-om do 320 mg L-1 i PAT-om do 15 mg L-1) s područja sjevernog i srednjeg Jadrana, dodatno i po prvi puta koristeći stabilne izotope δ13C, δ15N i δ34S, te C : N i C : S omjere. Na temelju rezultata ove radnje, predložena je gruba granica hidrofilnosti-hidrofobnosti OT (NPA = 0,083). NPA vrijednosti iznad ove granice ukazuju na hidrofobniju i reaktivniju OT, dok vrijednosti ispod nje upućuju na prisutnost hidrofilnije i inertnije OT. Također su ispitana optimizirana voltametrijska mjerenja PAT-a na potenciostatu novije generacije bez fazne osjetljivosti kako bi se osigurala dosljednost mjerenja PAT na modernim instrumentima.Organic carbon serves as a crucial indicator of global change, participating in diverse biogeochemical processes within marine environments. This study investigates changes in the qualitative and quantitative properties of organic matter (OM), a complex mixture of organic compounds with varying characteristics that respond to changing environmental conditions in the unique, stratified eutrophic marine environment of Rogoznica Lake – Zmajevo oko (RL) on the eastern coast of the Adriatic Sea. RL exhibits rapid responses to environmental changes, rendering it ideal for studying numerous biogeochemical processes influenced by these changes. Noteworthy changes include water column warming, deoxygenation, and the accumulation of toxic sulfides and ammonia. Long-term analysis (1996 - 2020) of RJ reveals specific dynamics of OM, including the accumulation of particulate organic carbon (POC) in the water column and dissolved organic carbon (DOC) in the anoxic bottom layer. Quantitative and qualitative changes in OM, particularly related to surface active substances (SAS), the most reactive subset of organic carbon, have been confirmed. Electrochemical analysis, especially the parameter of normalized surface activity (NSA), has proven to be a reliable indicator of changes in marine DOC. Principles of OM characterization were further examined in eutrophic samples (up to 320 mg L-1 od DOC and POC and SAS up to 15 mg L-1) from the northern and central Adriatic, using stable isotopes δ13C, δ15N, and δ34S, as well as C : N and C : S ratios, to investigate the origin of OM and biogeochemical processes in the studied marine ecosystems. Based on the dissertation's findings, a rough threshold of hydrophilicity-hydrophobicity of OM (NSA = 0.083) is proposed. NSA values above this threshold indicate more hydrophobic and reactive OM, while values below it suggest the presence of more hydrophilic and inert OM. Additionally, optimized voltammetric measurements of SAS on a phase-insensitive potentiostat of the latest generation were examined to ensure measurement consistency of SAS in modern instruments
Učinak korištenja vlažnih lipidnih filmova, dobivenih fuzijom vezikula, na elektroformaciju divovskih unilamelarnih vezikula s obzirom na različite lipidne sastave i naboj, koncentraciju kolesterola i ionsku snagu otopine
No full textThe long-term aim of this research is to investigate the properties of cholesterol bilayer domains (CBDs). Before starting experimental work, we conducted a detailed literature search and wrote a review article about all membrane models and experimental methods suitable for studying properties of CBD domains. We also described in details their known properties and functions in biological membranes. Our motivation stemmed from the beneficial role of CBDs in protecting the eye lens from cataract development and maintaining its homeostasis. Based on this knowledge we chosen giant unilamellar vesicles (GUVs) as an appropriate model for studying lipid portion of the fiber cell plasma membranes of the eye lens. GUVs are widely used as membrane models in studies of membrane properties, with the electroformation method being the most common approach for their production. However, several factors can affect the success of GUV electroformation. Common challenges include high cholesterol (Chol) concentrations, the use of lipid mixtures containing charged lipids, and solutions with elevated ionic strength. High Chol concentrations pose a particular problem for the traditional electroformation protocol, which involves drying the lipid film by fully evaporating the organic solvent. During this process, anhydrous Chol crystals can form, which do not integrate into the lipid bilayer, resulting in a lower Chol concentration in the vesicle bilayer compared to the original lipid mixture. To address the issue of artifactual Chol demixing, we have modified the electroformation protocol by introducing rapid solvent exchange, ultrasonication, plasma cleaning, and spin-coating techniques for the reproducible production of GUVs from damp lipid films. A high yield of GUVs was achieved for Chol/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) samples with mixing ratios ranging from 0 to 2.5. At Chol/POPC mixing ratios greater than 1,5, where the GUVs may contain Chol bilayer domains (CBDs), a significant decrease in the average GUV diameter is measured. It is about 40% lower compared to that of the pure POPC bilayer. This modified approach not only minimizes Chol demixing but also successfully produces GUVs from lipid mixtures containing charged lipids and ionic solutions as the internal medium. We prepared GUVs from mixtures with up to 60 mol% of the charged lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-L-serine (POPS) and formed GUVs in low-concentration NaCl solutions.Dugoročni cilj ovog rada je istraživanje svojstava čiste kolesterolove domene. Prije početka
eksperimentalnog rada, istražili smo literaturu te napisali detaljni pregledni članak o različitim
membranskim modelima i eksperimentalnim tehnikama prikladnima za istraživanje tih domena. Sva
poznata svojstva i funkcije čiste kolesterolove domene su opisane. Glavna motivacija za istraživanje su
istraživanje funkcija domene u leći oka, gdje ta domena omogućuje homeostazu stanice i ima zaštitnu
funkciju tijekom razvoja katarakte. Odlučili smo koristiti divovske unilamelarne vezikule (DUV) kao
