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Effect of grinding techniques on the microstructure and powder characterization of purslane (Portulaca oleracea L.) and phenolic content in water extract before and after in vitro simulated digestion : bachelor thesis
No full textTušt (Portulaca oleracea L.) je biljka prepoznata kao vrijedan izvor hranjivih tvari i bioaktivnih spojeva, poput omega-3 masnih kiselina, antioksidansa, vitamina i minerala. Unatoč tradicionalnoj percepciji kao korova, tušt ima visoku nutritivnu vrijednost i široku primjenu u prehrani. Ovaj rad istražuje proizvodnju praha od liofiliziranog tušta koji zadržava hranjive tvari te se koristi kao dodatak prehrani. Fokus je na ispitivanju razlika u mikrostrukturi prahova dobivenih različitim tehnikama mljevenja (mlin s noževima, kuglični mlin, planetarni mlin), analizi raspodjele veličina čestica, nasipne gustoće i parametara boje te udjela i sastava fenola prije i poslije simuliranog procesa probave. Rezultati su pokazali da različite tehnike mljevenja značajno utječu na mikrostrukturu, veličinu čestica i stabilnost bioaktivnih spojeva, s kugličnim mljevenjem kao najpovoljnijim za očuvanje fenola. Granulometrijska analiza otkrila je najveću zastupljenost čestica veličine 200 µm nakon mljevenja mlinom s noževima i kugličnim mlinom, dok su kod planetarnog mlina prevladavale čestice iznad 200 µm. Nasipna gustoća praha bila je najviša kod mljevenja kugličnom mlinom što je ujedno doprinijelo svojstvima tečenja. Analiza boje pokazala je da je prah nakon mljevenja planetarnim mlinom imao najtamniju boju zbog oksidacije materijala, dok je mljevenje kugličnim mlinom najmanje utjecalo na promjenu boje. Nakon simulirane probave, fenolni spojevi su pokazali visoku stabilnost, osobito nakon želučane faze probave, dok je stabilnost opadala nakon crijevne faze. Mljevenje kugličnim mlinom dalo je najbolje rezultate u očuvanju fenola nakon obje faze probave, dok su nesamljeveni uzorci imali najveću biodostupnost fenolnih spojeva. Ovi rezultati ukazuju na značajan potencijal tušta kao funkcionalne hrane i dodatka prehrani, posebice u obliku praha, te na važnost optimizacije tehnika mljevenja i skladištenja kako bi se očuvale hranjive i bioaktivne komponente.Purslane (Portulaca oleracea L.) is a plant recognized as a valuable source of nutrients and bioactive compounds, such as omega-3 fatty acids, antioxidants, vitamins, and minerals. Although traditionally perceived as a weed, purslane has high nutritional value and is widely used in food. This paper investigates the production of powder from lyophilized purslane, which retains its nutrients and is used as a dietary supplement. The focus is on examining the differences in the microstructure of powders obtained using different milling techniques (blade mill, ball mill, planetary mill), analyzing particle size, bulk density, color parameters, and the content and composition of phenols before and after a simulated digestion process. The results showed that different milling techniques significantly affect the microstructure, particle size, and stability of bioactive compounds, with ball milling being the most favorable for phenol preservation. Granulometric analysis revealed the largest representation of 200 µm particles after milling with blade and ball mills, while particles larger than 200 µm dominated after milling with the planetary mill. The bulk density of the powder was highest with ball milling, which also contributed to flow properties. Color analysis showed that powder after planetary milling had the darkest color due to material oxidation, while ball milling had the least impact on color retention. After simulated digestion, phenolic compounds showed high stability, particularly after the gastric digestion phase, while stability decreased after the intestinal phase. Ball milling gave the best results for phenol preservation after both phases of digestion, while unmilled samples had the highest bioavailability of phenolic compounds. These results highlight the significant potential of purslane as a functional food and dietary supplement, especially in powder form, and the importance of optimizing milling and storage techniques to preserve its nutritional and bioactive components
