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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
Land cover and land use changes on the island of Cres in the last 200 years
No full textOvaj rad analizira promjene u zemljišnom pokrovu i načinu korištenja zemljišta na otoku Cresu tijekom posljednjih 200 godina, s naglaskom na utjecaj deagrarizacije, depopulacije i urbanizacije. Korišteni su podaci iz Franciskanskog katastra (1821.), avio snimaka (1968.) i DOF-a (2023.), dok je recentno stanje dodatno analizirano Sentinel-2 satelitskom snimkom i nenadziranom klasifikacijom. Obrada u softveru ArcGIS Pro obuhvatila je klasifikaciju zemljišta na obradive, neobradive, pašnjake i izgrađene površine. Rezultati pokazuju smanjenje poljoprivrednih površina i pašnjaka te širenje neobradivih površina i izgrađenih struktura, osobito duž obale, uslijed turističkog razvoja. Korištenje arhivskih podataka omogućilo je praćenje dugoročnih trendova, dok su daljinska istraživanja pokazala visoku učinkovitost u kvantifikaciji promjena. Ovi rezultati ističu važnost razumijevanja analiziranih procesa za održivo planiranje i upravljanje prostorom.This study analyzes changes in land cover and land use on the island of Cres over the past 200 years, focusing on the impact of deagrarization, depopulation, and urbanization. Data from the Franciscan Cadastre (1821), aerial photographs (1968), and DOF (2023) were used, while the recent period was further analyzed using Sentinel-2 satellite imagery and unsupervised classification. Data processing in ArcGIS Pro included land classification into arable land, non-arable land, pastures, and built-up areas. The results indicate a reduction in agricultural land and pastures, along with an expansion of non-arable and built-up areas, particularly along the coast, due to tourism development. The use of archival data enabled long-term trend monitoring, while remote sensing proved highly effective in quantifying these changes. These findings highlight the importance of understanding the analyzed processes for sustainable spatial planning and land management
Molybdenum complexes with formic acid hydrazide derivatives
No full textU okviru ovog diplomskog rada pripravljena su dva hidrazonska liganda, H2L1 i H2L2, derivati hidrazida mravlje kiseline i 2-hidroksibenzaldehida, odnosno 2-hidroksi-5-nitrobenzaldehida. Reakcijama [MoO2(acac)2] i odgovarajućeg hidrazonskog liganda, u množinskom omjeru 1 : 1, u odgovarajućem otapalu, pripravljeni su kompleksni spojevi molibdena(VI). Mononuklearni kompleksni spojevi, [MoO2(L1)(MeOH)] i [MoO2(L2)(MeOH)], sintetizirani su iz metanola, uz dodatak piridina. Reakcijama u acetonitrilu sintetizirani su mononuklearni kompleksni spoj, [MoO2(L2)(H2O)]·MeCN te polinuklearni kompleksni spojevi, [MoO2(L1)]n i [MoO2(L2)]n. Hidrazonski ligandi i kompleksni spojevi karakterizirani su i analizirani razlikovnom pretražnom kalorimetrijom, infracrvenom spektroskopijom te termogravimetrijskom analizom. Difrakcijom rendgenskog zračenja na jediničnom kristalu određene su molekulske i kristalne strukture liganda H2L1 te kompleksnih spojeva [MoO2(L2)(MeOH)] i [MoO2(L2)(H2O)]·MeCN.As part of this diploma thesis, two hydrazone ligands, (H2L1) and (H2L2), derivatives of formic acid hydrazide and 2-hydroxybenzaldehyde or 2-hydroxy-5-nitrobenzaldehyde, were prepared. By reactions of [MoO2(acac)2] and corresponding hydrazone ligand, in 1 : 1 molar ratio, from corresponding solvent, molybdenum(VI) complex compounds were synthesized. Mononuclear complexes, [MoO2(L1)(MeOH)] and [MoO2(L2)(MeOH)] were synthesized from methanol, with pyridine. In reactions with acetonitrile one mononuclear complex compound, [MoO2(L1)(H2O)]·MeCN and two polynuclear complexes, [MoO2(L1)]n and [MoO2(L2)]n, were synthesized. Hydrazone ligands and complexes were characterized and analyzed by differential scanning calorimetry, infrared spectroscopy and thermogravimetric analysis. Molecular and crystal structures of the H2L1ligand and of [MoO2(L2)(MeOH)] and [MoO2(L2)(H2O)]·MeCN complexes were determined by the single crystal X-ray diffraction
The Relationship between Politics and Sport in Split during the Time of Mayor Ivo Tartaglia (1918-1928)