prikladan model za stanične membrane vlaknastih stanica leće oka. DUV-ovi se koriste kao membranski
modeli za istraživanje osobina bioloških membrana, pri čemu je elektroformacija najčešće primjenjivana
metoda za njihovo formiranje. Međutim, mnogo čimbenika može utjecati na uspjeh elektroformacije DUV-ova. Neki od izazova uključuju upotrebu visoke koncentracije kolesterola, nabijenih lipida i korištenje
otopine s ionskom snagom. Visoke koncentracije kolesterola predstavljaju poseban problem za
tradicionalni protokol, koji uključuje sušenje lipidnog filma. Tijekom ovog procesa mogu se formirati
kolesterolovi kristali koji se ne ugrađuju u vezikulu, što rezultira nižom koncentracijom kolesterola u
vezikuli nego u izvornoj smjesi lipida. Kako bismo se riješili problemom izlučivanja kolesterola,
modificirali smo protokol elektroformacije korištenjem različitih metoda kao što su: brza izmjene otapala,
sonikacija, čišćenje elektrode plazmom i brzo razmazivanje. Modificirani elektroformacijski protokol
omogućuje reproducibilnu proizvodnju DUV-ova za različite omjere kolesterola i 1-palmitnska-2-
oleoinska-sn-glicero-3-fosfokolina (POPC) od 0 do 2.5, uz minimiziranje izlučivanja kolesterola. Za
omjere kolesterol/POPC veće od 1.5 izmjeren je pad drastični promjera DUV-ova. Promjer se smanjio oko
40% u usporedbi s čistom POPC membranom. Osim formiranja DUV-ova s visokom koncentracijom
kolesterola, uspješno smo formirali DUV-ove koristeći nabijene lipide (1-palmitoil-2-oleoil-sn-glicero-3-
fosfo-L-serin, POPS) i ionske otopine s niskom koncentracijom NaCl-a
Hydromorphological changes and sensitivity assessment of the Orljava River
No full textU ovome su radu istražena hidromorfološka obilježja i promjene rijeke Orljave od kraja 19. stoljeća na temelju kojih je procijenjena morfološka osjetljivost rijeke. Promjene u morfologiji korita poput vijugavosti, širine i bočnog kretanja analizirane su pomoću kartografskih izvora i podataka daljinskih istraživanja. Promjene korita na razini meandara istražene su dvogodišnjim monitoringom bespilotnom letjelicom i GNSS prijemnikom. Utvrđene značajne morfološke promjene rijeke uzrokovane su prvenstveno antropogenim utjecajima. Najznačajniji dugoročni utjecaj jest kanaliziranje i izravnavanje korita. Na području Požege, duljina toka je od kraja 19. stoljeća skraćena za više od 30 %. U posljednjih dvadesetak godina, uklanjanje priobalne vegetacije u sklopu mjera obrane od poplava dovelo je do značajnog povećanja bočnog kretanja korita, mjestimice i do četiri puta. Antropogeno presijecanje meandara dodatno destabilizira korito povećanjem nagiba i snage toka. Predlaže se upravljanje rijekom koje omogućuje što prirodnije funkcioniranje riječnog sustava, uključujući obnovu priobalne vegetacije, revitalizaciju naplavnih ravnica i očuvanje prirodne vijugavosti i slobodnog bočnog kretanja rijeke.This study examines the hydromorphological characteristics and changes of the Orljava River since the late 19th century, assessing the river's morphological sensitivity. Morphometric parameters such as sinuosity, channel width, and lateral migration were analyzed using cartographic sources and remote sensing data. Meander morphology at selected locations was monitored over a two-year period using a drone and a high-precision GNSS receiver. Significant changes in the channel morphology have been primarily attributed to human impacts, with channelization and river straightening identified as the most impactful long-term changes. In the Požega urban area, the river's length has been reduced by more than 30% since the late 19th century. Over the past twenty years, the removal of riparian vegetation as part of flood defense measures has led to a significant increase in lateral channel migration—up to four times in some locations. Anthropogenic meander cutoffs further destabilize the channel by increasing slope and stream power. A more nature-based river management approach is recommended, including riparian vegetation restoration, floodplain revitalization, and preservation of natural channel sinuosity and migration
Rodne pogrdnice : semantička, etička i politička dimenzija
No full textBy combining philosophy of language, political philosophy, and epistemology, the dissertation explores the ethical and political dimensions of slurs, areas that have been understudied despite recent increased philosophical interest. Slurs are a part of the pejorative cluster, and they express derogatory attitudes towards their targets. Slurs are the most used vehicle of hate speech which makes them a critical focus for understanding the broader phenomenon of hate speech. The main goal of the thesis is to address the harm caused by slurs that do not traditionally fit into the category of hate speech. Namely, some slurs do not legally qualify as hate speech but still cause significant harm, both individually and collectively. The most typical examples of these kinds of slurs are gendered slurs for women, such as whore, slut, etc. The idea that gendered slurs target women as a group and not just individuals has been challenged, and the thesis presents a possible answer to this challenge by augmenting existing theories of slurs. Namely, I utilize Miščević’s (2016) idea of slurs having layers and suggest a new layer: the negative identity-prejudicial stereotype layer, inspired by Fricker’s (2007) work. Finally, the pivotal aspect of the thesis is the introduction of the novel concept of derogatory-labeling injustice which explains how such slurs (prime examples being gendered slurs for women) cause significant harm through negative identity prejudice evoked by their literal uses. The dissertation, as stated, augments existing theories of slurs and highlights the role of negative identity prejudice in generating this kind of injustice. By examining slurs through the lens of philosophy of language, social and political philosophy, and epistemology, the thesis contributes to a deeper understanding of slurs and their