Urban tourism in the city of Split
No full textOvaj rad istražuje obilježja urbanog turizma na području grada Splita. Cilj istraživanja bio je analiza motivacije, obilježja, aktivnosti i zadovoljstva turista posjetom Splitu, te izdvajanje tipova turista koji posjećuju Split s obzirom na ponašanje i preferencije. Podaci su prikupljeni metodom ankete među turistima koji su posjetili Split kroz čitavu godinu. Rezultati pokazuju kako su kulturna baština i znamenitosti najvažniji motivacijski čimbenik među ispitanicima. Ispitanici u velikom broju sudjeluju u aktivnostima vezanima za kulturnu baštinu, te su vrlo zadovoljni ponudom. Ističe se i motivacija sudjelovanjem u ljetnom kupališnom turizmu, što je i razlog izražene sezonalnosti. Ipak, suprotno tradicionalnim destinacijama kupališnog turizma, nešto kompleksnija ponuda grada Splita uzrok je tome da ispitanici tijekom boravka sudjeluju u različitim aktivnostima. Izazovi sezonskog pritiska ogledaju se u turističkom iskustvu, što potvrđuju najniže ocjene zadovoljstva boravkom tijekom ljeta. Stoga je nužno pažljivo usmjeravati razvoj turizma u Splitu kako bi se ublažio sezonski pritisak, očuvao identitet mediteranskog grada te osigurala dugoročna održivost destinacije.This paper explores urban tourism in the city of Split. The research aimed to analyze the motivation, characteristics, activities, and satisfaction of tourists visiting Split, and identify the types of tourists based on their behavior and preferences. A survey was conducted among tourists who visited Split throughout the year. The results indicate that cultural heritage and landmarks are the most important motivational factors - many respondents participated in related activities and express high satisfaction. Additionally, there is a strong motivation to participate in beach summer tourism, which contributes to the pronounced seasonality of tourist arrivals. Unlike traditional beach tourism destinations, the complex offer of the city of Split encourages the respondents to participate in various activities. The challenges of seasonal pressure are reflected in the tourist experience, as evidenced by the lowest satisfaction ratings during the summer. Therefore, it is crucial to direct the development of tourism in Split to mitigate seasonal pressure and ensure the long-term sustainability of the destination
Mechanochemical activation by grinding with cyclodextrins as a strategy to enhance the solubility of cinnarizine
No full textCinarizin je lijek, po strukturi derivat piperazina, koji ima antihistaminsko, antiserotonergično,
antidopaminergično djelovanje, a ujedno je i blokator kalcijevih kanala koji pokazuje ograničenu, pH ovisnu
topljivost in vitro i visoka permeabilnost in vivo. Stvaranje inkluzijskih kompleksa s ciklodekstrinima jedan
je od načina kojima se može utjecati na topljivost uklopljenog lijeka. U ovom diplomskom radu istražen je
utjecaj inkluzijskih kompleksa cinarizina s β-ciklodekstrinom, hidroksipropil-β-ciklodekstrinom i
sulfobutileter-β-ciklodekstrinom, pripremljenih metodom mljevenja, na brzinu i opseg in vitro otapanja
cinarizina u simuliranom duodenalnom mediju pri pH 4,5. Za potrebe kvantitativnog određivanja cinarizina
u uzorcima razvijena je i validirana UV/Vis spektroskopska metoda. Mljevenje je provedeno na
visokoenergijskom vibracijskom mlinu pri frekvencijama 20 i 30 Hz u različitim vremenima. Nastajanje
ciklodekstrinskih kompleksa cinarizina praćeno je primjenom termoanalitičkih metoda, a in vitro oslobađanje
CIN provedeno je na uređaju s lopaticom. Kao ključni tehnološki parametar s utjecajem na opseg interakcije
lijeka i ciklodekstrina pokazala se frekvencija mljevenja, a kompleks sa hidroksipropil-β-ciklodekstrinom
pripremljen mljevenjem tijekom 20 minuta na 30 Hz pokazuje najveći potencijal za daljnju primjenu. Pri
tome, funkcionalnost ovog kompleksa potrebno je dalje ispitati primjenom složenijih, biorelevantnih metoda
kojima se precizno oponašaju uvjeti prisutni u probavnom sustavu.Cinnarizine is a drug, a derivative of piperazine, which exhibits antihistaminic, antiserotonergic, and
antidopaminergic effects. It is also a calcium channel blocker that demonstrates limited, pH-dependent
solubility in vitro and high permeability in vivo. The formation of cyclodextrin inclusion complexes is an