No full textOvim radom analiziran je i objašnjen odnos politike i sporta u Splitu od 1918. do 1928. godine. Odnos politike i sporta sagledavan je kroz državnu (unutarnju i vanjsku) i gradsku politiku te je objašnjeno kako su se društveni i politički problemi odražavali i utjecali na splitski sport od stvaranje jugoslavenske države 1918. godine do proglašenja Šestosiječanjske diktature. Također je analiziran i odnos sportskih institucija prema politici te odnos glavnog političkog lista u Splitu Novog doba prema sportu. Ovo razdoblje obilježeno je velikim promjenama u odnosu na razdoblje pod Austro-Ugarskom Monarhijom, što je rezultiralo osnivanjem klubova povezanih s nacionalnim identitetom i nacionalnom borbom, kao i onih kojih su imali jak socijalni karakter. Rezultati osnivanja takvih klubova bile su česte napetosti i sukobi među njima.This paper analyzes and explains the relationship between politics and sport in Split from 1918 to 1928. The relationship between politics and sport is examined through both state (internal and external) and city politics, and it is explained how social and political issues reflected and influenced Split’s sport from the creation of the Yugoslav state in 1918 to the proclamation of the January Sixth Dictatorship. The paper also analyzes the relationship of sports institutions to politics, as well as the stance of Split’s main political newspaper, Novo doba, towards sport. This period was marked by significant changes compared to the period under the Austro-Hungarian Empire, which resulted in the establishment of clubs linked to national identity and national struggle, as well as those with a strong social character. The outcome of founding such clubs was frequent tensions and conflicts between them
The influence of organic matter concentration and pH of the medium on the oral cavity bacteria replication
No full textBakterije usne šupljine kao što su Streptococcus mutans i Streptococcus sanguinis bitan su dio oralne mikrobiote. Bakterija S. mutans često se povezuje s nastankom karijesa. Zubni karijes jedna je od najčešćih bolesti u svijetu i predstavlja veliki problem u zdravstvu. U ovom radu bakterije su uzgajanje u tekućem hranjivom mediju, planktonskim načinom rasta. Ispitana je razlika umnažanja u tri koncentracije organske tvari (originalna, te razrjeđenja 1:1 i 1:10) i dvije vrijednosti pH (7.4 i 6.2), te pokazuju li ove dvije bakterije kompeticiju u kokulturi. Također, ispitivala se i tolerancija bakterija na određeni raspon vrijednosti pH u umjetnoj slini. Rezultati su pokazali da se umnažanje bakterija povećava s koncentracijom organske tvari. Pri najvećoj koncentraciji organske tvari bakterije se statistički značajno bolje umnažaju na pH 7.4 u odnosu na pH 6.2, dok pri nižim koncentracijama organske tvari nije bilo statistički značajne razlike. Obje bakterije se bolje umnažaju pri neutralnom pH (6.8-7.4) i bolje preživljavaju u alkalnoj sredini nego u kiseloj. Bakterija S. mutans bolje tolerira niski pH (pH ≤ 5.5) u odnosu na S. sanguinis. U planktonskom načinu rasta nije dokazana kompeticija između dvije ispitivane bakterije, a bakterija S. mutans je imala statistički značajno bolje rezultate umnažanja u kokulturi sa S. sanguinis.Oral bacteria Streptococcus mutans and Streptococcus sanguinis are an essential part of oral microbiota. Bacteria S. mutans is often associated with caries development. Caries is among the most common disease worldwide, representing a significant healthcare problem. In this research, bacteria were cultivated in Nutrient Broth to grow planktonically. The multiplication difference in three concentrations of organic matter (original and dilutions 1:1 and 1:10) and two pH values (7.4 and 6.2) were tested, and competition when grown together in co-culture was investigated. Tolerance to different pH values in artificial saliva was also tested. Results showed that the multiplication of these bacteria increases with the concentration of organic matter. At the highest concentration of organic matter bacteria reproduced statistically better at pH 7.4 compared to pH 6.2, while at lower concentrations there was no statistically significant difference. Both bacteria reproduce better at a neutral pH range (6.8-7.4) and survive better in an alkaline environment than in an acidic one. S. mutans was better at tolerating low pH (pH ≤ 5.5) than S. sanguinis. No competition was proven between these two bacteria, and S. mutans showed statistically better multiplication results in co-culture with S. sanguinis
Spectral sequences
No full textU ovom radu bavimo se spektralnim nizovima u području homološke algebre. Kako bismo učinkovito radili sa spektralnim nizovima, prvo uvodimo jednostavnije pojmove poput lančanog kompleksa, homoloških grupa, egzaktnih nizova, te tenzorskog i torzijskog produkta. Nakon toga definiramo dvostruke komplekse i dajemo primjere što shvaćamo kao važnu poveznicu između osnovnih rezultata homološke algebre i teorije spektralnih nizova. Tada definiramo spektralne nizove i njihovu konvergenciju te promatramo dva načina konstrukcije spektralnih nizova i njihovu povezanost. Osim toga, primjenjujemo spektralne nizove na dvostrukim kompleksima uključujući prethodno navedene konkretne primjerima iz homološke algebre i algebarske topologije.