impact.Kombinirajući filozofiju jezika, političku filozofiju i epistemologiju, disertacija istražuje etičke i političke dimenzije pogrda. Navedena područja nedovoljno su istražena unatoč nedavnom povećanom zanimanju za njih u filozofiji jezika. Pogrde podpadaju pod pogrdnice, a izražavaju negativne stavove prema žrtvama. Pogrde su najčešće korišteno sredstvo govora mržnje što ih čini kritičnom točkom fokusa za razumijevanje šireg fenomena govora mržnje. Glavni cilj ovoga rada jest istražiti štetu koju čine one pogrde koje se tradicionalno ne uklapaju u kategoriju govora mržnje. Naime, neke pogrde se pravno ne kvalificiraju kao govor mržnje, ali ipak uzrokuju značajnu štetu, sličnu onoj koju uzrokuje govor mržnje. Najtipičniji primjeri ove vrste pogrda su rodne pogrde za žene, kao što su kurva, drolja, itd. Ideja da su rodne pogrde usmjerene na žene kao skupinu, a ne samo pojedince, je dovedena u pitanje, a rad predstavlja mogući odgovor na taj izazov proširenjem postojećih teorija o pogrdama. Naime, koristim se Miščevićevom (2016) idejom da pogrde imaju slojeve te predlažem novi sloj, a to je negativni identitetsko-predrasudni stereotip, inspiriran radom Mirande Fricker (2007). Ključni aspekt disertacije je uvođenje novog koncepta nepravde – nepravde pogrdnog etiketiranja – koji objašnjava mehanizme takvih pogrda (glavni primjeri takvih pogrda su pogrde za žene). Odnosno, dokazuje se da takve vrste pogrda, u njihovoj doslovnoj upotrebi, uzrokuju značajnu štetu evocirajući negativne predrasude o identitetu. Disertacija, kao što je navedeno, proširuje postojeće teorije o pogrdama i naglašava ulogu predrasuda o negativnom identitetu u stvaranju nove vrste nepravde. Proučavajući pogrde kroz prizmu filozofije jezika, socijalne i političke filozofije te epistemologije, rad pridonosi dubljem razumijevanju pogrda i njihovog utjecaja
SOX2, JAGGED1, β-catenin, vitamin D receptor and NOTCH2 expression patterns during early development and innervation of the human inner ear
No full textUVOD: Gubitak sluha je jedan od najčešćih invaliditeta u svijetu. Može se podijeliti na senzorineuralni, konduktivni i mješoviti. Senzorineuralni gubitak sluha je najčešći tip i uzrokovan je lezijama u unutarnjem uhu, slušnom živcu ili neuronima slušnog puta. Razumijevanje događaja i signalnih putova koji pokreću formiranje unutarnjeg uha ključno je za određivanje mogućih uzroka kongenitalnog gubitka sluha. Cilj ove disertacije je analizirati inervaciju i izražaj SOX2, JAGGED1, β-katenina (CTNNB1), receptora vitamina D (VDR) i NOTCH2 tijekom ranog razvoja ljudskog unutarnjeg uha koristeći imunohistokemiju. MATERIJALI I METODE: U ovom presječnom istraživanju bilo je uključeno ukupno 12 uzoraka ljudskog unutarnjeg uha podijeljenih u 3 skupine po razvojnim tjednima (5-6W, 7-8W i 9-10W). Urađeno je imunofluorescencijsko bojenje za usporedbu vremensko-prostorne raspodjele transkripcijskog faktora SOX2 i transmembranskog proteina JAGGED1, proteina β-katenina i nuklearnog receptora VDR te receptora NOTCH2. Također je primjenom imunofluorescencije određen raspon inervacije prosenzornih domena ljudskog unutarnjeg uha koristeći biljeg acetilirani alfa tubulin. REZULTATI: Izražaj SOX2 bio je pretežno nuklearni u svim promatranim stadijima razvoja pužničnog kanala i vestibularnog aparata. Membranski izražaj JAGGED1 bio je lokaliziran zajedno sa membranskim izražajem SOX2 u svim promatranim razvojnim stadijima pužničnog kanala i vestibularnog aparata, pri čemu je izražaj SOX2 bio dosljedno veći. Pri 5-6 tjednu nakon oplodnje (tj) nisu bila prisutna živčana vlakna u pužničnom kanalu, u 8. tj živčana vlakna su dosegla epitel pužničnog kanala. Živčana vlakna u vestibularnom aparatu (makule u razvoju) vidljiva su pri 5-6 tj. U 7-8 tj i 9-10 tj makule u razvoju su gusto inervirane. Beta-katenin je pri 5-6 tj pokazao nuklearno bojenje u epitelu krova pužničnog kanala, što znači da je tu aktivnakanonska WNT signalizacija. Isti obrazac ekspresije je vidljiv pri 7-8 tj. Pri 9-10 tj većina stanica pužničnog kanala imala je membranski uzorak bojenja, što ukazuje da kanonska WNT signalizacija nije aktivna. U vestibularnim regijama, pri 5-6 tj, beta-katenin je pokazao nuklearnu ekspresiju u prijelaznom i tamnom epitelu kao i u endolimfatičkom kanalu. Sličan obrazac bojenja viđen je pri 7-8 tj. Pri 9-10 tj aktivna kanonska WNT signalizacija uglavnom je bila prisutna u neosjetnim područjima epitela unutarnjeg uha. Izražaj VDR-a u pužničnom kanalu tijekom 5-6 tj, 7-8 tj i 9-10 tj bio je nuklearni u područjima krova pužničnog kanala. U vestibularnim regijama tijekom 5-6 tj, 7-8 tj i 9-10 tj nuklearni izražaj VDR-a bio je vidljiv u makulama i ampularnim kristama u razvoju te u neosjetnom tamnom staničnom epitelu u kojem je bio veći. NOTCH2 nije bio izražen u epitelu unutarnjeg uha u razvoju. ZAKLJUČAK: SOX2 i JAGGED1 izraženi se u prosenzornim domenama ljudskog unutarnjeg uha između 5-10 tj, pri čemu je izražaj SOX2 dosljedno veći. Živčana vlakna mogu se vidjeti kako prodiru kroz vestibularne regije (makule u razvoju) ljudskog unutarnjeg uha pri 6.tj i u epitelu dna pužničnog kanala pri 8. tj. Izražaj beta-katenina i VDR-a je najveći uneosjetnom epitelu vestibularnih regija, većinom je membranski i prisutan je u svim analiziranim razvojnim stadijima ljudskog unutarnjeg uha. Međusobni izražaj beta-katenina i VDR-a pokazao se kao antagonističan tijekom analiziranih razvojnih stadija ljudskog unutarnjeg uha.INTRODUCTION: Hearing loss is one of the most common disabilities in the world. It can be divided into sensorineural, conductive or mixed. Sensorineural hearing loss is the most common type and can be caused by lesions in the inner ear, cochlear (auditory) nerve, or neurons of the auditory pathway. Understanding the events and signaling pathways that drive inner ear formation is crucial for determining the possible causes of congenital hearing loss. The aim of this dissertation is to analyze the innervation and expression of SOX2, JAGGED1, β-catenin (CTNNB1), vitamin D receptor (VDR), and