effective approach to enhance the solubility of the incorporated drug. In this thesis, the influence of the
inclusion complexation of cinnarizine with β-cyclodextrin, hydroxypropyl-β-cyclodextrin, and sulfobutyl
ether-β-cyclodextrin, prepared using the grinding method, on the rate and extent of in vitro dissolution of
cinnarizine in a simulated duodenal medium at pH 4.5 was investigated. A UV/Vis spectroscopic method was
developed and validated to quantitatively determine cinnarizine in samples prepared by grinding. Grinding
was conducted on a high-energy vibration mill at 20 and 30 Hz frequencies, applying various processing
times. The formation of cyclodextrin complexes with cinnarizine was monitored using thermoanalytical
methods, and in vitro release of CIN was conducted using a paddle apparatus. The milling frequency was
identified as a crucial technological parameter affecting the degree of drug-cyclodextrin interaction, and the
complex with hydroxypropyl-β-cyclodextrin prepared by milling for 20 minutes at 30 Hz demonstrated the
highest enhancement of in vitro dissolution properties. However, the functionality of this complex requires
further testing using more intricate, biorelevant methods that accurately replicate the conditions present in
the digestive system
Health literacy of hospitalized patients suffering from diseases of the gastrointestinal tract
No full textCilj: utvrditi razinu zdravstvene pismenosti i prediktore zdravstvene pismenosti kod gastroenteroloških bolesnika.
Izvori podataka i metode: Istraživanje je provedeno u Kliničkom bolničkom centru Split, na Zavodu za gastroenterologiju i hepatologiju. Sudjelovalo je 250 ispitanika, koji su popunili papirnati upitnik koji se sastojao od dvije dijela: općih podataka o bolesniku i modificiranog Europskog upitnika za procjenu zdravstvene pismenosti (HLS-EU-16). Za obradu podataka korišteni su deskriptivna statistika i Hi kvadrat test.
Rezultati: Rezultati istraživanja su pokazali da više od 80 % ispitanika ima adekvatnu i izvrsnu zdravstvenu pismenost (47,2 % adekvatnu, a 36,5 % izvrsnu zdravstvenu pismenost). Dob (30-59 godina), duljina trajanja bolesti, liječenje u Dnevnoj bolnici, mišljenje o posjedovanju znanja o svoj bolesti i odlasci na preventivne zdravstvene preglede su prediktori koji su statistički značajno povezani s razinom zdravstvene pismenosti bolesnika oboljelih od bolesti gastrointestinalnog trakta. Rezultati su također pokazali da spol, razina obrazovanja, izvori prikupljanja informacija o svojoj bolesti i provjeravanje informacija s interneta kod zdravstvenih djelatnika nisu statistički značajno povezani s razinom zdravstvene pismenosti.
Zaključak: Razina zdravstvene pismenosti hospitaliziranih gastroenteroloških bolesnika u cjelini je zadovoljavajuća, što potvrđuje prvu istraživačku hipotezu. Provedeno istraživanje naglašava važnost
poboljšanja zdravstvene pismenosti kao ključnog čimbenika za poboljšanje zdravstvenih ishoda i smanjenje troškova zdravstvene skrbi.Objective: to determine the level of health literacy and predictors of health literacy in gastroenterological patients.
Data sources and methods: The study was conducted at the University Hospital Center Split, at the Department of Gastroenterology and Hepatology. 250 respondents participated, who filled out a paper questionnaire consisting of two parts: general patient data and the modified European Health Literacy Assessment Questionnaire (HLS-EU-16). Descriptive statistics and the Chi-square test were used to process the data.
Results: The results of the study showed that more than 80 % of the respondents had adequate and excellent health literacy (47.2 % adequate and 36.5 % excellent health literacy). Age (30-59 years), duration of illness, treatment in a Day Hospital, opinion about having knowledge about one's illness and visits to preventive health examinations are predictors that are statistically significantly associated with the level of health literacy of patients with gastrointestinal diseases. The results also showed that gender, level of education, sources of information about their illness, and checking information from the Internet among healthcare professionals were not statistically significantly associated with the level of health literacy.
