Croatian Digital Thesis Repository
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Heavy metals in formulated dietary supplements for the treatment of inflammatory bowel diseases
No full textUpalne bolesti crijeva su teške bolesti s nuspojavama koje utječu na svakodnevni život pacijenata koji od njih boluju. Mnogi uz standardnu farmakoterapiju uzimaju i razne dodatke prehrani. Među njima su i biljni pripravci kurkume, justicije i indijskog tamjanovca koji se koriste za ublažavanje simptoma upalnih bolesti crijeva. Osim bioaktivnih molekula koje se prirodno nalaze u ovim biljkama i koje pokazuju farmakološki učinak, mogu se naći i razna onečišćenja kao naprimjer teški metali.. Teški metali nemaju fiziološku funkciju u ljudskom tijelu i osim toga imaju potencijal biti iznimno toksični. U ovom radu se određivao sadržaj olova, arsena i cinka u 12 dodatak prehrani s ciljem procjene sigurnosti njihove primjene.. Koncentracija metala je određena atomskom apsorpcijskom spektrometrijom grafitnom tehnikom nakon prvotne mikrovalne digestije uzoraka. Izračunata je količina teških metala koja bi se unijela u jednoj dozi i dnevno prateći upute proizvođača i od 12 uzoraka jedan od njih prelazi dozvoljeni dnevni unos za olovo prema ICH smjernicama. U pripravcima su dokazane varijabilne koncentracije teških metala što ukazuje na potrebu temeljite kontrole sigurnosti ovakvih dodataka prehrani.Inflammatory bowel diseases are crippling diseases that have a severe impact on the everyday life of its patients. Many such patients take various dietary supplements in addition to their standard pharmacotherapy. Among them exist herbal supplements based on turmeric, green chiretta and Indian frankincense which are used to alleviate the symptoms of inflammatory bowel diseases. In addition to the bioactive molecules that are naturally found in these plants and that show a pharmacological effect, various pollutants can be found, such as heavy metals. Heavy metals have no physiological function in the human body and, in addition, have the potential to be extremely toxic. In this study, the content of lead, arsenic and zinc in 12 dietary supplements was determined with the aim of assessing the safety of their use. Metal concentration was determined by atomic absorption spectrometry using the graphite technique after initial microwave digestion of the samples. The amount of heavy metals that would be ingested in a singular and daily dose following the recommended intake by the manufacturer was calculated, and out of 12 samples, one of them exceeded the permitted daily intake for lead according to ICH guidelines. Variable concentrations of heavy metals have been proven in the preparations, which indicates the need for thorough control of the safety of such dietary supplements
Vision face filters for augmentation and manipulation
No full textU ovom radu obrađena je primjena vizijskih filtera za lice u kontekstu augmentacije i manipulacije u stvarnom vremenu. Rad se fokusira na teorijsku osnovu računalnog vida i strojnog učenja, s posebnim naglaskom na metode prepoznavanja i praćenja značajki lica. Detaljno su opisani različiti tipovi filtera, uključujući filtere za zamjenu lica i augmentaciju dodavanjem virtualnih elemenata. Prikazani su ključni koncepti poput prepoznavanja lica, Haar kaskada, te detekcije karakterističnih oznaka lica pomoću DLIB biblioteke. Eksperimentalni dio rada uključuje implementaciju i testiranje razvijenih filtera s ciljem evaluacije performansi i identificiranja potencijalnih ograničenja. Rad također nudi prijedloge za unaprjeđenje sustava kako bi se smanjila latencija i povećala točnost.The application of facial vision filters in the context of real-time augmentation and manipulation is discussed in this paper. The work focuses on the theoretical foundations of computer vision and machine learning, with particular emphasis on methods of facial feature recognition and tracking. Various types of filters are described in detail, including face swap filters and augmentation filters by adding virtual elements. Key concepts such as facial recognition, Haar cascades, and detection of facial landmarks using the DLIB library are presented. The experimental part of the paper includes the implementation and testing of the developed filters with the aim of evaluating performance and identifying potential limitations. The paper also offers suggestions for system improvements to reduce latency and increase accuracy