NOTCH2 in the inner ears of human using immunohistochemistry. MATERIALS AND METHODS: In this cross-sectional research, we investigated a total of 12 human developing inner ear samples divided into 3 groups by development weeks (5-6W, 7-8W and 9-10W). Immunofluorescence staining was performed to compare the temporal and spatial distribution of transcription factor SOX2 and protein JAGGED1, β-catenin protein and nuclear receptor VDR, and receptor NOTCH2. Also, using immunofluorescence, the range of innervation of the prosensory domains of the human inner ear was determined using a marker acetylated-alfa-tubulin. RESULTS: SOX2 expression was predominately nuclear in all observed stages of development of the cohlear duct and vestibular apparatus. The membranou expression of JAGGED1 was co-localized with the membranous expression of SOX2 in all observed developmental stages of the cochlear canal and vestibular apparatus, where the expression of SOX2 was consistently higher. At 5-6W no nerve fibers were present in the cochlear duct, at 8W the nerve fibers reached the epithelium of the cochlear duct. Nerve fibers in the vestibular apparatus (prospective maculae) are visible at 5-6W. In 7-8W and 9-10W the developing maculae are densely innervated. Beta-catenin at 5-6W showed nuclear staining in the epithelia of the roof region of the cochlear duct, which means that canonical WNT signaling is active. The same expression pattern is visible at 7-8W. At 9-10 W, most cochlear duct cells had a membranous staining pattern, indicating that canonical WNT signaling is not active. In the vestibular regions, at 5-6W, beta-catenin showed nuclear expression in the transitional and dark cell epithelium as well as in the endolymphatic duct. A similar staining pattern was seen at 7-8W. At 9-10W, active canonical WNT signaling was mostly present in non-sensitive areas of the inner ear epithelium. VDR expression in the cochlear duct during 5-6W, 7-8W, and 9-10W was nuclear in the roof regions of the cochlear duct. In the vestibular apparatus during 5-6W, 7-8W and 9-10W nuclear expression of VDR was visible in developing maculae and cristaampullares and in non-sensory dark cell epithelium where it was stronger. NOTCH2 expression was not present in the epithelium of the developing inner ear. CONCLUSION: SOX2 and JAGGED1 are expressed in the prosensory domains of the human inner ear between 5–10 W, with SOX2 expression being consistently more extensive. Nerve fibers can be seen penetrating the vestibular maculae of the human inner ear at 6 W and at the base of the cochlear duct at 8 W. CTNNB1 and VDR are expressed throughout the inner ear epithelium during early development, with non-sensory and vestibular regions demonstrating the strongest expression
Development and application of immobilized composite photocatalysts obtained by sol-gel process
No full textU ovom radu korišten je fotokatalizator titan(IV) oksid (TiO2) zbog svoje dostupnosti, kemijske i biološke inertnosti, ali i dobrih fotokatalitičkih svojstava. Da bi se olakšala njegova primjena u usporedbi sa suspendiranim oblikom provedena je njegova imobilizacija na mrežu od staklenih vlakana sol-gel postupkom. Istraživano je mogu li se u procesu sušenja primijeniti i mikrovalovi zbog same brzine sušenja i pripreme fotokatalizatora te je utvrđen negativan utjecaj. Daljnje istraživanje bilo je usmjereno prema dopiranju TiO2 višeslojnim ugljičnim nanocijevima (MWCNT) i grafen oksidom (GO) s ciljem poboljšanja fotokatlitičke aktivnosti TiO2 pri Sunčevom zračenju. Dopiranje je provedeno s različitim udjelima MWCNT u odnosu na masu TiO2: 1,5, 5, 10, 25, 50 i 100 mas. %. Najbolju fotokatalitičku aktivnost pokazao je fotokatalizator dopiran s 10 mas.% MWCNT u usporedbi s pripravljenim TiO2 fotokatalizatorom. Na temelju istraživanja fotokatalizatora pripremljenog s MWCNT pripremljeni su i fotokatalizatori dopirani s GO i to u udjelima od 5, 10 i 25 mas. %. Rezultati su pokazali da GO negativno utječe na fotokatalizu. Fotokatalitička aktivnost pripremljenih fotokatalizatora je praćena razgradnjom modalne otopine salicilne kiseline UV-Vis spektrofotometrom pod simuliranim Sunčevim zračenjem. Salicilna kiselina je korištena kao primjer mikroonečišćenja koje se uvelike pojavljuje u okolišu jer ima široku primjenu u lijekovima i kozmetičkim proizvodima. Nadalje, istražena je postojanost pripravljenih fotokatalizatora te su rezultati starenja na zraku i u vodi pokazali da je moguća višekratna uporaba pripremljenih fotokatalizatora bez značajnog opadanja njegove aktivnosti.It was investigated whether microwaves could also be used for the drying process due to the speed of drying and the preparation of the photocatalyst, and a negative impact was determined. Further research was focused on the doping of titanium(IV) oxide (TiO2) with multi wall carbon nanotubes (MWCNT) and graphene oxide (GO) with the aim of improving the photocatalytic activity of TiO2 under solar radiation. The doping was carried out with different proportions of MWCNT in relation to the mass of the TiO2: 1.5, 5, 10, 25, 50 and 100 wt. %. The photocatalyst doped with 10 wt. % MWCNT showed the best photocatalytic activity compared to the photocatalyst prepared with TiO2. Based on the study of the photocatalyst prepared with MWCNT, photocatalysts doped with GO were also prepared in proportions of 5, 10 and 25 wt. %. The results showed that GO has a negative effect on the photocatalysis. The photocatalytic activity of the prepared photocatalysts was monitored by decomposing the salicylic acid modal solution with a UV-Vis spectrophotometer under simulated solar radiation. Salicylic acid was used as an example of a micropollutant that is widely present in the environment as it is often used in pharmaceuticals and cosmetic products. Furthermore, the stability of the prepared photocatalysts was investigated, and the results of aging in air and in water showed that repeated use of the prepared photocatalysts is possible without a significant decrease in its activity