Conclusion: The level of health literacy of hospitalized gastroenterology patients is generally satisfactory, which confirms the first research hypothesis. The conducted research emphasizes the importance of improving health literacy as a key factor for improving health outcomes and reducing healthcare costs
Ibuprofen removal from aqueos solution by sorption on different low-cost sorbents : diploma thesis
No full textPovećana i nekontrolirana uporaba farmaceutika diljem svijeta postaje sve značajniji ekološki problem. Ibuprofen je među najprodavanijim lijekovima bez recepta u svijetu, što dovodi do porasta njegove koncentracije u postrojenjima za obradu otpadnih voda, a uslijed nedovoljne učinkovitosti konvencionalnih metoda obrade, pojavljuje se i u vodnim tijelima koja se crpe za vodoopskrbu. Zbog brojnih fizioloških, hormonalnih i reproduktivnih poremećaja koje uzrokuje kod vodenih organizama, jasna je potreba za razvijanjem metoda učinkovitijeg uklanjanja ibuprofena iz voda. U ovome radu ispitano je uklanjanje ibuprofena iz vodene otopine koncentracije ≈ 1 mg/L sorpcijom na prirodnom zeolitu klinoptilolitu, njegovim modificiranim oblicima (natrijevom, željezovom i sumporovom) te na nusproizvodima prerade voća - košticama maslina, trešanja i višanja. Samo su koštice višanja pri ispitanim eksperimentalnim uvjetima pokazale učinkovitost od 30,15 % u uklanjanju ibuprofena iz vodene otopine s postignutim kapacitetom od 0,025 mg/g. Neučinkovitost ostalih sorbenasa je najvjerojatnije rezultat elektrostatskog odbijanja njihove izrazito negativne površine i deprotonirane molekule ibuprofena pri pH vrijednostima tijekom sorpcije. Buduća istraživanja trebalo bi usmjeriti ka modifikaciji materijala s ciljem poboljšanja njihovih sorpcijskih svojstava, ali i prilagođavanju eksperimentalnih uvjeta svojstvima onečišćujuće tvari, u svrhu postizanja što potpunijeg uklanjanja. Također, treba raditi na uvrštavanju farmaceutika na listu prioritetnih tvari u analizi vode budući da još uvijek ne postoji zakonska regulativa s maksimalno dopuštenim koncentracijama farmaceutika u prirodnim vodama koje se crpe za vodoopskrbu. U konačnici, nužno je poraditi na odgovornom zbrinjavanju lijekova kako bi se spriječili dugoročni učinci na bioraznolikost vodenih organizama, ali i ljude koji ovise o tim ekosustavima.The increased and uncontrolled use of pharmaceuticals worldwide is becoming a significant environmental problem. Ibuprofen is among the most sold over-the-counter drugs in the world, which leads to an increase in its concentration in wastewater treatment plants. Due to the insufficient efficiency of conventional water treatment methods, it also appears in water bodies that are pumped for water supply. Due to the numerous physiological, hormonal and reproductive disorders it causes in aquatic organisms, there is a clear need to develop methods for more effective removal of ibuprofen from water. In this paper, the removal of ibuprofen from an aqueous solution with a concentration of ≈ 1 mg/L by sorption on natural zeolite clinoptilolite, its modified forms (sodium, iron and sulfur) and on fruit processing by-products - olive, cherry and sour cherry pits was examined. Only sour cherry pits showed effectiveness (30.15%) in ibuprofen removal from aqueous solution under the tested experimental conditions, with a capacity of 0.025 mg/g. The ineffectiveness of other sorbents is most likely the result of electrostatic repulsion of their extremely negative surface and deprotonated ibuprofen molecule at pH values during sorption. Future research should be focused towards materials modification with the aim of improving their sorption properties, but also to the adaptation of experimental conditions to the properties of the pollutant, in order to achieve more effective treatment. Efforts should be made to include pharmaceutical residues on the list of priority substances in water analysis, as there is still no legal regulation specifying the maximum allowable concentrations of pharmaceuticals in natural waters used for water supply. Ultimately, responsible disposal of pharmaceutical products is necessary to prevent long-term effects on the biodiversity of aquatic organisms, as well as the people who depend on these ecosystems
Sorption of copper on NaX and Saccharomyces cerevisiae yeast incorporated in alginate : diploma thesis