Naposljetku, primjenjujemo teoriju spektralnih nizova u topologiji. Definiramo singularnu homologiju te singularnu homologiju i kohomologiju s koeficijentima te na njima primjenjujemo prethodno promatrane tvrdnje iz homološke algebre. Zatim definiramo fibracije i CW-komplekse kako bismo mogli definirati i promatrati Leray-Serreov spektralni niz i njegove primjene u algebarskoj topologiji.In this thesis, we are working with spectral sequences in the field of homological algebra. In order to efficiently work with spectral sequences, we first inroduce simpler terms such as chain complexes, homology groups, exact sequences, tensor product and torsion product. Afterwards, we define double complexes and give examples which we realize as an important link between more general homological algebra and spectral sequence theory. Then we define spectral sequences, their convergence and we observe two ways of constructing a spectral sequences and their connection, Other than that, we apply spectral sequences to double complexes including previously introduced examples from homological algebra and algebraic topology.
In the end, we apply spectral sequences in topology. We define singular homology, then singular homology and cohomology with coefficients, on which we apply previously obeserved propositions from homological algebra. After that, we define fibrations and CW-complexes in order to define and observe the Leray-Serre sequences and its applications in algebraic topology
Classical and quantum aspects of spacetime singularities
No full textZa prostorvrijeme kažemo da je singularno ako su neki njegovi geodezici nepotpuni i neproduljivi ili ako je neka od invarijanti zakrivljenosti neomeđena. Roger Penrose i Stephen W. Hawking su u 1960-ima pokazali nizom teorema pod kojim pretpostavkama je formiranje prostornovremenskog singulariteta neminovno prilikom gravitacijskog kolapsa materije. Nešto kasnije, Gary T. Horowitz i Donald Marolf su 1995. godine pokazali da neke kvantne probe ipak mogu imati regularno ponašanje na pozadini singularnog prostorvremena. U ovom radu obrađeni su klasični aspekti (teoremi o singularitetima) i kvantni aspekti (analiza kvantnih proba) prostornovremenskih singulariteta. Uvedena su dva formalizma za analizu ove problematike, samoadjungiranost odgovarajućih operatora, primarno za proučavanje hipoteze kozmičke cenzure; te Schrödingerova funkcionalna slika kvantne teorije polja, za proučavanje singulariteta zaštićenih horizontima.We say that spacetime is singular if some of its geodesics are incomplete and unextendable or if some of the curvature invariants are unbounded. In the 1960s, Roger Penrose and Stephen W. Hawking showed with a series of theorems under such assumptions that the formation of a spacetime singularity is inevitable during the gravitational collapse of matter. A little later, Gary T. Horowitz and Donald Marolf showed in 1995 that some quantum probes can still exhibit regular behaviour on the background of singular spacetime. In this paper, classical aspects (singularity theorems) and quantum aspects (quantum probe analysis) of spatiotemporal singularities will be analyzed. Two formalisms are introduced for dealing with this issue, the self-adjointness of corresponding operators, primarily for studying the cosmic censorship hypothesis; and the Schrödinger functional picture of quantum field theory, for studying singularities protected by horizons
Ultraviolet radiation mutational signatures in human uveal and skin melanoma
No full textMelanomi uvee i kože su dva različita tumorska tipa koja nastaju iz melanocita, stanica odgovornih za sintezu pigmenta melanina. Iako dijele zajedničku ishodišnu stanicu tumora, različiti egzogeni i endogeni čimbenici uzrokuju specifične obrasce mutacija koje nazivamo mutacijskim potpisima. Cilj ovog istraživanja je okarakterizirati i usporediti mutacije i mutacijske potpise prisutne u melanomima uvee i kože s naglaskom na mutacije u genima biomarkerima. Analizirane mutacije dobivene su sekvenciranjem cijelih eksoma 80 pacijenata melenoma uvee i 468 pacijenata melanoma kože, javno dostupnih u TCGA bazi podataka. Mutacijski potpisi