Knowledge management in company X
No full textU radu je analizirano upravljanje znanjem u Poduzeću X sa ciljem ispitivanja njegovih utjecaja
na različite aspekte organizacije. Koristeći korelacijsku analizu, utvrđeno je da ocjena metoda
upravljanja znanjem pozitivno korelira s osobnim razvojem zaposlenika i prijenosom znanja
među odjelima. Iako su ti odnosi značajni, ne postoji snažna povezanost između upravljanja
znanjem i skraćenja vremena isporuke proizvoda, kao ni između sustava i poticanja
inovativnosti. Deskriptivna statistika pokazuje da gotovo polovica zaposlenika sustav
upravljanja znanjem ne koristi redovito, što sugerira da postoji prostor za poboljšanje u
njegovoj integraciji u svakodnevne aktivnosti. Na temelju rezultata, hipoteza da sustav
upravljanja znanjem značajno smanjuje gubitak intelektualnog kapitala prilikom odlaska
ključnih zaposlenika je potvrđena, dok je hipoteza da poboljšava operativne aktivnosti i
skraćuje vrijeme isporuke djelomično potvrđena.The paper analyzes knowledge management in Company X with the aim of examining its
impact on various organizational aspects. Correlation analysis reveals that the assessment of
knowledge management methods positively correlates with employee personal development
and knowledge transfer between departments. Although these relationships are significant,
there is no strong link between knowledge management and reduction in delivery time or
between the system and innovation encouragement. Descriptive statistics indicate that nearly
half of the employees do not regularly use the knowledge management system, suggesting
room for improvement in its integration into daily activities. Based on the results, the
hypothesis that the knowledge management system significantly reduces the loss of
intellectual capital when key employees leave was confirmed, while the hypothesis that it
improves operational activities and reduces delivery time was partially confirmed
SPME-GC-MS analiza odabranih fotoinicijatora u papirnatim i kartonskim materijalima za pakiranje hrane
No full textMost food products are packaged. Paper is mainly used for this purpose, especially due to the increased awareness of the plastics impact on the environment. Due to its good printability, it is usually printed with UV inks. These contain photoinitiators, which have a low molecular weight and can be prone to migration. However, in order to comply with the framework regulation (EC) 1935/2004, printing inks must not release substances to the packaged food in quantities that could lead to undesirable changes. Therefore, this work focused on the development of a highly sensitive, selective and accurate SPME-GC-MS method for the determination of selected photoinitiators in paper and board food packaging materials. An internal standard method was used for quantification, so method is optimised to be less labour intensive and require little sample preparation time. Selected packaging materials from supermarkets were analysed and photoinitiators were found in some of them.Većina prehrambenih proizvoda je pakirana. U tu se svrhu uglavnom koristi papir, posebice zbog povećane svijesti o utjecaju plastike na okoliš. Zbog dobre mogućnosti ispisa većina ih se tiska UV-tintama. One sadrže fotoinicijatore koji su niske molekularne mase te su skloni migraciji. Kako bi bile usklađene s Uredbom (EZ) 1935/2004, tiskarske tinte ne smiju ispuštati tvari u pakiranu hranu u količinama koje bi mogle dovesti do neželjenih promjena. Stoga je cilj ovog rada razvoj vrlo osjetljive, selektivne i točne SPME-GC-MS metode za određivanje odabranih fotoinicijatora u papirnim i kartonskim materijalima za pakiranje hrane. Za kvantifikaciju je korištena interna standardna metoda, tako da je metoda optimizirana da bude manje radno intenzivna i zahtijeva malo vremena za pripremu uzorka. Analizirani su odabrani materijali za pakiranje iz supermarketa te su u nekima od njih pronađeni fotoinicijatori
Development of guidelines for the utilisation of topological optimisation in biologically inspired design