Stohastičko-determinističko modeliranje toplinskog odziva ljudskog tijela izloženog zračenju visokih frekvencija
No full textFully analytically solvable and simple, stochastic-deterministic model consisting of a vertical dipole antenna of finite length and of a simple model of the human body is presented in this thesis. Efficient deterministic model for incident field dosimetry, internal field dosimetry and thermal dosimetry are developed. In the framework of stochastic modelling of the thermal response of the human body, the influence of uncertainty in the set of input parameters on the resulting temperature elevation in steady-state is quantified. Finally, in the stochastic part of the thermal dosimetry, a sensitivity analysis is performed, thus providing the assessment of the influence of each of the input parameters and their mutual influence on the output value of interest.
The application of analytical procedures provides fast and complete dosimetry for realistic scenarios in terms of exposure to high frequency radiation from specific antenna systems. By applying stochastic modelling of the body's thermal response, it is possible to estimate the uncertainty of temperature rise due to the uncertainty of input parameters (thermal conductivity, thickness of tissue layers) that cannot be determined by in vivo measurement.U ovom radu prikazan je potpuno analitički rješiv i jednostavan, stohastičko-deterministički model koji se sastoji od vertikalne dipolne antene konačne duljine i jednostavnog modela ljudskog tijela. Razvijen je učinkovit deterministički model za dozimetriju upadnog polja, dozimetriju unutarnjeg polja i toplinsku dozimetriju. U okviru stohastičkog modeliranja toplinskog odgovora ljudskog tijela, kvantificira se utjecaj nesigurnosti u skupu ulaznih parametara na rezultirajuće povišenje temperature u stacionarnom stanju. Na kraju, u stohastičkom dijelu toplinske dozimetrije provodi se analiza osjetljivosti, čime se daje procjena utjecaja svakog od ulaznih parametara i njihov međusobni utjecaj na izlaznu vrijednost od interesa.
Primjena analitičkih postupaka omogućuje brzu i potpunu dozimetriju za realne scenarije izloženosti visokofrekventnom zračenju specifičnih antenskih sustava. Primjenom stohastičkog modeliranja toplinskog odgovora tijela moguće je procijeniti nesigurnost porasta temperature zbog nesigurnosti ulaznih parametara (toplinska vodljivost, debljina slojeva tkiva) koji se ne mogu odrediti in vivo mjerenjem
The effect of liver steatosis on the course and outcome of sepsis
No full textOvo prospektivno opservacijsko istraživanje u trajanju od 16 mjeseci uključilo je odrasle bolesnike koji su bili hospitalizirani zbog sepse stečene u vanbolničkim uvjetima. Od 378 uključenih, u njih 46% dijagnosticiran je NAFLD. Bolesnici s NAFLD-om bili su stariji te su češće ispunjavali kriterije metaboličkog sindroma. Nisu uočene razlike u ishodištu i etiologiji sepse. Bolesnici s NAFLD-om pokazali su veću prevalenciju akutne bubrežne insuficijencije, potrebe za hemodijalizom te povećanu potrebu za invazivnom mehaničkom ventilacijom. Bolnički mortalitet bio je gotovo dvostruko viši u grupi s NAFLD-om. Multivarijatna analiza pokazala je neovisnu povezanost NAFLD-a s mortalitetom bez obzira na druge čimbenike metaboličkog sindroma. Također je FAST skor identificiran kao precizan prediktor mortaliteta. Nadalje, eksperimentalni biomarkeri CK-18 i adiponektin evaluirani su kao markeri statusa jetre. U bolesnika s NAFLD-om razine CK-18 u krvi bile su povišene, dok su razine adiponektina snižene i obrnuto za non-NAFLD skupinu, što bi moglo biti korisno u probiru, dijagnostici i praćenju bolesnika s jetrenom steatozom. Ovo istraživanje ističe učestalost NAFLD-a među bolesnicima sa sepsom te značajan utjecaj NAFLD-a na ishod liječenja. Specifični biomarkeri kao što su CK-18 i adiponektin mogu biti korisni u dijagnostici i praćenju bolesnika s jetrenom steatozom, dok FAST skor može koristiti kao prediktor mortaliteta.This prospective observational study, conducted over 16 months, included adult patients who were hospitalized due to community-acquired sepsis. Of the 378 patients, 46% were diagnosed with NAFLD. These patients were older and more frequently met the criteria for metabolic syndrome. No differences were observed in the etiology of sepsis. Patients with NAFLD showed a higher prevalence of acute kidney injury, need for hemodialysis, and the need for invasive mechanical ventilation. Hospital mortality was almost twice as high in the NAFLD group. Multivariate analysis showed an independent association of NAFLD with mortality regardless of other factors of metabolic syndrome. Also the FAST score as an accurate
predictor of mortality was identified. Furthermore, biomarkers CK-18 and adiponectin were evaluated as markers of liver status. In patients with NAFLD, blood levels of CK-18 were elevated, while adiponectin levels were decreased, and vice versa for the non-NAFLD group. Our study highlights the prevalence of NAFLD among patients with sepsis and the significant
impact of NAFLD on treatment outcomes. Specific biomarkers such as CK-18 and adiponectin may be useful in diagnosing and monitoring patients with hepatic steatosis, while the FAST score can serve as a predictor of mortality
Comparison of the attack structures of the North American (NHL) and Russian (KHL) ice hockey leagues in playoff matches
No full textOsnovni cilj ovog istraživanja bio je utvrditi razlike u strukturi napada između Sjevoernoameričke hokejaške lige (NHL) i Kontinentalne hokejaške lige (KHL). Preduvjet za ostvarivanje cilja bio je precizno definiranje struktura napada hokeja na ledu odnosno njihovih početaka, napadačkih akcija i kraja, s brojem odavanja i trajanjem akcije. Za potrebe istraživanja analizirano je po 20 nasumično odabranih utakmica doigravanja obiju liga u sezoni 2017/18. Iz njih je generirano 16786 entiteta napada, od čega je iz ruske lige 7793 (NKHL= 7793), a iz sjevernoameričke lige 8993 (NNHL=8993) entiteta napada.
