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WapAI posreduje kompeticiju kod rojenja i stvaranje biofilma Bacillus subtilis
No full textBacteria are unicellular organisms but nonetheless they engage in multicellular behaviours like swarming motility and biofilm formation. Essential for their survival in such communities are mechanisms responsible for cooperation and competition. Moreover, bacteria are able to discriminate between strains based on the relatedness and treat less related strains differently than those that are genetically identical (clones) or highly related. This behaviour, referred to as kin discrimination, has been recently described for environmental strains of Bacillus subtilis and the tRNase toxin WapA has been identified as a potential kin discrimination locus. However, the mechanisms behind this process are not sufficiently known. Here, we characterize a role of the WapAI toxin-immunity system in competition between isogenic or non-kin strains. We studied their interactions in pellicles and swarming communities by determining their fitness by colony forming units. We also documented spatial distribution of two types of cells in pellicles by confocal microscopy. Our results show that the fitness of the toxin sensitive strain is significantly reduced compared to the toxin producing strain, regardless whether it is competed against parental or non-kin strain during swarming. In pellicles, parental strain did not outcompete the isogenic wapAI mutant, but the fitness of the non-kin mutant was reduced. Interestingly, mutant and parental cells co-aggregated into larger patches while two differentially labelled but otherwise isogenic strains mixed very well. Patchiness was not observed in non-kin combination, where the wild type outcompeted the mutant strain, which was undetectable by fluorescent microscopy. We conclude that competition in swarms is fiercer than in pellicles, probably due to less intense mixing of genotypes in pellicles.Bakterije su jednostanični organizmi koji stupaju u višestanične interakcije kao što su rojenje (engl. swarming) i formacija biofilmova. Za njihovo preživljenje u spomenutim zajednicama su nužni mehanizmi odgovorni za kooperaciju i kompeticiju. Nadalje, bakterije imaju sposobnost diskriminacije (razlikovanja) sojeva na temelju povezanosti gdje manje srodne sojeve tretiraju drugačije od genetički identičnih sojeva (klonovi) ili visoko srodnih. Spomenuto ponašanje se naziva diskriminacija srodnika (engl. kin discrimination), nedavno opisano u okolišnim sojevima bakterije Bacillus subtilis, a toksin WapA (tRNaza) kao potencijalni lokus za navedenu diskriminaciju. Međutim, mehanizmi iza ovog procesa nisu dovoljno znani. U ovom radu smo opisali ulogu WapAI sistema u kompeticiji između izogenih ili nesrodnih sojeva. Proučavali smo interakcije u peliklima i u zajednicama rojenja brojanjem kolonija na ploči (engl. colony forming units, CFU). Istražili smo prostornu distribuciju dvije vrste stanica u peliklima konfokalnom mikroskopijom. Rezultati su pokazali da je sposobnost razmnožavanja soja osjetljivog na toksin značajno smanjena u usporedbi sa sojem koji stvara toksin bez obzira je li u kompeticiji s roditeljskim ili nesrodnim sojem tijekom rojenja. U peliklima, roditeljski soj nije prevladao izogenu wapAI mutantu, ali je frekvencija nesrodne mutante bila značajno reducirana. Također, stanice mutante i roditeljskog soja su agregirale u veće nakupine dok su različito obilježeni, ali izogeni sojevi iskazali vrlo dobro miješanje. Nakupljanje stanica nije bilo zabilježeno u nesrodnim kombinacijama, gdje je divlji tip prevladao mutantu koju nije bilo moguće zapaziti fluorescentnim mikroskopom. Zaključno, kompeticija tijekom rojenja je snažnija nego u peliklima vjerojatno zbog slabijeg miješanja genotipova u peliklima
Redesign of the Impactor for Total Hip Arthroplasty
No full textThis master's thesis demonstrates the proper approach to problem-solving by carefully evaluating all the details and establishing guidelines in collaboration with surgeons to create the best product on the market. The foundation of this project was laid by compiling a list of functions, requirements, and desires with the help of expert reports and surgeon feedback after brainstorming, sketching different ideas, and exploring various options to improve the current impactor or develop a new solution. However, it was determined that the current version would require too much work to optimize and would not fulfill the demands as some other designs might. Therefore, a new idea was developed by observing competitors and creating a similar but different solution compatible with the shape of EcoFit 2M implants. After numerous prototypes and iterations, the redesign addressed all the functions, requirements, and wishes set at the beginning of this task and objectively made an excellent instrument, the impactor for total hip arthroplasty, hopefully improving the quality and outcomes of orthopedic surgeries