No full textBiološki nadahnuto konstruiranje temelji se na inspiraciji, učenju i oponašanju strategija iz prirode za rješavanje inženjerskih problema. U ovom radu predložena je metodologija za razvoj smjernica za primjenu topološke optimizacije u biološki nadahnutom konstruiranju. Inspiracija dolazi iz načina na koji biološke strukture prenose opterećenje, što je uzeto u obzir prilikom modeliranja geometrije i rubnih uvjeta u procesu topološke optimizacije. Korištenjem predložene metodologije razvijene su smjernice za osam biološki nadahnutih struktura, a zatim su predloženi koraci za primjenu tih smjernica u konstruiranju novih proizvoda. Praktična primjena koraka prikazana je i validirana kroz dvije studije slučaja, kreiranje koncepta biološki nadahnutog naplatka automobila i biološki nadahnutog stolca.Biologically inspired design is based on inspiration, learning, and mimicking strategies from nature to solve engineering problems. This paper proposes a methodology for developing guidelines for the utilisation of topology optimisation in biologically inspired design. The inspiration comes from the way biological structures transfer loads, which is considered when modelling geometry and boundary conditions in the topology optimisation process. Guidelines were developed for eight biologically inspired structures, followed by proposed steps for applying these guidelines in the design of new products. The practical application of these steps is demonstrated and validated through two case studies: the creation of a concept for a biologically inspired car rim and a biologically inspired chair
Reconstruction of the industrial refrigeration system
No full textU ovom radu je projektirano i proračunato rashladno postrojenje za skladištenje piletine i puretine u Zagrebu. Proračunata je rashladna komora dimenzija 47x23,5x4,4 m. Temperatura u komori iznosi 0 °C. U radu je proveden proračun toplinskog opterećenja komore, proračun i dimenzioniranje komponenti sustava, kao i komponente za upravljanje uljem, proračun i dizajn isparivača i kondenzatora te proračun količine punjenja radne tvari i kompresorskog ulja. Priložena je shema spajanja i automatske regulacije te dispozicijski crtež rashladnog agregata.In this thesis, a refrigeration plant for storage of chicken and turkey in Zagreb has been designed and calculated. The cooling chamber with dimensions 47x23,5x4,4 m has been calculated. The temperature maintained in the chamber is 0 °C. This thesis includes the calculation of heat load of chamber, the calculation and sizing of the system components, as well as the components for oil managment, the calculation of the quantitiy of refridgerant and compressor oil. A shematic of the connections and automatic regulation, as well as a layout drawing of the refridgeration unit, are also provide
The Quality of Bread Produced with a Mixture of Wheat Flour and Quercus rotundifolia Oak Acorn Flour
No full textZadatak ovog rada bio je ispitati utjecaj dodatka različitih omjera pšeničnog brašna i brašna žira hrasta Quercus rotundifolia (100:0, 80:20, 60:40, 40:60) na kvalitetu kruha. Provedena su probna laboratorijska pečenja i ispitivanje kvalitativnih svojstava kruha. Određen je specifični volumen i omjer visine i širine kruha, ispitan je teksturalni profil kruha te određena boja u CIELab. Provedena je i senzorska ocjena proizvedenih uzoraka kruha. Rezultati su pokazali da povećanjem udjela brašna žira raste čvrstoća kruha, dok specifični volumen, elastičnost i kohezivnost opadaju. Kruh sa 60 % brašna žira pokazao je najveću čvrstoću te najmanju elastičnost i specifični volumen. Dodavanje brašna žira uzrokovalo je tamniju boju sredine kruha, s povećanjem crvenih i žutih tonova. Senzorska prihvatljivost kruha s većim udjelom brašna žira (60 %) bila je značajno smanjena te se na temelju dobivenih rezultata može preporučiti njegova upotreba u količinama do 40 % kako bi se unaprijedila nutritivna vrijednost i funkcionalna svojstva kruha.The aim of this study was to examine the impact of adding different ratios of wheat flour and acorn flour from Quercus rotundifolia (100:0, 80:20, 60:40, 40:60) on bread quality. Laboratory test baking and evaluation of bread quality properties were