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Optimization and validation of HPLC method for the simultaneous determination of prednisolone derivatives
No full textGlukokortikoidi su skupina lijekova koji se sve češće primjenjuju u suvremenoj medicinskoj praksi zbog svojih izraženih
protuupalnih i imunosupresivnih svojstava. Koriste se u liječenju širokog spektra upalnih bolesti, uključujući astmu,
upalne bolesti crijeva, alergije te različite bolesti oka. Ipak, njihova dugotrajna primjena povezana je s ozbiljnim
nuspojavama kao što su Cushingov sindrom, neurološke smetnje, glaukom i srčano zatajenje, što ističe potrebu za
razvojem pouzdanih analitičkih metoda za njihovo ispitivanje.
U ovom radu analizirani su su prednizolon fosfat i prednizolon acetat, a cilj je bio razviti i validirati HPLC metodu
sukladno ICH Q2(R2) smjernicama, te kvantificirati njihov sadržaj u prahu djelatne tvari i model uzorku. Primjenom
HPLC-DAD metode sa gradijentnom elucijom postignuto je učinkovito razdvajanje analita pri temperaturi od 50 °C i
valnoj duljini od 254 nm. Metoda je zadovoljila sve zahtjeve validacijskih parametara. Dobiveni rezultati pokazali su da
je sadržaj oba analita u ispitivanim uzorcima unutar propisanih granica prema važećim farmakopejskim standardima.Glucocorticoids are a group of drugs increasingly used in modern medical practice due to their pronounced antiinflammatory and immunosuppressive properties. They are used in the treatment of a wide range of inflammatory
diseases, including asthma, inflammatory bowel diseases, allergies, and various ocular conditions. However, their longterm use is associated with serious side effects such as Cushing's syndrome, neurological disorders, glaucoma, and heart
failure, highlighting the need for the development of reliable analytical methods for their examination.
In this study, prednisolone phosphate and prednisolone acetate were analyzed, with the aim of developing and validating
an HPLC method in accordance with ICH Q2(R2) guidelines and quantifying their content in the active pharmaceutical
ingredient powder and a model sample. By applying the HPLC-DAD method with gradient elution, effective separation
of the analytes was achieved at a temperature of 50°C and a wavelength of 254 nm. The method met all validation
parameter requirements. The obtained results showed that the content of both analytes in the tested samples was within
the prescribed limits according to current pharmacopoeial standards
Hair as a Biological Trace at the Scene of a Vehicle-Animal Collision
No full textU aspektu sudskog veterinarstva i veterinarske forenzike, ključnu značajku sadrži
upravo dlaka kao najčešći oblik dokaza na mjestu naleta motornog vozila na životinju.
Zahvaljujući iznimnoj otpornosti na vanjske uvjete, dlaka preživljava i u manje
pogodnim okolnostima, omogućavajući tako analizu u svrhu identifikacije pojedine
životinjske jedinke. Strukturno gledano, dlaka se sastoji od medule (srži vlasi), korteksa
(središnjega, nosivog sloja) i kutikule (vanjskog, zaštitnog sloja). Morfološka obilježja
svake od ovih komponenti mogu, ovisno o vrsti, značajno varirati, pa nam mikroskopski
pregled daje vrijedne informacije o redu ili čak porodici kojoj životinja pripada.
Međutim, kada je riječ o blisko srodnim vrstama ili potencijalno hibridnim sojevima,
isključivo morfološka analiza može biti nedostatna. U takvim slučajevima posežemo
za molekularnim metodama (npr. PCR, PCR-RFLP ili sekvenciranjem), koje, unatoč
većim troškovima i tehničkoj složenosti, nude detaljnu genetičku potvrdu identiteta. U
ovoj su studiji opisane i makroskopske i mikroskopske karakteristike dlake, uz poseban
naglasak na sedam europskih sisavaca: divlju svinju (Sus scrofa), jelena običnog
(Cervus elaphus), jelena lopatara (Dama dama), srnu (Capreolus capreolus), lisicu
(Vulpes vulpes), psa (Canis lupus), mačku (Felis silvestris forma catus) te običnog
europskog zeca (Lepus europaeus). Dodatno su predstavljeni sudski slučajevi iz prakse,
gdje ove spoznaje o strukturi i molekularnoj analizi dlake nalaze svoju konkretnu
primjenu. Na taj se način jasno pokazuje kako teorijske informacije iz područja
morfologije dlake i molekularne forenzike mogu biti presudne u rasvjetljavanju nesreća
s divljim i domaćim životinjama, ali i u rješavanju sudskih procesa ili nezakonitih radnji
koje uključuju životinje.Within the context of forensic veterinary medicine and veterinary forensics, hair
emerges as the key form of evidence at the site of a vehicle–animal collision. Due to its
remarkable resilience to environmental factors, hair often survives under less favorable
conditions, thus allowing for an analysis aimed at identifying the individual animal.
