Croatian Digital Thesis Repository
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Analysis of the Influence of the Interlayer on the Behaviour of Laminated Glass Beams Exposed to Bending : Master's Thesis
No full textOvaj diplomski rad analizira utjecaj izbora međusloja kod laminiranih staklenih nosača izloženih savijanju. U prvom dijelu rada opisani su različiti međuslojevi koji se koriste kod ovakvih nosača te navedene osnovne materijalne karakteristike potrebne za proračun. Proveden je analitički proračun laminiranih nosača izloženih savijanju prema prEN16612, te izvršena numerička analiza laminiranih nosača izloženih savijanju (fourpoint bending test) varirajući međuslojeve. Na kraju su dobiveni analitički i numerički rezultati uspoređeni s eksperimentalnim istraživanjima objavljenim u literaturi, te formulirani zaključci.This thesis analyses the influence of the interlayer choice in laminated glass beams exposed to bending. The first part of the paper describes the different interlayers used in such supports and lists the basic material characteristics required for the calculation. Analytical calculation of laminated beams exposed to bending according to prEN16612 was performed, and numerical analysis of laminated beams exposed to bending (fourpoint bending test) was performed, varying the interlayers. Finally, analytical and numerical results were obtained compared with experimental research published in the literature, and conclusions were formulated
The effect of cytokines TNF-alpha and IFN-gamma on REL, CXCL10 and PD-L1 gene expression in Farage and U2940 cell lines
No full textStanice imunosnog sustava posredstvom specifičnih receptora i signalnih molekula citokina reguliraju i aktiviraju imunosni odgovor. Aktivacijom raznih signalnih putova dolazi do aktivacije i diferencijacije imunosnih stanica u zrele i efektorske oblike. Faktor tumorske nekroze alfa (TNF-α, od engl. tumour necrosis factor) aktivira signalni put NF-κB, regulira ekspresiju posredničkih molekula i imunosnim stanicama omogućuje migraciju. Interferon gama (IFN-γ) aktivira signalni put JAK-STAT, utječe na ekspresiju kemokina i molekula glavnog sustava tkivne podudarnosti (MHC, od engl. major histocompatibility complex) te na aktivaciju imunosnih stanica. Procesi diferencijacije imunosne stanice čine tolerantnijima prema nakupljanju promjena u genomu i nepravilnoj transformaciji, koja može dovesti do nastanka limfoma. Primarni medijastinalni B-stanični limfom (PMBL) spada u skupinu ne-Hodgkinovih limfoma (NHL), a nastaje od B-limfocita smještenih u medijastinumu. U ovom radu istražen je utjecaj citokina TNF-α i IFN-γ na razinu ekspresije gena REL, CXCL10 i PDL1 u modelnim staničnim linijama. Gen REL kodira protein c-Rel, transkripcijski faktor signalnog puta NF-κB. Gen CXCL10 kodira istoimeni kemokin. Gen PDL1 kodira protein koji sudjeluje u mehanizmu koji regulira odgovor T-limfocita. Tretman citokinom IFN-γ povećavao je ekspresiju gena CXCL10 kod obje stanične linije, a ekspresiju gena PDL1 samo kod jedne stanične linije. Tretmani citokinom TNF-α pokazali su mješovite rezultate između staničnih linija za gen CXCL10 te većinom uzrokovali smanjenje ekspresije gena PDL1 i REL. Varijabilnost ekspresije istraživanih gena ukazuje na veliku heterogenost primarnog medijastinalnog limfoma.Immune cells regulate the immune response by interacting with specific receptors expressed on their surface and by secreting cytokines. Tumour necrosis factor alpha (TNF-α) activates the NF-κB signalling pathway, regulates the expression of mediators and enables the migration of immune cells. Interferon-gamma (IFN-γ) activates the JAK-STAT signalling pathway and influences the expression of chemokines and proteins of the major histocompatibility complex (MHC) and the activation of immune cells. The processes that immune cells undergo during their differentiation can contribute to abnormal transformations and the formation of lymphomas. Primary mediastinal large B-cell lymphoma (PMBL), a form of non-Hodgkin's lymphoma (NHL), arises from B-cells located in the mediastinum. The aim of this study was to investigate the effect of cytokines TNF-α and IFN-γ on the expression of REL, CXCL10 and PDL1 genes in PMBL model cell lines. The REL gene encodes the c-REL transcription factor of the NF-κB signalling pathway. The CXCL10 gene codes for a chemokine. The PDL1 gene codes for a protein that plays a decisive role in the regulatory mechanism of the T-cell immune response. IFN-γ caused an increase in CXCL10 gene expression in both cell lines and PDL1 gene expression in one cell line. TNF-α, on the other hand, showed ambiguous results for the CXCL10 gene and predominately caused a decrease in gene expression of PDL1 and REL genes. The variability of the expression of the investigated genes indicates the significant heterogeneity of primary mediastinal lymphoma