Hydrological Analysis of Spring Flow on the Left Bank of Cetina: Rumin Mali, Rumin Veliki and Ruda Velika : Undergraduate Thesis
No full textU ovom završnom radu statički su obrađeni hidrološki podaci protoka izvora na lijevoj obali rijeke Cetine: Rumin Mali, Rumin Veliki i Ruda Velika, te meteorološki podaci oborina za postaju Livno za razdoblje od 1.1.2008.-31.12.2014. godine. Na temelju tih podataka izrađena je krivulja trajanja i krivulja učestalosti. Za izvore Rumin Mali, Rumin Veliki i Ruda Velika zadani su podaci od 2008.-2014. godine. Na temelju tih podataka napravljena je krivulja trajanja za svaki izvor kao i dnevne, mjesečne i godišnje korelacijske veze između oborina Livna i zadanih izvora, kao i izvora međusobno.In this final paper, the hydrological data of the flow of springs on the left bank of the Cetina River: Rumin Mali, Rumin Veliki, and Ruda Velika, and meteorological precipitation data for the station Livno for the period from 1.1.2008 to 31.12.2014 were statically processed. year. Based on these data, a duration curve and a frequency curve were created. For the springs Rumin Mali, Rumin Veliki, and Ruda Velika, the data from 2008-2014 is given. year. Based on these data, a duration curve was created for each source, as well as daily, monthly, and annual correlations between the Livno precipitation and the given sources, as well as between the sources
CO2 Emissions in the Operation of Construction Machinery for Earthworks : Undergraduate Thesis
No full textEmisije ugljikovog dioksida izazivaju značajan interes u istraživanju građevinske industrije zbog sve veće svijesti o učincima klimatskih promjena. Građevinarstvo je prepoznato kao jedan od ključnih sektora u Europskom zelenom planu čiji je cilj da do 2050. više nema neto emisija stakleničkih plinova. Ovaj rad analizira faktore koji utječu na emisije CO2 kod građevinskih strojeva za zemljane radove, kao što su vrsta goriva, oprema, operativni i gradilišni faktori. Na temelju učinkovitosti strojeva, prikazani su proračuni emisija CO2 te konkretni primjeri proračuna za rad bagera. Rad također ističe važnost smanjenja emisija CO2 kroz optimizaciju rada i održavanje građevinskih strojeva.Carbon dioxide emissions are a significant concern in construction industry research due to the growing awareness of climate change impacts. Construction is recognized as one of the key sectors in the European Green Deal, which aims to achieve net-zero greenhouse gas emissions by 2050. This work analyzes the factors affecting CO2 emissions from earthwork construction machinery, including fuel type, equipment, operational, and site factors. Based on machine efficiency, calculations of CO2 emissions are presented, along with specific examples of calculations for excavator operations. This work also highlights the importance of reducing CO2 emissions through the optimization and maintenance of construction machinery
Numeričko modeliranje strujanja nenjutnovskog fluida tijekom punjenja baterijskog modula
No full textDuring operation, electric vehicle components experience shocks and vibrations that can potentially damage cells within the battery pack. Foam encapsulation enhances the structural integrity of battery pack by securing cells in place, shielding them from potential damage. Structural foams undergo several distinct stages, including the flow of non-Newtonian fluid, curing and foaming before reaching a final stable stage. The main aim of this thesis was to develop a method for numerically modeling the pouring of non-Newtonian fluid into the battery pack. The flow is laminar, transient and the Volume of Fluid (VoF) method is employed to model a multiphase flow and free surface between phases. Three models were analyzed: model with two dispensers, model with one dispenser, and model with different gap size between cells and other components. The detailed investigation of non-Newtonian fluid flow during the filling of the battery pack is performed to determine the fluid distribution within the domain, which is prerequisite for uniform foam encapsulation. All numerical calculations were conducted using the computational fluid dynamics software ANSYS Fluent.Prilikom