Structurally, hair is composed of the medulla (the core), the cortex (the central,
supportive layer), and the cuticle (the outer, protective layer). The morphological
features of each of these components can vary considerably depending on the species,
which is why microscopic examination can yield valuable information about the order
or even the family to which the animal belongs. However, when it comes to closely
related species or potentially hybrid strains, relying solely on morphological analysis
may be insufficient. In such cases, we resort to molecular methods (e.g., PCR, PCRRFLP, or sequencing), which, despite higher costs and technical complexity, offer a
detailed genetic confirmation of identity. This study describes both the macroscopic
and microscopic characteristics of hair, with particular emphasis on seven European
mammals: the wild boar (Sus scrofa), red deer (Cervus elaphus), fallow deer (Dama
dama), roe deer (Capreolus capreolus), fox (Vulpes vulpes), dog (Canis lupus), cat
(Felis silvestris forma catus), and the European hare (Lepus europaeus). In addition,
real-life court cases are presented, illustrating how these insights into hair structure and
molecular analysis are applied in practice. In this way, it becomes evident that
theoretical knowledge from the field of hair morphology and molecular forensics can
be crucial for clarifying accidents involving both wild and domestic animals, as well as
for resolving legal proceedings or unlawful activities related to animals
Aerodynamic model of a modern fighter aircraft for subsonic speeds
No full textU ovom diplomskom radu razvijen je prošireni aerodinamički model dvomotornog borbenog zrakoplova IR-1, temeljen na konfiguraciji sličnog realnom zrakoplovu Dassault Rafale. Cilj rada bio je izraditi vjerodostojan aerodinamički model za podzvučne režime leta, s naglaskom na definiranje i modeliranje aerodinamičkih gradijenata koji utječu na uzdužno i bočno gibanje letjelice.
Na temelju preuzetih geometrijskih značajki definirani svi ključni aerodinamički parametri i koeficijenti sila i momenata. Model uključuje ovisnosti aerodinamičkih koeficijenata o napadnom kutu, kutu klizanja, kutnim brzinama, otklonima upravljačkih površina te Machovom broju, što predstavlja unaprijeđenje postojećeg modela koji je bio ograničene primjene s obzirom na Machov broj. Metodama projektne aerodinamike izračunate su konkretne vrijednosti gradijenata u pet referentnih točaka Machova broja koje su aproksimirane polinomom za cijelo područje podzvučnih brzina. Obrađeni su stacionarni i nestacionarni gradijenti, kao i metode procjene maksimalnog koeficijenta sile uzgona i brzine sloma uzgona te hvatišta normalne sile.
Razvijeni model omogućuje kvalitetnu simulaciju leta zrakoplova u podzvučnom režimu i pruža temelj za precizno predviđanje ponašanja letjelice u različitim režimima leta. Rezultati ovog rada mogu se koristiti za integraciju u simulacijske sustave te kao podloga za daljnji razvoj simulatora leta.This thesis presents the development of an enhanced aerodynamic model for the twin-engine fighter aircraft IR-1, based on the configuration of the real-world Dassault Rafale. The objective was to create a reliable aerodynamic model for subsonic flight regimes, with a focus on defining and modelling the aerodynamic gradients that influence both longitudinal and lateral aircraft motion.
Using the provided geometric characteristics, all key aerodynamic parameters and force and moment coefficients were defined. The model incorporates dependencies of aerodynamic coefficients on angle of attack, sideslip angle, angular rates, control surface deflections, and Mach number, representing an improvement over the previous model, which was limited in terms of Mach number applicability.