Hi-kvadrat (χ2) testom dobiveno je postojanje statistički značajne razlike između NHL-a i KHL-a u kvalitativnim varijablama; Početak napada (χ2=99,3582, df=13, p=0,00000), u varijablama Kontrolirani izlaz iz trećine, Pregrupiranje, Oduzeta pločica, Izlasci pod pritiskom zaokretom iza vrata i dodavanje gore i Obrambeni odbijanac; Napadačka akcija (χ2=101,0846, df=26, p=0,0000) u varijablama Upucavanje pločice u protivničku zonu, Ispucavanje pločice iz obrambene zone, Dodavanje od iza vrata, Izravni napad s jednakim brojem igrača i viškom igrača te udarci s ograde; Završetak napada (χ2=16,2091, df=7, p=,023274) u varijablama Predana pločica, Oduzeta pločica i Blokirani udarci. Također, t-testom je utvrđena je statistički značajna razlika između NHL-a i KHL-a u varijablama trajanje napada (t=13,3816, p=0,0000) i broju dodavanja po napadu (t=8,0807, F=1,41 p=0,0000).
Sekundarno, dobivena je razlika između pobjedničkih i poraženih ekipa i to u početku napada u varijabli Oduzeta pločica u obrambenoj zoni (t = 2,171, p=0,034). Kod napadačkih akcija pobjedničke i poražene ekipe razlikuju se u varijabli Ispucavanje pločice iz obrambene zone (t=3,442, p = 0,001), Upucavanje pločice u protivničku trećinu (t= -2,456, p=0.017) te Izravnim napadom s viškom igrača (U= 349,00, Z=2,501, p=0,012), dok se kod završne akcije razlikuju samo u varijabli Postignuti pogodak (U=241,50, Z=3,879, p=0,000). Također, pobjedničke i poražene ekipe razlikuju se u trajanju napada (t=2,490, p=0,012) gdje napadi traju duže i imaju više dodavanja (t = 3,189, p=0,001). Regresijskom analizom ustanovljena je povezanost varijabli napada s konačnim rezultatom pozitivno u varijablama Postignuti pogodak,
Izbacivanje pločice iz obrambene zone i Dodavanje prema dolje u odgođenom napadu te negativno Udarac s ograde, Pripucavanje i Upucavanje pločice u protivničku zonu.The main objective of this research is to determine differences in phase of attack beetween National Hockey League (NHL) and Kontinental Hockey League (KHL). The precondition for achieving the goal was to precisely define the structure of the ice hockey attack, i.e. its beginnings, attacking action and end of the attack, with the number of shots and the duration of the action. For the purposes of the research, 20 randomly selected playoff games of both leagues in the 2017/18 season were reviewed. From them, 16786 attack entities were generated, of which 7793 (NKHL= 7793) were from the Russian league, and 8993 (NNHL=8993) attack entities from the North American league.
Chi-square test showed the existence of a statistically significant difference between NHL and KHL in qualitative variables: Attack start (χ2=99.3582, df=13, p=0.00000), in the variables Controlled exit from the defending zone, Regrouping, Takeaways, BreakoutsWheel and Quick Up and Defensive rebound; Attacking action (χ2=101.0846, df=26, p=0.0000) in the variables Dump puck, Passing from behind the net, Straight attack with Equal strength of players and an excess of players, and shots from fences; Attack completion (χ2=16.2091, df=7, p=0.023274) in the variables Giveaway, Takeaway and Blocked Shots. Also, the t-test revealed a statistically significant difference between NHL and KHL in the variables attack duration (t=13.3816, p=0.0000) and number of passes per attack (t=8.0807, F=1.41 p=0.0000).