vožnje, komponente električnih vozila izložene su udarcima i vibracijama koje mogu oštetiti ćelije unutar baterijskog paketa. Enkaspulacija pjenom povećava čvrstoću baterijskog paketa tako što osigurava ćelije na mjestu i štiti ih od mogućih oštećenja. Strukturne pjene prije formiranja stabilne faze moraju proći kroz nekoliko različith faza kao što su stvrdnjavanje i formiranje pjene uključujući i strujanje nenjutnovskog fluida. Glavni cilj ovog rada je razviti metodu za numeričko modeliranje ulijevanja nenjutnovskog fluida u baterijskom paketu. Strujanje je laminarno, nestacionarno i korištena je Volume of Fluid (VoF) metoda za modeliranje višefaznog strujanja i slobodne površine između različith faza. Analizirana su tri modela: model s dva dozatora, model s jednim dozatorom i model s različitim veličinama zazora između ćelija i ostalih komponenti. Detaljno istraživanje protoka nenjutnovkse tekućine tijekom punjenja baterijskog paketa provodi se kako bi se odredila distribucija tekućine unutar domene, što je preduvjet za jednoliku enkapsulaciju pjenom. Svi numerički proračuni provedeni su u programskom paketu za računalnu dinamiku fluida, ANSYS Fluent
Review and analysis of battery production process
No full textTema ovog diplomskog rada je prikaz i analiza tehnoloških procesa linije za proizvodnju baterija. U prvom dijelu rada definiran je pojam tehnološkog procesa, svrha i značaj u proizvodnom procesu. Definirana su vremena preko kojih se određuje vrijeme izrade proizvoda. Također su u prvom dijelu rada navedeni i objašnjeni osnovni pojmovi vezani za baterije za električno vozilo. Praktični dio rada proveden je u poduzeću Rimac Technology. U radu je dan opis poduzeća te je prikazan proizvodni program. Iz proizvodnog programa odabran je reprezentant za kojeg je napravljena analiza tehnoloških procesa proizvodne linije. Također je izrađen simulacijski model trenutnog procesa, a na temelju rezultata simulacije dani su prijedlozi unaprjeđenja. Na kraju je izrađen novi simulacijski model s prijedlozima unaprjeđenja za validaciju istih.The topic of this Master thesis is review and analysis of battery technological processes. In the first part of the paper, the concept of technological process is defined with it's purpose and significance. Times used to determine product build time are defined. Also, in the first part of the paper basic terms regarding batteries for electric vehicles are listed and explained. The practical part was carried out in the company Rimac Technology. In the paper, company and it's production program are described. A representative of production program was selected for which analysis of technological processes was made. A simulation model of current process was created and based on the results of simulation, suggestions for improvement were given. New model with improvement suggestions is created for validation of mentioned improvement suggestions
Imunološkim sustavom posredovana regulacija metabolizma aminokiselina tijekom virusnih infekcija
No full textIn response to viral infections, the body uses a wide range of immune mechanisms to protect itself from the invading pathogen. Moreover, in a recent decade it has been appreciated that immune cell signals play a significant part in the regulation of the metabolism and that they are implicated in the development of the various metabolic diseases. In addition, recent studies showed that immune-endocrine interactions have a crucial role in the maintenance of the host physiology and defense. However, the interorgan processes by which immune cells communicate with endocrine cells to coordinate endocrine function and thus to modulate amino acid metabolism during viral infections remains largely unclear. Moreover, what is the purpose of these changes remains fundamentally unexplored. Therefore, our hypothesis is that, in order to minimize the risk of excessive tissue damage and to prevent virus replication, the immune system actively modifies the metabolism of amino acids which boots immune response. Indeed, our research revealed that the immune system during viral infections actively modulates amino acids metabolism, and in particular axis of the homocysteine and cysteine levels. Moreover, we showed that targeting this metabolic pathway helps to modulate the immune response and thus control viral infections. Finally, we confirmed that monitoring and manipulating homocysteine/cysteine levels could be a potential strategy for treatment of viral infections. Therefore, the findings of this thesis will help to clarify the specific mechanisms by which homocysteine and