Gradient values were calculated using preliminary aerodynamic methods at five reference Mach numbers and approximated with polynomial functions to cover the entire subsonic speed range. Both steady and unsteady aerodynamic gradients were considered, along with methods for estimating maximum lift coefficient, stall speed, and normal force center location.
The developed model enables accurate flight simulation of the aircraft in subsonic conditions and provides a foundation for predicting aircraft behavior across various flight regimes. The results can be applied in flight simulation systems and serve as a basis for further development of flight simulators
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
Corrosion inhibitors for prevention of corrosion in geothermal power plants equipment
No full textTema ovog rada su inhibitori korozije za zaštitu opreme u sustavima za proizvodnju geotermalne energije. Geotermalna energija, kao obnovljivi i održiv izvor, sve se više koristi za proizvodnju električne energije i industrijske procese, ali eksploatacija geotermalnih sustava donosi ozbiljne izazove u pogledu korozijske otpornosti materijala zbog visokih temperatura, tlakova i prisutnosti agresivnih medija poput kiselina, klorida i sumporovodika.
U teorijskom dijelu rada obrađeni su osnovni principi iskorištavanja geotermalne energije, vrste geotermalnih elektrana, zahtjevi za materijale koji se koriste u ekstremnim radnim uvjetima te tipovi korozijskih oštećenja koji se najčešće pojavljuju u takvim sustavima. Poseban naglasak stavljen je na mehanizme djelovanja inhibitora korozije, njihove klasifikacije, kemijski sastav i primjenu u svrhu produljenja vijeka trajanja opreme.
Eksperimentalni dio rada obuhvaća ispitivanja učinkovitosti inhibitora korozije na čelicima L80 i P110, koji se često koriste za proizvodnju bušotinskih cijevi. Ispitivanja su provedena u 15%-tnoj otopini HCL i HCL s dodatkom metanola pri 200 °C i 70 bara, u autoklavu Chandler 5617. Korišteni su inhibitori korozije na bazi dušika, a njihova učinkovitost je procijenjena metodom gubitka mase te su rezultati prikazani tablično.
Na temelju dobivenih podataka izrađene su preporuke za odabir inhibicijskog sustava te je u CAD programu modeliran dio sustava za transport fluida u geotermalnim elektranama, uzimajući u obzir brzinu korozije. Rezultati potvrđuju važnost odgovarajuće inhibicijske zaštite za produljenje radnog vijeka opreme i osiguranje ekonomske isplativosti eksploatacije geotermalne energije.The topic of this thesis is corrosion inhibitors used for protecting equipment in geothermal energy production systems. Geothermal energy, as a renewable and sustainable source, is increasingly utilized for electricity generation and industrial applications. However, its exploitation introduces significant material degradation challenges due to high temperatures, pressures, and the presence of aggressive media such as acids, chlorides, and hydrogen sulfide.
The theoretical part of the work covers the principles of geothermal energy use, types of geothermal power plants, material requirements for extreme conditions, and typical forms of corrosion damage. Particular focus is given to the mechanisms of corrosion inhibitor action, their classifications, chemical compositions, and applications for prolonging equipment service life.
The experimental section presents the investigation of corrosion inhibitor efficiency on L80 and P110 steels, commonly used for production tubing and casing. Tests were conducted in 15% HCl and HCl with methanol at 200 °C and 70 bar using a Chandler 5617 autoclave. Nitrogen-based inhibitors were used for corrosion inhibition. Corrosion rates were determined by mass loss measurements, and results were presented in tables.