pozvani su “refitting”-metodom potpisa COSMIC. Fisherov test primijenjen je za analizu diferencijalno mutiranih gena i biomarkera između melanoma, a Mann-Whitney U test i jednostrani jednoproporcijski Z-test za testiranje povezanosti specifičnih mutacijskih potpisa s mutacijama u genima biomarkerima. Rezultati ukazuju na diferencijalne mutacijske profile oba melanoma, kao i na diferencijalne mutacijske procese uključene u mutagenezu melanoma. Dok u melanomu kože prevladavaju UV mutacijski potpisi (SBS7b i SBS7a) oni su slabo zastupljeni u melanomu uvee. UV zračenje pokazalo se odgovornim za nastanak pokretačkih mutacija u biomarkerima BRAF, NRAS i CDKN2A melanoma kože, dok su za mutagenezu biomarkera melanoma uvee odgovorni drugi mutacijski procesi poput potpisa aristolohične kiseline SBS22 odgovornog za mutagenezu GNA11.Uveal and skin melanoma are two distinct tumor types arising from melanocytes, cells producing melanin pigment. Despite their common cell of origin, different exogenous and endogenous factors lead to specific mutational patterns known as mutational signatures. This research aims to characterize and compare the mutations and mutational signatures in uveal and skin melanoma, focusing on the mutations in the biomarker genes. The analysis examined the whole exome sequencing data of 80 uveal melanoma patients and 468 skin melanoma patients, publicly available in the TCGA database. Mutational signatures were called using the COSMIC signature refitting method. Fisher’s test was applied to analyze the differentially mutated genes and biomarkers between the melanomas, and the Mann-Whitney U test and one-tailed One-Proportion Z-Test to test the correlation between the specific mutational signatures and biomarker mutations. The results indicate differential mutational profiles of the melanomas, as well as differential mutational processes involved in melanoma mutagenesis. While UV mutational signatures (SBS7b and SBS7a) are predominant in skin melanoma, they are poorly represented in uveal melanoma. UV radiation seems to be responsible for driver mutations in the BRAF, NRAS, and CDKN2A biomarkers in skin melanoma, while other mutational processes are responsible for mutagenesis of uveal melanoma biomarkers, such as aristolochic acid signature SBS22 for GNA11 mutagenesis
Spatio-temporal dynamics of dipteran (Diptera, Insecta) assemblages of intermittent karstic rivers in the Mediterranean
No full textPovremene tekućice su složeni slatkovodni sustavi u kojima voda teče sezonski. Dominantan su tip tekućih slatkovodnih staništa na Zemlji, posebice u polusuhim regijama svijeta. Cilj ovog diplomskog rada je istražiti zajednice dvokrilaca u lotičkoj i lentičkoj fazi triju krških povremenih mediteranskih rijeka na području Hrvatske – Čikole, Krčića i Miljašić Jaruge. Uzorci su sakupljeni pomoću Surber mreže i izmjereni su i fizikalno-kemijski čimbenici vode. Jedinke dvokrilaca su determinirane do razine porodice. Ukupno je zabilježeno devet porodica dvokrilaca u lotičkoj fazi i sedam porodica u lentičkoj fazi. Promjenom hidroloških faza istraživanih povremenih rijeka, došlo je do promjene u vrijednostima fizikalno-kemijskih čimbenika vode, koja je praćena i promjenom parametara zajednica dvokrilaca. U obje hidrološke faze, jedinkama najbrojnija porodica bila je Chironomidae zbog njihove mogućnosti prilagodbe na promjenjive uvjete okoliša. Parametri zajednice dvokrilaca nisu se značajno razlikovali u lotičkoj fazi istraživanih tekućica. No, u rijeci Čikoli zabilježen je najveći broj porodica zbog najveće heterogenosti staništa, dok je najmanji broj porodica i jedinki zabilježen u antropogeno utjecanoj Miljašić Jarugi. Tijekom lentičke faze, značajno najveća brojnost jedinki dvokrilaca zabilježena je u lokvicama rijeke Krčić, vjerojatno zbog najniže temperature i električne provodljivosti vode. U obje hidrološke faze, zajednice dvokrilaca su pozitivno korelirane s temperaturom i električnom provodljivosti vode.Intermittent rivers are complex freshwater ecosystems characterized by seasonal interchange of dry and wet hydrological phases. They are the dominant type of running freshwater habitats, especially