Expression profiles of rac1A, rac1B and rac1C genes in single and double rac1 mutants in Dictyostelium discoideum cells
No full textProteini Rac1A, Rac1B i Rac1C iz amebe Dictyostelium discoideum pripadaju porodici GTPaza Rho i reguliraju aktinski citoskelet. Zbog velike homologije među njima i nepostojanja značajnih promjena u fenotipu jednostrukih mutanata, u literaturi se uvriježilo mišljenje da ovi proteini imaju preklapajuće funkcije. Međutim, karakterizacija mutanata pojedinačno deficijentnih za gene rac1 konstruiranih u Laboratoriju za staničnu dinamiku Instituta Ruđer Bošković u Zagrebu pokazala je da stanice rac1A- imaju defekte tijekom vegetativnog rasta. Nadalje, u odsutnosti proteina Rac1A opaženo je veliko statistički značajno povećanje ekspresije gena rac1B i rac1C. Kako bih ispitala dolazi li do povećanja ekspresije preostalog gena rac1 u dvostrukim mutantima deficijentnima za gen rac1A, u stanicama rac1A- uklonila sam gene rac1B i rac1C. Uklanjanje gena potvrdila sam metodom PCR i Southernovom metodom otiska. Potom sam metodom qPCR analizirala ekspresiju sva tri gena rac1 u stanicama divljeg tipa i mutanata. U stanicama rac1A-/rac1B- i rac1A-/rac1C- ekspresija preostalog gena rac1 ostala je značajno viša u odnosu na stanice divljeg tipa. Također opazila sam promjene fenotipa specifične za stanice rac1A-/rac1B-. Ovi rezultati pokazuju da povećana ekspresija gena rac1B i/ili rac1C ne može u potpunosti nadomijestiti funkciju proteina Rac1A, što ukazuje na to da proteini Rac1, osim preklapajućih, imaju i specifične uloge u stanici.The D. discoideum proteins Rac1A, Rac1B and Rac1C are GTPases of the Rho family that are involved in the regulation of the actin cytoskeleton. Due to the high homology between them, it is assumed that they have overlapping functions. Furthermore, cells lacking the single Rac1 protein showed no significant phenotypic changes. However, analyzes of rac1A-, rac1B- and rac1C- mutants produced in the Laboratory of cell dynamics (RBI Zagreb) revealed that rac1A- cells are defective during vegetative growth. Moreover, rac1B and rac1C expression was significantly increased in the absence of Rac1A. To analyze the expression profile of double mutants lacking Rac1A, I generated rac1A-/rac1B- and rac1A-/rac1C- cells. After confirming the deletion of rac1B and rac1C genes in rac1A- cells by PCR and Southern blot, I analyzed the expression of the three rac1 genes by qPCR. Relative quantification of expression showed that in both rac1A-/rac1B- and rac1A-/rac1C- double mutants, the expression of the third rac1 gene remains strikingly elevated. In addition, preliminary observations indicate phenotypic changes specific to the rac1A-/rac1B- genotype. Therefore, overexpression of rac1B and/or rac1C cannot fully rescue the phenotype of mutants lacking Rac1A and Rac1 GTPases not only have overlapping functions but also perform specific roles in the cell
Effect of microplastics treated with heavy metals on physiological and biochemical stress parameters in duckweed (Lemna minor)
No full textMikroplastika (MP) je kompleksno onečišćivalo te je sveprisutna u morskim, slatkovodnim i kopnenim ekosustavima. Pod utjecajem abiotičkih i biotičkih čimbenika njezina se svojstva mijenjaju, a time i potencijalna toksičnost za okoliš. U ovom radu je istražen utjecaj čiste MP (smjesa polietilena, polistirena, polipropilena i gume), kao i MP tretirane smjesom teških metala (olovo, cink i bakar) na vodenu leću (Lemna minor L.) putem Lemna testa i različitih fizioloških i biokemijskih pokazatelja stresa (sadržaj fotosintetskih pigmenata, karbonila i malondialdehida, te aktivnost antioksidacijskih enzima). Rezultati su pokazali da dolazi do otpuštanja metala s površine MP u hranjivu podlogu. Utvrđeno je nakupljanje Zn i Cu u vodenoj leći izloženoj najvećoj koncentraciji MP. Sedmodnevno izlaganje vodene leće česticama čiste MP ili MP s adsorbiranim metalima nije bitno utjecalo na rast vodene