Based on the results, recommendations for optimal inhibitor formulation were proposed, and a CAD model of a geothermal fluid transport section was created, integrating corrosion rate analysis. Findings confirm that appropriate corrosion inhibition significantly improves the durability of metallic components and supports the economic viability of geothermal exploitation
Synthesis and structural characterization of new quinoline and triazole derivatives with potential antitrypanosomal activity
No full textCilj ovog rada je sinteza novih derivata kinolina i triazola i njihovih Re(I) trikarbonilnih kompleksa te sinteza derivata kinolina i heterocikličkih hidrazona. Derivati kinolina i triazola (9a−9c, 10a, 11a−11c) dobiveni su mehanokemijskom sintezom kojom je provedena reakcija cikloadicije azida i alkina katalizirana Cu(I). Spojevi 9a i 10a nadalje su korišteni kao ligandi za kompleksiranje s Re(I) pentakarbonil-kloridom (9aRe, 10aRe). 2-(trifluormetil)kinolin-4-oli dobiveni su Conrad–Limpachovom ciklokondenzacijom te su, kao i 3-nitro-1,2,4-triazol, potom prevedeni u odgovarajuće alkine i azide. Klik reakcija alkina i azida provedena je primjenom azidnih kinolina i N-propargiliranog 1,2,4-triazola te korištenjem O-alkiliranih kinolina i azidnog triazola. Derivati kinolina i hidrazona (15a−15d, 16a−16d) dobiveni su nukleofilnom adicijom hidrazinskih kinolina na karbonilnu skupinu heterocikličkih aldehida, praćenom dehidratiranjem. Strukture spojeva potvrđene su spektroskopijom 1H i 13C NMR, karakteristične apsorpcijske vrpce potvrđene su IR spektroskopijom, a strukture derivata kinolina i hidrazona dodatno su potvrđene visokoučinkovitom spektrometrijom masa. Biološka ispitivanja novosintetiziranih spojeva (9a−9c, 10a, 11a−11c, 9aRe, 10aRe, 15a−15d, 16a−16d) su u tijeku.The aim of this work is the synthesis of novel quinoline and triazole derivatives as well as their Re(I) tricarbonyl complexes. Preparation of quinoline-based hydrazone derivatives was also performed. Quinoline triazole derivatives (9a−9c, 10a, 11a−11c) were synthesized by Cu(I)-catalyzed azide–alkyne cycloaddition using mechanochemistry. Compounds 9a and 10a served as ligands for complexation with Re(I) pentacarbonyl chloride, yielding metal complexes 9aRe and 10aRe. 2-(Trifluoromethyl)quinolin-4-ols were synthesized through Conrad–Limpach cyclocondensation, and together with 3-nitro-1,2,4-triazole, were transformed into corresponding alkynes and azides. Click reactions were performed by reaction of azido-substituted quinolines and N-propargylated 1,2,4-triazole, and O-alkylated quinolines and azido triazoles. Hydrazone derivatives (15a−15d, 16a−16d) were obtained via nucleophilic addition of quinoline hydrazines to the carbonyl group of heterocyclic aldehydes, followed by dehydration. The structures of the synthesized compounds were confirmed by ¹H and ¹³C NMR spectroscopy, characteristic absorption bands were identified by IR spectroscopy and the structures of the quinoline hydrazone derivatives were further confirmed by high resolution mass spectrometry. Biological evaluation of the newly synthesized compounds (9a−9c, 10a, 11a−11c, 9aRe, 10aRe, 15a−15d, 16a−16d) is currently underway
Assault Ramp for Urban Tactical Vehicle
No full textOklopni robotski sustav MV-3 Hystrix je višenamjensko daljinski upravljivo vozilo namijenjeno za pružanje potpore intervencijskih postrojbama prilikom izvođenja protuterorističkih operacija. Zbog svojih dimenzija može ga se koristiti unutar zatvorenih prostora i objekata te otvorenih prostora s uskim prolazima. Vozilo na sebi ima sklopive štitove pomoću kojih se može prilagoditi određenom zadatku.
Diplomski rad izrađen je u suradnji s tvrtkom DOK-ING d.o.o. zbog potrebe razvoja sustava za povišeni taktički ulazak na spomenutom vozilu. Izvedeno je projektiranje navalne rampe u formi alata koja može doseći visine prvog i drugog kata zgrade pri čemu je bilo potrebno osigurati sigurno kretanje najviše dvaju člana intervencijskih postrojbi. Provedeno je koncipiranje rampe i određenih funkcija rampe. Kao dodatna oprema na rampi su osigurani prihvati za dva štita, ljestve i uže. Provedeni su proračuni i izrađena je tehnička dokumentacijaThe MV-3 Hystrix armored robotic system is a multi-purpose remote-controlled vehicle intended to provide support to intervention units during counter-terrorist operations. Due to its dimensions, it can be used inside closed spaces and buildings, as well as open spaces with narrow passages. The vehicle has foldable shields with which it can be adapted to a specific task.