Secondary, the difference between the winning and losing teams was obtained at the beginning of the attack in the variable Takeaway in Defensive Zone (t=2.171, p=0.034). In terms of attacking actions, the winning and defeated teams differ in the variable Defensive zone Dump (t=3.442, p = 0.001), Dump puck (t= -2.456, p=0.017) and Straight attack with odd players (U=349.00, Z=2.501, p=0.012), while in the final action they differ only in the Scored goal variable (U=241.50, Z=3.879, p = 0.000). Also, winning and losing teams differ in the duration of attacks (t=2.490, p= 0.012), where attacks last longer and have more passes (t = 3.189, p=0.001). Regression analysis established a positive connection between the attack variables
and the final result in the variable Goal, Defensive zone dump and Offensive zone Pass down low, and negatively Shoot from board, Rebound and Dump the puck
Intangible cultural heritage in sustainable development of tourism
No full textŠirok utjecaj turizma i turističkih kretanja ističe važnost i posebnu važnost potrebe za upravljanjem rastom i razvojem, osobito u kontekstu održivog razvoja. Turizam već duže stavlja naglasak na autohtone, jedinstvene destinacije bogate sadržajem stvarajući specifične oblike turizma kao što je kulturni turizam. Nematerijalna kulturna baština predstavlja kulturni resurs koji se može integrirati u turističke aktivnosti na više načina te doprinijeti održivom razvoju turizma. Istraživački ciljevi usmjereni su ponajprije na definiranje i razumijevanje održivog razvoja turizma, kulturnog turizma i kulturnih turista te nematerijalne kulturne baštine kao dijela kulture, ali i dijela turističke ponude. U teorijskom dijelu rada analizira se održivi razvoj s osvrtom na prekretnice koje su oblikovale današnje shvaćanje održivog razvoja turizma. Raspravlja se o problemima definiranja i kategoriziranja kulturnog turizma i donose se specifičnosti koje određuju kulturne turiste i kulturne proizvode. Središte ovoga rada čini nematerijalna kulturna baština, u kojim se oblicima pojavljuje i na koji se način osigurava njezino očuvanje. Turistička valorizacija nematerijalne kulturne baštine u osnovi predstavlja pretvorbu kulturnog resursa u turistički resurs. Posljedice utječu na sam turizam i turiste tako što ona nije samo atrakcija za posjetitelje nego i ključni element u oblikovanju autentičnih turističkih iskustava. Uz niz pozitivnih učinaka, lokalna se zajednica može susresti i s negativnim posljedicama povećane turističke posjećenosti. Oprez i planiranje nužni su kako nematerijalna kulturna baština kao dio turističke ponude ne bi izgubila svoju svrhu i važnost za lokalnu zajednicu ili autentičnost. Integracija nematerijalne kulturne baštine u turističke projekte obogaćuje turističko iskustvo, potiče kulturnu razmjenu i podupire dobrobit zajednice. Ciljevi empirijskog dijela ovog rada usmjereni su na istraživanje utjecaja turističke valorizacije nematerijalne kulturne baštine na održivi razvoj turizma, posebno smanjenjem sezonalnosti i povećanjem turističke potrošnje. Ključni aspekti uključuju produljenje boravka turista u destinaciji, privlačenje dolazaka izvan glavne sezone te stvaranje atraktivne ponude koja omogućuje kontinuirano zanimanje turista tijekom cijele godine. Nematerijalna kulturna baština, kao jedinstven i neponovljiv resurs, ima značajnu ulogu u oblikovanju turističkih proizvoda koji zadovoljavaju suvremene turističke potrebe. Pozitivni ekonomski učinci turističke valorizacije nematerijalne kulturne baštine ogledaju se u povećanoj potrošnji turista, rastu prihoda lokalnog stanovništva i jačanju lokalnih gospodarstava. Istodobno, nositelji baštine dobivaju priliku za očuvanje i revitalizaciju svojih tradicija dok sinergija kulturnog turizma i očuvanja baštine doprinosi uravnoteženom razvoju zajednica i destinacija. Takav pristup ne samo da pridonosi održivosti turizma već i jača društvenu koheziju te potiče širu svijest o važnosti očuvanja kulturne baštine kao temelja identiteta i turističke atraktivnosti.The broad impact of tourism highlights the importance and special significance of the need for management, particularly in the context of sustainable development. Tourism has long emphasized indigenous, unique destinations rich in content, creating specific forms of tourism such as cultural tourism. Intangible cultural heritage represents a cultural resource that can be integrated into tourist activities in various ways and contribute to the sustainable development of tourism. To gain a deeper understanding of the research problem and ease the research process the research questions are identified for both the conceptual and for the empirical part of this dissertation. Each research question represents a research goal, or part of it. In the conceptual part of the dissertation the research goals, with accompanying research questions include the following:
Research question
What is sustainable tourism development?
Research goal
What are the "rules" of tourism development if it is to be sustainable? Who is involved in the process of tourism development when it is sustainable? Define sustainable tourism development, the fundamental guidelines and principles of sustainable tourism development, and the relevant stakeholders
Research question
How can sustainable tourism development be measured?
Research goal
Display indicators of sustainability in tourism What are the characteristics of sustainable development of cultural tourism?
Research question
What are the specific aspects of sustainability for tangible and intangible cultural heritage?
Research goal
Define sustainable development of cultural tourism and the specifics of sustainability in tangible and intangible cultural heritage
Research question
What is cultural tourism? Are there any differences within cultural tourism? Who are the participants of cultural tourism? Are there any differences among them? What makes them special or different from other tourists? What is the subject of consumption in cultural tourism? What are the unique features of a cultural product in tourism?
Research goal
Define cultural tourism, cultural tourists and cultural tourism product and distinguish between the motives and types within cultural tourism.
Research question
What is intangible cultural heritage? What are the main differences between tangible and intangible cultural heritage?
Research goal
Define intangible cultural heritage and its specific characteristics in comparison to tangible cultural heritage.
Research question
Who participates in the preservation of intangible cultural heritage? How do they do it? Are there regulations and standards that protect intangible cultural heritage, and who is responsible for them?
Research goal
Define the organizations involved in the preservation of intangible cultural heritage.
Research question
What is the relationship between intangible cultural heritage and (cultural) tourism? How can intangible cultural heritage be incorporated into tourism?
Research goal
Show the connection between intangible cultural heritage and cultural tourism and explain the tourist valorization of intangible cultural heritage
Research question
What are all the possible consequences of incorporating intangible cultural heritage into tourism on cultural tourism and tourists, on the local population and on the intangible cultural heritage itself?