leće, izuzev čiste MP u koncentraciji 100 i 1000 čestica/L. Mikroplastika je izazvala promjene u aktivnosti antioksidacijskih enzima, no nije utvrđena lipidna peroksidacija ni oksidacijsko oštećenje proteina. Zamijećena je jača adsorpcija čestica MP (uglavnom polipropilena) na listićima vodene leće. Na temelju dobivenih rezultata može se zaključiti da je vodena leća pogodna za fitoremedijaciju čestica MP.Microplastics (MP) are very complex pollutants that are ubiquitous in the marine, freshwater and terrestrial enviroments. MP is affected by various biotic and abiotic factors that can change its properties and potential toxicity for the environment. In the present study, the effect of pristine MP (mixture of polyethylene, polypropylene, polystyrene and tyre wear particles) and MP treated with heavy metals (lead, copper, zinc) on duckweed (Lemna minor L.) has been evaluated using Lemna test and various physiological and biochemical stress parameters (photosynthetic pigments, carbonyls and malondialdehide as well as activity of antioxidant enzymes). The results showed that metals leached out from MP into the Steinberg medium. Metals Zn and Cu accumulated in duckweed exposed to the highest concentration of MP. Pristine MP and MP treated with heavy metals did not significantly affect the growth rate of Lemna minor, except pristine MP at higher concentration (100 and 1000 particles / L). Microplastics caused modulation of antioxidant enzyme activities, but lipid peroxidation and oxidative damage to proteins was not observed. Furthermore, MP (polypropylene) was found to strongly adsorb on duckweed fronds. Based on the obtained results, it can be concluded that the Lemna minor is suitable for the phytoremediation of MP
Development and validation of ultra-performance liquid chromatography method for the analysis of cinnarizine degradation products
No full textKemijska stabilnost aktivnih farmaceutskih sastojaka utječe na sigurnost i učinkovitost lijekova. U sklopu ovog diplomskog rada razvijena je, a zatim i validirana stabilitetno-indikativna metoda tekućinske kromatografije ultravisoke djelotvornosti uz detektor s diodnim nizom za praćenje kemijske stabilnosti cinarizina. Kako bi se razvila prikladna stabilitetno-indikativna analitička metoda najprije je provedena prisilna razgradnja na uzorcima cinarizina. Provedena je razgradnja pod utjecajem hidrolitičkih uvjeta (u neutralnom, kiselom i bazičnom mediju) pri temperaturi od 80 °C, razgradnja pod utjecajem oksidativnih uvjeta te fotolitička razgradnja cinarizina u otopini pri sobnoj temperaturi. Strukturna karakterizacija razgradnih produkata provedena je korištenjem spregnutog sustava tekućinska kromatografija ultravisoke djelotovornosti – spektrometrija masa visokog razlučivanja, uz eksperimente tandemne spektrometrije masa na ionima od interesa pri različitim vrijednostima kolizijskih potencijala.The chemical stability of active pharmaceutical ingredients affects the safety and effectiveness of drugs. As part of this thesis, a stability-indicative method of ultra-high efficiency liquid chromatography with a diode array detector for monitoring the chemical stability of cinnarizine was developed and then validated. To develop a suitable stability-indicative analytical method, forced degradation was performed on cinnarizine samples. Degradation under the influence of hydrolytic conditions (in neutral, acidic, and basic media) at a temperature of 80 °C, degradation under the influence of oxidative conditions and photolytic degradation of cinnarizine in solution at room temperature were carried out. Structural characterization of degradation products was carried out using a coupled system of ultra-high performance liquid chromatography – high resolution mass spectrometry, with tandem mass spectrometry experiments on ions of interest at different values of collision potentials
Višestruko istovremeno dokiranje malih molekula u aktivno mjesto butirilkolinesteraze primjenom dubokog pojačanog učenja
No full textCholinesterase inhibitors are often used in treating Alzheimer’s disease. Molecular docking
represents an important tool in the design of novel inhibitors. In this study, a multicomponent
quantum chemical Monte Carlo semi flexible molecular docking of four selected components of
the Ugi reaction was performed inside the active site of butyrylcholinesterase (BChE). The IC 50