The diploma thesis was prepared in cooperation with the company DOK-ING d.o.o. due to the need to develop a system for elevated tactical entry on the vehicle. The design of an assault ramp in the form of a tool was carried out. The ramp needs to reach the heights of the first and second floors of a building, while ensuring safe movement of two members of the intervention units. There are insured mounts for additional equipment which are two shields, a ladder and a rope. Calculations were carried out and technical documentation was prepared
Investigation of change in water content of swollen donepezil loaded microspheres at simulated nasal conditions
No full textOsjetilni učinci povezani s primjenom lijekova putem nosa važan su aspekt pri razvoju novih oblika lijekova. Prevelika viskoznost gelova ima negativan utjecaj na mehanizam mukocilijarnog čišćenja što može narušiti homeostazu nazalne sluznice i dišnog sustava. Isušivanje i stvaranje filma također su potencijalne mane gelirajućih sustava i mogu uzrokovati iritaciju nosne sluznice i smanjiti adherenciju pacijenata. In vitro ispitivanje gubitka vode iz gela i kroz gel prvi je korak u predviđanju osjetilnih učinaka nakon primjene in situ gelirajućih praškastih sustava za nazalnu primjenu.
Cilj ovog rada bio je ispitati promjenu sadržaja vode pri simuliranim uvjetima nosne šupljine u izbubrenim mikrosferama kao nosačima donepezila, indiciranog u liječenju blage do umjerene Alzheimerove bolesti. Metodom sušenja raspršivanjem pripravljene su mikrosfere koje sadrže: (i) donepezil i kitozan (DK), (ii) donepezil, kitozan i manitol (DKM) te (iii) donepezil, kitozan i laktozu (DKL), i kontrolnim fizičkim smjesama DK mikrosfera s manitolom (DK+M) i laktozom (DK+L). Mikrosfere su uspješno pripravljene sušenjem raspršivanjem, a iskorištenje procesa iznosilo je 14,5 – 60,1 %. Postignuta je uspješnost uklapanja donepezila u rasponu 91,4 – 93,2 % te je sadržaj lijeka iznosio 4,6 – 4,7 %. Bubrenjem svih pripravljenih praškastih uzoraka u umjetnom nosnom fluidu pripravljeni su gelovi za provedbu ispitivanja gubitka vode iz gela i kroz gel, pri simuliranim uvjetima nosne šupljine. Imerzijska ćelija kao nosač gela, pokazala se prikladnom za provedbu predmetnih ispitivanja. Konzistencija gelova koji su u svom sastavu imali laktozu bila je dostatna samo za orijentacijska mjerenja ispitivanih parametara gubitka vode. Za sve gelove inkubirane tijekom 8,5 h pri temperaturi od 34°C i 90% relativne vlage, uočena je linearna ovisnost kumulativnog gubitka mase vode o vremenu: (i) iz gela iznad praznog spremišnog odjeljka imerzijske ćelije, (ii) iz gela iznad spremišnog odjeljka imerzijske ćelije koji sadrži vodu, i (iii) iz spremišnog odjeljka koji sadrži vodu, kroz gel. Najveća brzina isparavanja vode iz gela iznad praznog spremišnog odjeljka imerzijske ćelije (44,3 mg/h) i iznad spremišnog odjeljka koji sadrži vodu (38,5 mg/h) zabilježena je za gel pripravljen bubrenjem DK mikrosfera. Isti gel karakteriziran je i najizraženijim okluzivnim učinkom u usporedbi s drugim ispitivanim gelovima, što upućuje na promjenu strukture konvencionalnog kitozanskog gela uslijed dehidracije. Najveća sposobnost zadržavanja vode DKM gela pripisana je prisustvu manitola te upućuje na najmanju mogućnost isušivanja i stvaranja polimernog filma na nosnoj sluznici te, posljedično, na najmanji rizik od izazivanja iritacije nosne sluznice. Time su DKM mikrosfere procijenjene kao praškasti sustav s najvećim potencijalom za neiritabilnu nazalnu primjenu.Sensory effects associated with nasal drug administration represent an important aspect in the development of innovative drug formulations. Excessive gel viscosity can negatively affect the mucociliary clearance mechanism, potentially disrupting the homeostasis of the nasal mucosa and the respiratory system. Dehydration and film formation are also potential drawbacks of gelling systems, which may cause nasal mucosa irritation and reduce patient adherence. In vitro evaluation of water loss from and through the gel is the first step in predicting the sensory effects following the application of in situ gelling nasal powders.