Research goal
Show the impact of the tourist valorization of intangible cultural heritage on tourism and tourists, on the local community and on the intangible cultural heritage itself
Research question
Are there any specific aspects to pay attention to when incorporating intangible cultural heritage into tourism?
Research goal
Analyse the critical areas of sustainability for tourist-valorised intangible cultural heritage.
This dissertation has six main chapters, five of them are focused on theoretical research of the main topics and the last one is representing the empirical research of impact of intangible culture heritage on sustainable tourism development. The first theoretical chapter analyses sustainable development with a focus on milestones that have shaped the current understanding of sustainable tourism development. This chapter discusses stakeholders involved, indicators and their purpose with emphasis on sustainable cultural tourism development and the particularities regarding intangible cultural heritage. Next chapter discusses the problems of defining and categorizing cultural tourism while showing the different approaches. Further, it thoroughly presents specifics that determine cultural tourists and cultural products. There are several views of cultural tourist’s typology, each of them having a different foundation at its core. Depending on the view, the main determining factors could be motivation, intention, depth of experience and of course, a combination of them. The third theoretical chapter is defining cultural heritage and explaining the difference between tangible and intangible cultural goods. Intangible cultural heritage is the central focus when explaining the various forms and its relevance to the local communities, nations, and mankind as a whole. The preservation of the intangible cultural heritage is a focal point of protection cultural heritage and cultural identities of local communities. There are many national and international institutions taking part in safeguarding intangible cultural heritage. Their main work and achievements are presented. The final theoretical chapter explores the tourist valorization of intangible cultural heritage. What it essentially involves, is the transformation of a cultural resource into a tourist one. These actions are putting the intangible cultural good in the tourist market for consumption. The impacts of this are wide and not only are they affecting tourism, tourists and local communities, but the intangible cultural heritage as well. Consequences on tourism and tourists are mostly positive in a way that intangible cultural tourist product is not only an attraction for visitors, but also a key element in shaping authentic tourist experiences. Impact on the local community, while providing a range of positive effects, may also show some negative consequences of increased tourist visitation. Some of the main negative effects are displacement of long-time residents due to rising property prices and rents, loss of community identity and cultural heritage due to erosion of cultural norms and values, reduced affordability of local businesses and services, leading to the displacement of small businesses and threat of relocation away from ancestral land. Finally, the intangible cultural heritage is tempted to adjust itself in order to accommodate tourist demand and appear more presentable. Caution and careful planning are essential to ensure that intangible cultural heritage as part of the tourist offer does not lose its purpose and significance for the local community or its authenticity. The integration of intangible cultural heritage into tourist projects enriches the tourist experience, fosters cultural exchange, and supports community well-being. The second part of this dissertation is the empirical part, and it is focused on exploring the specific implication of tourist valorization of intangible cultural heritage on sustainable tourism development. The research questions are transformed to research goals and four main hypotheses are formed. One of the goals was to determine the differences between two researchs, one in 2016. and the other one in 2022.
• H1: There is a statistically significant difference between tourists whose primary motivation for visiting a destination is culture and those with other motivations regarding their socio-demographic variables.
• H2: There is a statistically significant difference in the proportion of tourists whose primary motivation for visiting the destination is culture between 2016 and 2022.
• H3: There is a statistically significant difference between tourists who participated in or learned about the intangible cultural heritage of the destination and those who did not regarding their socio-demographic variables.
• H4: The tourism valorization of intangible cultural heritage has a positive impact on extending tourists' length of stay at the destination.
• H5: The tourism valorization of intangible cultural heritage positively influences the intention to visit the destination outside the main season.
• H6: The tourism valorization of intangible cultural heritage is associated with higher levels of tourist expenditure. The research method used was a structured survey questionnaire. The target segment, or sample, consisted of tourists in the destinations. The research was conducted in two time segments. The first survey was conducted in 2016, and the second survey was conducted in 2022. A total of 1,168 questionnaires went for further processing, with 572 from the first survey and 596 from the second survey. Both surveys were conducted during the peak season in various destinations in Croatia and the Czech Republic. In Croatia, the research was conducted on the island of Pag, in Šibenik, Varaždin, and Slavonia, specifically in Vinkovci. In the Czech Republic, the research was conducted in Prague. In each destination, the survey questionnaire highlighted the intangible cultural heritage associated with or originating from the destination. The research was conducted using the "face-to-face" method with interviewers. The survey questionnaire was available in several languages: Croatian, English, German, Italian, French, Spanish, and Russian. Intangible cultural heritage, as a distinct and valuable tourism resource, plays a crucial role in mitigating seasonality by addressing two critical dimensions: extending the duration of tourists' stays within the destination and attracting visitors during off-peak periods. Empirical findings from the study demonstrate that the valorization of intangible cultural heritage in tourism significantly contributes to elevated levels of tourist expenditure. Furthermore, the research delineates notable sociodemographic distinctions between cultural tourists and those engaging in activities specifically centered on intangible cultural heritage. The comparative analysis of survey data from 2016 and 2022 revealed no statistically significant differences, thereby underscoring the robustness and consistency of findings related to participants’ motivations, behavioral patterns, and expressed intentions. The economic consequences of tourist-valorised intangible cultural heritage are positive for local communities, but also for the bearers of intangible cultural heritage. The synergy between cultural tourism and the preservation of intangible cultural heritage contributes to the sustainable development of communities and tourist destinations. Furthermore, the conclusions drawn can be applied at a practical level to initiate dialogue between the tourist and cultural sectors, fostering a shared holistic approach to preserving intangible cultural heritage and promoting sustainable tourism development. Considering that sustainable tourism development is the only viable path for long-term progress, it is understandable that there are multiple ways to achieve it. This study has demonstrated the significant role of intangible cultural heritage in sustainable tourism development