conducted. The specific volume and height-to-width ratio of the bread were determined, the textural profile of the bread was examined, and the color in CIELab was measured. A sensory evaluation of the produced bread samples was also carried out. The results showed that increasing the proportion of acorn flour increased the firmness of the bread, while the specific volume, elasticity, and cohesiveness decreased. Bread with 60% acorn flour exhibited the highest firmness and the lowest elasticity and specific volume. Adding acorn flour caused a darker color in the bread crumb, with increased red and yellow tones. The sensory acceptability of bread with a higher proportion of acorn flour (60%) was significantly reduced. Based on the obtained results, it is recommended to use acorn flour in amounts up to 40% to enhance the nutritional value and functional properties of the bread
Crystal violet dye removal from aqueous solution by electrocoagulation : bachelor thesis
No full textUklanjanje boje Crystal Violet (CV) iz vodene otopine (4 ± 0.23 mg/L CV + 2 mg/L NaCl) procesom elektrokoagulacije (EK) provedeno je u dva smjera. U prvom slučaju promatran je utjecaj gustoće struje (0.016, 0.024 i 0.032 A/cm 2 ; pH = 3.2), dok je u drugom slučaju razmatran utjecaj početne pH vrijednosti (3.2, 5.5 i 7.0; i = 0.024 A/cm 2 ) na uklanjanje CV boje. Tijekom EK procesa, koji je trajao 50 minuta, promatrana je promjena pH, temperature, električne provodnosti te koncentracije CV boje. Učinkovitost uklanjanja CV boje EK procesom je izuzetno dobra. Pri tome, uklanjanje boje raste s vremenom trajanja procesa te porastom gustoće struje i porastom pH vrijednosti. Izuzetno dobri rezultati postignuti su primjenom najveće gustoće struje (potpuno uklanjanje nakon 40 min) te u slučaju početne pH vrijednosti od 5.5 (potpuno uklanjanje nakon 30 min). Tijekom EK procesa dolazi do potrošnje anodnog, ali i katodnog materijala. Potrošnja elektrodnih materijala se povećava s porastom gustoće struje i pH vrijednosti otopine pri čemu je utjecaj gustoće struje izraženiji. Izgled površina elektroda (snimljenih svjetlosnim mikroskopom) ukazuje na činjenicu da se anode tijekom EK procesa otapaju ravnomjerno i lokalno, dok katode uglavnom podliježu ravnomjernoj koroziji.The removal of the dye Crystal Violet (CV) from a aqueous solution (4 ± 0.23 mg/L CV + 2 mg/L NaCl) by the process of electrocoagulation (EC) was performed in two directions. In the first case, the influence of current density (0.016, 0.024, and 0.032 A/cm 2 ; pH = 3.2) was observed, whereas in the second case, the influence of initial pH (3.2, 5.5, and 7.0; i = 0.024 A/cm 2 ) on the removal of CV dye was considered. During the EC process, which lasted 50 minutes, changes in pH, temperature, electrical conductivity, and CV dye concentration were observed. The efficiency of CV dye removal by the EC process is extremely good. At the same time, the dye removal increases with the duration of the process and with the increase of the current density and pH of the solution. Extremely good results were obtained at the highest current density (complete removal after 40 min) and at an initial pH of 5.5 (complete removal after 30 min). During the EC process, anodic and cathodic material is consumed. The consumption of electrode material increases with the increase of current density and pH of the solution, with the influence of current density being more pronounced. The appearance of the electrode surfaces (taken with an light microscope) shows that the anodes dissolve uniformly and locally during the EC process, while the cathodes are mostly subject to uniform corrosion
Stakeholder engagement in the radioactive waste management program : master's thesis