No full textU ovom radu ispitivala se ravnoteža sorpcije bakrovih iona na zeolitu NaX čestica srednjeg promjera manjeg od 40 µm te suhom pekarskom kvascu Saccharomyces cerevisiae čestica srednjeg promjera manjeg od 160 µm ugrađenima u alginat. Eksperiment se proveo korištenjem suspenzija zeolita NaX, odnosno suhog pekarskog kvasca Saccharomyces cerevisiae imobiliziranih u alginatu i otopine bakrovog(II) klorida dihidrata različitih početnih koncentracija. Pripremljene suspenzije smještene su u vodenu kupelj s trešnjom pri izotermnim uvjetima (T = 27 °C) i brzini od 200 okr./min. Suspenzije su uzorkovane, filtrirane, a filtrati analizirani UV/Vis spektrofotometrom u određenim vremenskim intervalima tijekom 72 sata kako bi se pratilo uspostavljanje ravnoteže u ispitivanom sustavu. Dobiveni eksperimentalni podatci analizirani su Freundlichovom, Langmuirovom, Redlich-Petersonovom i Sipsovom izotermom. Grafičko slaganje dobivenih eksperimentalnih podataka s adsorpcijskim izotermama te vrijednosti izračunatog RMSE i hi-kvadrat testa pokazali su da Langmuirova izoterma najbolje opisuje proces sorpcije bakrovih iona na zeolitu NaX ugrađenom u alginat i proces sorpcije bakrovih iona na pekarskom kvascu Saccharomyces cerevisiae ugrađenima u alginat. Učinkovitost sorpcije smanjuje se porastom početne koncentracije otopine bakrovog(II) klorida dihidrata, a ravnotežno stanje u svim suspenzijama postignuto je nakon 24 sata. Količina bakrovih iona vezanih u ravnoteži ovisna je o početnim koncentracijama otopina; uočava se kako porast početne koncentracije otopine bakrovih iona uglavnom dovodi do rasta količine bakrovih iona vezanih na zeolitu NaX i pekarskom kvascu Saccharomyces cerevisiae ugrađenima u alginat.In this thesis, the equilibrium of copper ion sorption on zeolite NaX, with a mean particles diameter of less than 40 µm, and on dry baker’s yeast Saccharomyces cerevisiae with a mean particles diameter of less than 160 µm incorporated in alginate was investigated. The experiments were carried out using suspension of zeolite NaX, respectively dry baker's yeast Saccharomyces cerevisiae incorporated in alginate and copper(II) chloride dihydrate solution with different initial concentrations. The prepared suspensions were placed in a water bath shaker under isothermal conditions (T = 27 °C) and at a speed of 200 rpm. The suspensions were sampled, filtered, and filtrates were analysed at specific time intervals over a period of 72 hours using a UV/Vis spectrophotometer to verify the establishment of equilibrium in the system under investigation. The experimental data obtained were analysed using the Freundlich, Langmuir, Redlich-Peterson and Sips isotherms. The graphical fit of the experimental data with the adsorption isotherms and the calculated RMSE and chi-square test parameters showed that the Langmuir isotherm best describes the sorption process of copper ions on NaX zeolite and the sorption process of copper ions on Saccharomyces cerevisiae baker's yeast incorporated in alginate. The sorption efficiency decreases with the increase of the initial concentration of the copper(II) chloride dihydrate solution, the equilibrium state was reached in all suspensions after 24 hours. The amount of copper ions retained at equilibrium depends on the initial concentrations of the solutions. It can be observed that an increase in the initial concentration of the copper ion solution mainly leads to an increase in the amount of copper ions sorbed on zeolite NaX and to the baker's yeast Saccharomyces cerevisiae incorporated in alginate
Thermal analysis of polyethylene oxide composite with addition of the magnesium oxide : diploma thesis
No full textU ovom radu istražen je utjecaj dodatka magnezijeva oksida (MgO) na toplinska svojstva i stabilnost kompozita na bazi poli(etilen-oksida) (PEO). Korištenjem diferencijalne pretražne kalorimetrije (DSC) i termogravimetrijske analize (TGA) ispitane su toplinske karakteristike PEO/MgO kompozita. Dodatak MgO snižava karakteristiĉne toplinske prijelaze PEO kompozita, ukljuĉujući temperaturu staklastog prijelaza (T g ), zbog smanjenja kristalnosti. TakoĊer, pogoršava toplinsku stabilnost PEO u kompozitu jer snižava temperaturu poĉetka razgradnje kompozita.This paper investigates the effect of magnesium oxide (MgO) addition on the thermal properties and stability of poly(ethylene oxide) (PEO)-based composites. The thermal characteristics of PEO/MgO composites were examined using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The addition of MgO reduces the characteristic thermal transitions of the PEO composite, including the glass transition temperature (T g ), due to the reduction in crystallinity. Furthermore, it worsens the thermal stability of the PEO composite by lowering the decomposition onset temperature