in semi-arid regions of the world. The aim of this thesis was to investigate Dipteran assemblages in the lotic and lentic phases of three karst intermittent Mediterranean rivers in Croatia – Čikola, Krčić and Miljašić Jaruga Rivers. Dipteran larvae were sampled with Surber net and physico-chemical water properites were measured. Dipteran specimens were identified to the family level. A total of nine and seven dipteran families was recorded in lotic and lentic phase of the three rivers, respectively. The change of hydrological phases of the studied intermittent rivers resulted in differences in the physico-chemical water properties, followed by changes in the Diptera assemblage parameters. In both hydrological phases, the Chironomidae family was the most abundant due to their adaptability to changing environmental conditions. Dipteran assemblage parameters did not significantly differ among the rivers during their lotic phase. However, in the Čikola River, the highest number of families was recorded due to the highest habitat heterogenity, while the lowest number of families and individuals were observed in the anthropogenically altered Miljašić Jaruga River. During the lentic phase, a significantly higher abundance of dipteran individuals was recorded in the pools of the Krčić River, likely due to the lowest water temperature and electrical conductivity. In both hydrological phases, dipteran assemblages were positively correlated with water temperature and electrical conductivity
The effect of the probiotic strain Lactobacillus sp. and its exopolysaccharides on the inflammatory process in the intestine of C57BL/6J mouse
No full textUlcerozni kolitis je kronična upala debelog crijeva koja zahvaća sluznicu. Ulcerozni kolitis
obilježen je smanjenjem tjelesne težine, proljevom, krvavom stolicom, patohistološkim
promjenama na sluznici crijeva te različitim patofiziološkim procesima kao što je kronična upala,
oksidativni stres, stres endoplazmatskog retikuluma. Budući da je jedan od glavnih čimbenika ove
bolesti disbioza, odnosno smanjena raznolikost bakterija u crijevima, danas se kao mogući pristup
liječenja ulceroznog kolitisa istražuje obrada probioticima. Cilj ovog istraživanja bio je utvrditi
kakav utjecaj ima probiotički soj Limosilactobacillus fermentum i njegovi egzopolisaharidi na
dekstran natrij sulfatom (DSS) inducirani kolitis kod miševa soja C57BL/6J. Indeks razvoja kolitisa
praćen je mjerenjem gubitka težine, kozistencije stolice i krvarenja, a posljedice bolesti analizom
hematoloških, histoloških i molekularnih odrednica metodom kvantitativne lančane reakcije
polimerazom (qPCR). Rezultati ukazuju na djelomočno pozitivan učinak probiotičkog soja
Limosilactobacillus fermentum i njegovi egzopolisaharida na DSS-inducirani kolitis miševa soja
C57BL/6J kroz smanjenu razinu upale i krvarenja te regeneraciju tkiva sluzniceUlcerative colitis is a chronic inflammation of the large intestine restricted to the mucosa.
Ulcerative colitis is characterized by weight loss, diarrhea, bloody stools, pathohistological
changes in the intestinal mucosa and various pathophysiological processes such as chronic
inflammation, oxidative stress, and endoplasmic reticulum stress. Since one of the main factors of
this disease is dysbiosis, which is a reduced diversity of bacteria in the gut, today the use of
probiotics is being investigated as a potential approach for treating ulcerative colitis. The aim of
this research was to determine the impact of the probiotic strain Limosilactobacillus fermentum
and its exopolysaccharides on dextran sodium sulfate (DSS) induced colitis in C57BL/6J mouse.
The colitis activity index was monitored through measurements of weight loss, stool consistency,
and bleeding, while the disease outcomes were analyzed using hematological, histological, and
molecular markers through quantitative polymerase chain reaction (qPCR). The results indicate a
partially positive effect of the probiotic strain Limosilactobacillus fermentum and its
exopolysaccharides on DSS-induced colitis in C57BL/6J mice, manifested by reduced
inflammation and bleeding, as well as mucosal tissue regeneration