value of compounds was evaluated, and artificial neural networks (ANNs) were trained by deep
reinforcement learning for two of them, using results from docking. Even though components
alone do not inhibit BChE significantly, formaldehyde and benzylamine can be used jointly for
the design of novel drugs because they bind closely to the enzyme’s catalytic triad. In addition,
the advantage of using the three component Ugi reaction is highlighted. Finally, ANN was shown
to be successful in representing a potential energy surface of docking simulations. O btained ANN
can be used as a scoring function for future dockings, with significantly shorter calculation time.U liječenju Alzheimerove bolesti često se koriste inhibitori kolinesteraza. Molekularno dokiranje važan je alat u dizajnu novih inhibitora, a u ovome je radu unutar aktivnog mjesta butirilkolinesteraze (BChE) provedeno multikomponentno kvantno-kemijsko Monte Carlo polufleksibilno dokiranje četiriju komponenata Ugijeve reakcije. Određene su im i vrijednosti IC50 te su za dvije od njih istrenirane umjetne neuronske mreže (ANN) primjenom dubokog pojačanog učenja za opis rezultata dokiranja. Iako zasebne molekule ne inhibiraju značajno BChE, formaldehid i benzilamin zajedno mogu poslužiti u dizajnu novih lijekova jer se vežu u blizini katalitičke trijade enzima. Uz to, istaknuta je prednost uporabe trokomponentne Ugijeve reakcije. Naposlijetku, pokazano je da se ANN može uspješno koristiti u reprezentaciji plohe potencijalne energije dokiranja. Dobivena mreža može ubuduće poslužiti kao funkcija bodovanja, uz znatno kraće trajanje proračuna
Traffic Analysis of the Award-winning Works of the Survey Competition for the Creation of a Conceptual Urban Solution for the East Coast City Project in Split : Master's Thesis
No full textDiplomski rad analizira primjenu tehnika prometnog inženjerstva u kontekstu urbanističkog projekta Istočne obale grada Splita. Cilj rada je proučiti predložena prometna rješenja i usporediti ih s postojećim stanjem, s fokusom na analizu kvalitete prometnih tokova. Za tu svrhu koristit će se softverski alat SIDRA, koji omogućuje simulaciju prometnog toka i pruža podatke o kapacitetu raskrižja, vremenima zadržavanja vozila i drugim relevantnim parametrima. Kroz analizu će se utvrditi prosječno zakašnjenje vozila, stupanj zasićenosti i razina usluge što će ukazati na kritična mjesta i moguće probleme u prometu na obuhvaćenom području.The master's thesis analyzes the application of traffic engineering techniques in the context of the urban project of the Eastern Coast of Split. The aim of the study is to examine the proposed traffic solutions and compare them with the existing conditions, with a focus on analyzing the quality of traffic flow. For this purpose, the SIDRA software tool will be used, which allows for traffic flow simulation and provides data on intersection capacity, vehicle delay times, and other relevant parameters. Through the analysis, average vehicle delay, degree of saturation, and level of service will be determined, indicating critical areas and potential traffic issues within the studied area
Velika sportska događanja kao pokretač razvoja turizma destinacija
No full textSportska događanja postaju sve popularnija. Tijekom posljednjeg desetljeća broj posjećenosti na sportskim događanjima se drastično povećao. Ljudi su spremni proputovati puno kilometara samo kako bi prisustvovali na njima. Upravljanje sportskim događanjima može se povezati s turizmom jer obje djelatnosti proizlaze iz želje pojedinca za kvalitetno ispunjenim slobodnim vremenom i zadovoljavanjem određenih potreba. U radu su navedene brojne studije i istraživanja vezane za sportski turizam i velika sportska događanja poput Svjetskog prvenstva ili Olimpijskih igara
Improvement of processes in the production of electronic components