Strength and stiffness assessment of main bridge crane girder with asymmetrical design by finite element method
No full textU ovom radu proveden je numerički proračun čvrstoće i krutosti glavnog nosača mosne dizalice konstruirane za rukovanje zaštitnim poklopcima na komorama za ispitivanje materijala za izgradnju fuzijskih elektrana. U uvodnom dijelu rada objašnjena je motivacija rada te su opisane osnovne značajke samog procesa nuklearne fuzije, ogroman potencijal koji fuzija posjeduje te samim time i opravdanost ulaganja ogromnih resursa u tom području, ali i veliki izazovi s kojima se znanstvenici još uvijek suočavaju. U drugom poglavlju dan je teorijski pregled metode konačnih elemenata te su opisane osnovne karakteristike korištenih konačnih elemenata te važne značajke kod modeliranja kontakta. Zatim je na temelju postojećeg CAD modela s određenim preinakama u geometriji kako bi se pojednostavila analiza kreiran numerički model s grednim, odnosno heksaedarskim elementima. Potom je provedena analiza metodom konačnih elemenata u programskom paketu Abaqus. Za dva kritična slučaja opterećenja, odnosno dva različita položaja tereta na glavnom nosaču mosne dizalice, određeno je stanje naprezanja i pomaka glavnog te čeonog nosača koji služi kao oslonac glavnom nosaču. Rezultati dobiveni numeričkom analizom zatim su interpretirani i uspoređeni s rezultatima dobivenim analitičkim proračunom prema normi EN 13001 na temelju čega je donesen zaključak.This thesis considers the strength and stiffness assessment of main bridge crane girder intended for the handling of protective covers on the chambers for testing materials for the construction of a fusion power plant. In the introductory part of the paper, the motivation of the work is explained and the basic features of the nuclear fusion process, the enormous potential that fusion possesses and thus the justification of investing huge resources in that area are described, as well as the great challenges that scientists still face. In the second chapter, a theoretical overview of the finite element method is given and the basic characteristics of the used finite elements and important features in contact modeling are described. Then, based on the existing CAD model with certain modifications in the geometry in order to simplify the analysis, a numerical model with beam and hexahedral elements was created. The analysis was then carried out using the finite element method in the Abaqus software package. For two critical load cases, that is, two different positions of the load on the main girder of the bridge crane, the state of stress and displacement of the main girder and the end girder, which serves as a support for the main girder, was determined. The results obtained by numerical analysis were then interpreted and compared with the results obtained by analytical calculation according to EN 13001
Project of low-floor electric minibus
No full textPolazište za realizaciju ovog projekta su do sada obavljeni razvojni zadaci od strane Katedre za motore i vozila, Fakulteta strojarstva i brodogradnje, Sveučilišta u Zagrebu. U okviru diplomskog rada je napravljen pretprojekt novog multifunkcionalnog niskopodnog minibusa kojim se sagledao koncept vozila, aktivnosti potrebne za pokretanje proizvodnje i plasmana vozila na tržište. Analizirana je situacija na tržištu s ciljem određivanja konkurencije novog vozila, veličine i vrijednosti tržišta, te tržišni potencijal proizvoda. Razmatrani su mogući modeli komercijalizacije projekta minibusa.
Nadalje, tijekom pisanja ovog rada napravljen je pregled i usporedba linija javnog gradskog prijevoza te drugih konkurentnih prijevoznih sredstva. Zaključno, izračunata je potrošnja energije po jedinici puta za sve oblike javnog prijevoza, a sve kako bi se utvrdila isplativost supstitucije postojećih oblika javnog prijevoza s multifunkcionalnim niskopodnim vozilom, MUNIV-om.A starting point for the realisation of this project derives from the development tasks presented by the Department for engines and vehicles, Faculty of mechanical engineering and naval architecture, University of Zagreb.