The aim of this study was to investigate changes in water content under simulated nasal cavity conditions in swollen microspheres used as carriers for donepezil, a drug indicated for the treatment of mild to moderate Alzheimer's disease. Spray dryng method was employed to prepare microspheres containing: (i) donepezil and chitosan (DK), (ii) donepezil, chitosan and mannitol (DKM), and (iii) donepezil, chitosan and lactose (DKL). Additionally, physical mixtures of DK microspheres with mannitol (DK+M) and lactose (DK+L) were used as control samples. The microspheres were successfully prepared with process yields ranging from 14.5% to 60.1%. The entrapment efficiency of donepezil ranged from 91.4% to 93.2%, and drug content ranged from 4.6% to 4.7%. Gell were obtained by swelling of the prepared powder samples in artificial nasal fluid, and subsequently used to evaluate water loss from and through the gels under simulated nasal cavity conditions. The immersion cell used as a gel holder proved to be suitable for conducting the planned investigations. The consistency of gels containing lactose was sufficient only for indicative measurements of water loss parameters. For all gels incubated for 8.5 hours at 34°C and 90% relative humidity, a linear relationship was observed between cumulative water mass loss and time: (i) from the gel above the empty reservoir compartment of the immersion cell, (ii) from the gel above the reservoir compartment containing water, and (iii) from the reservoir compartment containing water, through the gel. The highest evaporation rate from the gel above the empty reservoir compartment (44.3 mg/h) and above the water-containing reservoir (38.5 mg/h) was recorded for the gel prepared by swelling of DK microspheres. This gel also showed the most pronounced occlusive effect compared to other tested gels, indicating structural changes in the conventional chitosan gel due to dehydration. The greatest water retention capacity of the DKM gel was attributed to the presence of mannitol, suggesting the lowest potential for dehydration and polymer film formation at the nasal mucosa and, consequently, the lowest risk of mucosal irritation. Based on these findings, DKM microspheres were recognized as the powder with the greatest potential for non-irritating nasal administration
Increasing the efficiency of machines in the process industry using Lean and Industry 4.0
No full textU ovom su radu obrađene moderne metodologije upravljanja proizvodnjom: Lean menadžment i Industrija 4.0, te je obrađen realni primjer iz proizvodnje s primjenom odabranih metoda. Uvodni dio rada sadržava povijest, odnosno razvoj Lean menadžmenta i Industrije 4.0 te osnovne principe i gubitke definirane Lean-om. Lean menadžment je filozofija upravljanja procesima (proizvodnim, ali i drugim) te obuhvaća širok spektar metodologija koje su se razvile kroz dugi niz godina. Također obrađene su najpoznatije i najčešće korištene metode poput SMED-a, 5S-a, VSM-a, Kaizen-a, TPM-a. Svaki Lean alat služi drugoj svrsi i može se koristiti u drugoj situaciji. Pa se tako 5S najčešće koristi za organizaciju radnog mjesta kako bi sav alat bio lako dostupan. SMED se primjenjuje za ubrzavanje izmjene alata dok proizvodnja stoji. VSM služi kako bi se grafički prikazao proces sa svim svojim stavkama i potprocesima što olakšava uočavanje gubitaka. Kaizen pristup organizira sistematičan način rješavana problema u timovima. U drugom dijelu rada obrađene su tehnologije koje pripadaju posljednjoj industrijskoj revoluciji zvanoj Industrija 4.0. Industrija 4.0 zbirni je naziv za najmodernije tehnologije koje se razvijaju i implementiraju u industriju (i drugdje). Takvih tehnologija je mnogo te se one kontinuirano unaprjeđuju. Obrađene su i najčešće i najpoznatije tehnologije poput Internet of Things, aditivne proizvodnje, izmijenjene stvarnosti. Internet of Things ponajprije služi povezivanju strojeva i omogućavanu njihove međusobne komunikacije. Aditivna proizvodnja naziva se još i 3D printanje te se u industriji koristi za brzu izradu prototipova. Izmijenjena stvarnost omogućava prikaz željenih elemenata u stvarnom vremenu dodanih u stvarnost kroz posebne naočale ili na druge načine. U posljednjem dijelu rada opisano je jedno proizvodno poduzeće te procesi koji se odvijaju unutar istog. Odabran je proces u poduzeću na kojem će biti prikazane odabrane metode Lean menadžmenta i tehnologije koje spadaju u početke procesa