No full textU ovom radu predstavljena je i analizirana proizvodnja elektroničkih pločica na proizvodnoj liniji u tvrtki Smart Sense d.o.o. Prije provedene analize razrađena je struktura ključnih pokazatelja uspješnosti te je naposlijetku odabrano nekoliko njih koji su kontinuirano mjereni. Nakon mjerenja analizirana je pojava zastoja, kako njihove vrste tako i učestalosti pojavljivanja, a zastoji su zatim podijeljeni u šest velikih gubitaka. Korištenjem alata Lean metodologije predložena su poboljšanja za eliminaciju ili skraćivanje zastoja te za potencijalno uklanjanje gubitaka. Neka od poboljšanja su i provedena, dok su neka ostala prisutna isključivo kao prijedlozi. Potom je ponovno provedeno mjerenje ključnih pokazatelja uspješnosti te su doneseni zaključci o uspješnosti provedenih poboljšanja. Naposlijetku je raspravljeno potencijalno uvođenje digitalnog sustava za praćenje ključnih pokazatelja uspješnosti kroz analizu jednog gotovog rješenja dostupnog na tržištu i kroz razmatranje mogućnosti razvoja vlastitog rješenja.This thesis presents and analyzes the production of electronic boards on te production line in the company Smart Sense d.o.o. Before the analysis was carried out, the structure of key performance indicators was elaborated, and finally several of them were selected and continuously measured. After the measurements, the occurence of jams and losses was analyzed with both their types and frequency of occurrence, and they were then divided into six big losses. Using Lean methodology tools, improvements were proposed to eliminate or shorten downtime and potentially to eliminate losses. Some of the improvements were eliminated, while some remained present only as suggestions. After that, the key performance indicators were measured again and conclusions were drawn on the success of the implemented improvements. Finally, the implementation of KPI dashboard was discussed through the analysis of a ready-made solution available on the market and through overview of the possibility of developing an in-house solution
Computational analysis of the correlation between vaginal microbiota and HPV status in the general female population
No full textIako zauzima oko 9% mikrobioma žena, mikrobiom rodnice važan je za zdravlje ženskog reproduktivnog sustava. Zdrav mikrobiom rodnice karakterizira visoka zastupljenost bakterijskog roda Lactobacillus koji, osim snižavanjem pH, rodnicu često štiti proizvodnjom vodikova peroksida (H2O2). Mikrobiom se može proučavati metodama uzgoja bakterija, ali je na taj način nemoguće zabilježiti cjelokupnu mikrobnu bioraznolikost, niti je jednostavno proučavati ulogu, funkciju i interakciju mikrobioma s ogranizmom domaćinom. Umjesto toga, zahvaljujući napretku visokoprotočnog sekvenciranja, koristi se metagenomika. Njome se mikrobiom može proučavati izravno, bez uzgoja pojedinih vrsta ili sojeva, čime se, uz pripadajuću bioinformatičku analizu, mikrobiom može bolje taksonomski opisati, a omogućava se i njegovo funkcijsko opisivanje, primjerice analizom učestalosti upotrebe kodona. Pomoću dobivenih izvornih očitanja visokoprotočnog sekvenciranja metagenoma 10 uzoraka prikupljenih tijekom dobrovoljnog davanja brisa rodnice u svrhu testiranja na HPV, odredio sam taksonomski sastav mikrobioma unutar kraljevstva bakterija na svim taksonomskim razinama. Na temelju tih rezultata uzorke sam grupirao, te sam odredio gene i metaboličke puteve kojima su pojedine skupine uzoraka obogaćene. U konačnici sam ustanovio da postoje statistički značajne razlike između pojedinih skupina uzoraka u skladu s dosadašnjom literaturom, ali nisam mogao odrediti koje taksonomske skupine ili koja funkcija mikrobioma je povezana s povećanom zarazom HPV-a.Although it occupies only about 9% of female's microbiome, microbiome of the uterus is important for the health of the female reproductive system. A healthy uterine microbiome is characterised by high abundance of bacterial genus Lactobacillus. The genus is protecting uterus by lowering its pH and producing hydrogen peroxide. Microbiome can be studied by cultivation method, which is unable to cover much of a microbial diversity and it is not providing easy functional analysis. Metagenomic is an alternative method enabled by high-throughput sequencing. It can be used for a direct taxonomic characterization of a microbiome, without prior cultivation, and it facilitates functional analysis of codon bias, by applying proper bioinformatic tools. I determined taxonomic composition for kingdom of Bacteria for all taxonomic levels to group 10 samples taken from volunteers that gave the samples from uterus to test them for the presence of HPV infection. Additionally, I determined genes and metabolic pathways for which the samples were enriched. Finally, I found that certain metadata is statistically significantly different between the samples in accordiance with current literature, but I could not determine which taxonomic units or function of microbiom are in correlation with HPV infection