Within the scope of the master thesis, a pre-project of a new multifunctional low-floor minibus was formed, which outlined the concept of the vehicle and the activities required to initiate the production, product placement and marketing of the vehicle.
A market analysis was performed to determine product competition, size and value of the market and the market potential of the product. Possible models for commercialisation of the minibus project were considered.
In addition to the abovementioned analysis, an overview and comparison of available public transport lines and other competitive means of transport were made.
In conclusion, the energy consumption per unit of transportation was calculated for all modes of public transport with the main objective to determine the cost-effectiveness of replacing existing forms of public transport with a multifunctional low-floor vehicle, MUNIV
Development of capillary electrophoretic method for analysis of talazoparib
No full textTalazoparib je noviji lijek koji se u posljednjim godinama sve više primjenjuje kod bolesnika s određenim tipovima karcinoma dojke i karcinoma prostate, a ispituje se i za druge indikacije. Cilj ovog istraživanja bio je razviti brzu, jednostavnu i pouzdanu kapilarnoelektroforetsku metodu za analizu talazopariba. Budući da je talazoparib negativno nabijen u lužnatom mediju, koji je preliminarnim ispitivanjima određen kao optimalan za ovu analizu, odabrana je kapilarna zonska elektroforeza.
U ovom radu ispitani su različiti parametri za analizu talazopariba kapilarnom elektroforezom. Analize su provedene na uređaju sa integriranim detektorom niza dioda na kapilari od izvučenog kvarca duljine 37,5 cm, duljine puta do detektora od 29,5 cm i unutrašnjeg promjera 50 μm. Detekcija se provodila na valnoj duljini 310 nm. Uzorci su hidrodinamički injektirani u kapilaru pod tlakom od 50 mbar tijekom 6 sekundi.
Tijekom eksperimenta ispitana su dva radna pufera: fosfatni pufer (pH 2,5) i boratni pufer (pH u rasponu 9,3-10,75). Optimalnim se pokazao 40 mM boratni pufer pH 10,75 zbog najkraće analize te najboljeg razlučivanja i simetrije pika. Kako bi se dodatno poboljšalo razlučivanje u pufer je dodan metanol (0-10 %). Za daljnju analizu odabran je pufer koji sadrži 10 % metanola zbog najboljeg razlučivanja. Pri naponu 22,5 kV vrijeme migracije talazopariba je bilo najkraće, a pikovi su bili uski i simetrični. Pri tempertauri 35°C vrijeme migracije je bilo najkraće, a površina pika najveća uz minimalan utjecaj na druge parametre pa je zaključeno da su ti uvjeti optimalni za analizu talazopariba kapilarnom zonskom elektroforezom.Talazoparib is a newer drug that has been used more in patients with certain types of breast and prostate cancer in recent years and it is also being tested for other indications. The goal of this study was to develop a fast, simple and reliable capillary electrophoretic method for the analysis of talazoparib. Since talazoparib is negatively charged in the alkaline medium that preliminary studies have determined to be optimal for this analysis, capillary zone electrophoresis was chosen.
In this study, various parameters for the analysis of talazoparib by capillary electrophoresis were tested. The analyses were performed on a device with an integrated diode array detector on a 37,5 cm long, 29,5 cm path length to the detector, and 50 μm internal diameter. Detection was performed at a wavelength of 310 nm. Samples were hydrodynamically injected into the capillary under a pressure of 50 mbar for 6 seconds.
During the experiment, two buffers were tested: phosphate buffer (pH 2,5) and borate buffer (pH range 9,3-10,75). The optimal one was 40 mM borate buffer pH 10,75 due to the shortest analysis and the best resolution and peak symmetry. In order to further improve the resolution methanol (0-10 %) was added to the buffer. For further analysis, a buffer containing 10 % methanol was chosen due to the best resolution. At a voltage of 22,5 kV, the migration time of talazoparib was the shortest, the peaks were narrow and symmetrical. At a temperature of 35°C, the migration time was shortest and the peak area was largest with minimal impact on other parameters, so it was concluded that these conditions were optimal for the analysis of talazoparib by capillary zone electrophoresis