No full textU ovom diplomskom radu dan je kratki pregled gospodarenja radioaktivnim otpadom, s naglaskom na uključivanje dionika u program gospodarenja radioaktivnim otpadom. Dionik je svatko na koga utječe određena aktivnost. Program uključivanja dionika u program gospodarenja radioaktivnim otpadom bitno se razlikuje od države do države. Nemoguće je napraviti jedinstven standardiziran program zbog zakonskih, kulturoloških i demografskih razlika država. U radu je prikazan pregled vijesti i informacija koje Fond za financiranje razgradnje i zbrinjavanja radioaktivnog otpada i istrošenoga nuklearnog goriva Nuklearne elektrane Krško u Hrvatskoj prenosi dionicima. Također je napravljena analiza članaka na najposjećenijim hrvatskim internetskim portalima u kojima se spominje radioaktivni otpad u Hrvatskoj.This master's thesis provides a brief overview of radioactive waste management, with an emphasis on the stakeholder engagement in the radioactive waste management program. A stakeholder is anyone who is affected by a certain activity. Stakeholder engagement in the radioactive waste management program is different in every country. It is not possible to create a unique standardized program due to the legal, cultural and demographic differences between countries. An overview of the news and information that the Fund for financing the decommissioning of the Krško Nuclear Power Plant and the disposal of Krško NPP radioactive waste and spent nuclear fuel conveys to stakeholders was made. Also, an analysis of articles on the most visited Croatian internet portals that mention radioactive waste in Croatia was made
Validation of new target genes of transcription factor GLI3 in human head and neck tumor cell lines
No full textTumori glave i vrata (HNSCC) su je šesti najčešći dijagnosticirani tumor u svijetu. Pacijenti dijagnosticirani s HSNCC imaju lošiju prognozu i limitirane opcije tretmana. Terapije koje ciljaju specifične mete u tim tumorima su još uvijek u razvoju, zato je nužno provesti istraživanja koja su usmjerena na bolje razumijevanje biologije HNSCC, kao i identifikaciju novih biomarkera koji će omogućiti ranije otkrivanje bolesti, ali i predstavljati nove mete za ciljane terapije. Mnoga istraživanja potvrđuju da je signalni put Hedgehog-GLI (HH-GLI) jedan od glavnih čimbenika nužnih za razvoj i održavanje HNSCC. Signalni put HH-GLI je inače uključen u procese embriogeneze, održavanja populacije matičnih stanica i regeneracije tkiva. Abnormalna aktivacija signalnog puta HH-GLI je povezna s nastanokm i razvojem brojnih tumora. Glavni akteri signalnog puta HH-GLI, transkripcijski faktori GLI1, GLI2 i GLI3 potiču prekomjernu ekspresiju proonokogenih gena od kojih je velik broj neidentificiran. Identifikacija i validacija ciljnih gena će omogućiti bolje razumijevanje biologije HNSCC. U tu svrhu sam provela dva nezavisna eksperimenta na dvije stanične linije HNSCC. Stanice su u jednom eksperimentu bile tretirane s inhibitorima signalnog puta HH-GLI, a u drugom s plazmidnim vektorima koji kodiraju GLI3 konstrukte. Analizom rezultata kvantitativnog real-time PCR-a potvrđeno je 6 gena koji su regulirani transkripcijskim faktorom GLI3, što ih čini atraktivnim metama za nove terapijske pristupe.Tumors of the head and neck (HNSCC) are the sixth most diagnosed tumors in the world. Patients diagnosed with HNSCC have a poor prognosis and limited treatment options. Therapies targeting specific targets within the tumor are still in development, which is why it is necessary to conduct research focused on a better understanding of the biology of HNSCC, as well as the identification of new biomarkers for early disease prediction and as new targets for targeted therapies. Many studies confirm that the Hedgehog-GLI (HH-GLI) signaling pathway is one of the main factors necessary for the development and maintenance of HNSCC. The HH-GLI signaling pathway is otherwise involved in embryogenesis, maintenance of stem cell, and tissue regeneration. Abnormal activation of the HH-GLI signaling pathway is associated with the tumorigenesis of numerous tumors. This is enabled via transcription factors GLI1, GLI2, and GLI3 who promote the overexpression of pro-oncogenic genes, many of which remain unidentified. The identification and validation of these genes will enable a better understanding of the biology of HNSCC. For this purpose, I conducted two independent experiments on two HNSCC cell lines. In one experiment, cells were treated with HH-GLI signaling pathway inhibitors, and in the other, they were transfected with plasmid vectors encoding GLI3 constructs. Analysis of the quantitative real-time PCR results confirmed the regulation of 6 genes by the transcription factor GLI3, making them prime targets for new therapeutic approaches