transformacije poduzeća u Industriju 4.0.This paper deals with modern production management methodologies: Lean management and Industry 4.0, as well as a real-life example from production with the application of selected methods. The introductory part of the paper contains the history, that is, the development of Lean management and Industry 4.0, as well as the basic principles and waste defined by Lean. Lean management is a philosophy of process management (production, but also other) and includes a wide range of methodologies that have been developed over many years. This work covers the well-known and most frequently used methods such as SMED, 5S, VSM, Kaizen, and TPM. Each Lean tool serves a different purpose and can be used in different situations. So 5S is most often used to organize the workplace so that all tools are easily accessible. SMED is applied to speed up tool changes while production is at a standstill. VSM graphically displays the process with all its items and sub-processes, which makes it easier to spot losses. The Kaizen approach organizes a systematic way of solving problems in teams. In the second part of the work, the technologies belonging to the last industrial revolution called Industry 4.0 are discussed. Industry 4.0 is a collective name for the most modern technologies that are developed and implemented in the industry (and elsewhere). There are many such technologies and they are continuously being improved. The paper deals with the most common and well-known technologies such as the Internet of Things, additive manufacturing, and altered reality. The Internet of Things primarily connects machines and enables their mutual communication. Additive manufacturing is also called 3D printing and is used in industry for rapid prototyping. Altered reality allows the display of desired elements in real-time added to reality through special glasses or in other ways. In the last part of the paper, one production company and the processes that take place within it will be described. A process has been selected in the company where selected methods of Lean management and technologies that belong to the beginnings of the process of transforming the company into Industry 4.0 will be presented
Analysis of media discourse regarding Islam in the case of news portal in Croatia
No full textOvaj rad analizira medijski diskurs o islamu u Hrvatskoj na primjeru tri hrvatska news portala: 24sata.hr, Index.hr i Večernji.hr. Svrha analize je dobiti uvid u medijsku prezentaciju i sliku islama u Hrvatskoj. Također, naglasak rada je na moći komunikacije odnosno diskursa pri formuliranju stavova pojedinaca. Hipoteza je kako je diskurs o islamu negativnog karaktera s pregršt predrasuda i stereotipa te kako je ovaj diskurs u svoj suštini izrazito rasistički. Istraživanje je provedeno na uzorku od 48 članaka sva tri portala u periodu od 1. siječnja do 30. lipnja 2017. Članci su odabrani upisom termina islam i muslimani u tražilice portala i analizirani kvalitativnom metodom kritičke analize diskursa. Rezultati su u slučaju 24sata.hr i Večernji hr. potvrdili osnovnu hipotezu u cijelosti, dok je u slučaju Index.hr potvrda hipoteze djelomična. Smatram kako razlozi ovakvog prikaza islama leže u geopolitičkim i ekonomskim interesima velesila, sukladno s korištenim teorijama.This paper analyzes media discourse about Islam in Croatia. Three Croatian news portals were analyzed: 24sata.hr, Index.hr and Večernji.hr. The purpose of the anlysis is to get insight into the media presentation of Islam in Croatia. Also one of the main themes of this paper is the power that communication or rather discourse has on the opinions of individuals. The main hypothesis is that the discourse about Islam has a negative character, that many stereotypes and types of prejudice are used and that this discourse is, in its essence, racist. The analysis was conducted on a sample of 48 news articles from all three portals in the period from January 1. until June 30. 2017. The articles are selected by typing Islam or Muslims in the portals search bars and analyzed using critical discourse analysis, a qualitative method. The results confirmed the hypothesis completely in the case of 24sata.hr i Večernji.hr and were partially confirmed in the case of index.hr. It is my opinion that the reason for portraying Islam in this way lay in the geopolitical, strategic and economic interests of superpowers as stated in the theory used