cysteine metabolism regulate immune cell function, cytokine production, and viral replication.Kao odgovor na virusne infekcije, tijelo koristi širok spektar imunoloških mehanizama kako bi se zaštitilo od invazivnih patogena. U posljednjem desetljeću prepoznato je da signalizacija imunoloških stanica igra značajnu ulogu u regulaciji metabolizma, te je uključena u razvoj raznih metaboličkih bolesti. Štoviše, nedavne studije pokazale su da imunološko-endokrine interakcije imaju ključnu ulogu u održavanju fiziologije domaćina i obrambenih mehanizama. Međutim, međustanični mehanizmi kojima imunološke stanice komuniciraju s endokrinim stanicama kako bi koordinirale endokrinu funkciju i time modulirale metabolizam aminokiselina tijekom virusnih infekcija, ostaju uglavnom nejasni. Nadalje, svrha ovih promjena ostaje sveobuhvatno neistražena. Stoga je naša hipoteza da imunološki sustav, u cilju smanjenja rizika od prekomjernog oštećenja tkiva i suzbijanja replikacije virusa, aktivno mijenja metabolizam aminokiselina čime se pojačava imunološki odgovor. Naše istraživanje pokazalo je da imunološki sustav tijekom virusnih infekcija aktivno modulira metabolizam aminokiselina, a posebice razine homocisteina i cisteina. Dodatno smo pokazali da ciljanje ovog metaboličkog puta pomaže modulaciji imunosnog odgovora, a time i nadzoru virusne infekcije. Konačno, potvrdili smo da praćenje i manipuliranje razinama homocisteina i cisteina može biti potencijalna strategija za liječenje virusnih infekcija. Rezultati ovog istraživanja pomoći će razjasniti specifične mehanizme putem kojih metabolizam homocisteina i cisteina regulira funkcionalnost imunoloških stanica, proizvodnju citokina i replikaciju virusa
Review and analysis of the technological process for production of insulating component for transformers
No full textOvaj diplomski rad detaljno opisuje proizvodni proces jednog od proizvoda poduzeća. Na početku rada prikazani su izolacijski materijali i njihova uloga u transformatorima kao i teorijski uvod u projektiranje tehnoloških procesa. Opisano je poduzeće, njegova djelatnost, lokacija, organizacijska struktura te proizvodni program. U nastavku rada prikazan je raspored strojeva na jednoj od lokacija poduzeća kao i vrste proizvoda koji se tamo proizvode. Detaljno je prikazan proizvodni proces jednog od proizvoda – izolacijske komponente, zajedno s rasporedom operacija izrade. Glavni dio rada uključuje detaljan prikaz procesa izrade izolacijske komponente, od izuzimanja sirovine do pakiranja. Završni dio rada obuhvaća analizu vremena izrade, na temelju koje su predložena moguća poboljšanja procesa s ciljem povećanja produktivnosti i smanjenja vremena izrade.This thesis provides a detailed description of the production process for one of the company’s products. At the beginning of the thesis, insulating materials and their role in transformers are presented, along with a theoretical introduction to the design of technological processes. The company, its activities, location, organizational structure, and production program are described. The following section presents the layout of machines at one of the company's locations, as well as the types of products produced there. The production process for one of the products, an insulation component, is described in detail, along with the sequence of manufacturing operations. The main part of the thesis includes a comprehensive overview of the process of manufacturing the insulation component, from the handling of raw materials to packaging. The last part of the thesis includes an analysis of production time, based on which possible process improvements are proposed with the aim of increasing productivity and reducing manufacturing time
Real-time driver state detection
No full textU ovom će se radu dati potencijalno rješenje za problem automatskog prepoznavanja stanja vozača u stvarnom vremenu, koristeći napredne tehnologije za analizu i detekciju lica. Cilj je razviti sustav koji može detektirati različite aspekte stanja vozača kao što su pospanost, ometenost ili promjene u fokusu pažnje vozača, te na temelju tih podataka pravovremeno upozoriti vozača, a daljnjim razvojem i integracijom tehnologije s vozilom čak i poduzeti automatske sigurnosne mjere poput sigurnosnog zaustavljanja vozila.This paper proposes a potential solution to the problem of real-time automatic driver state recognition using advanced facial analysis and detection technologies. The goal is to develop a system capable of detecting various aspects of a driver’s state, such as tiredness, distraction, or changes in attention, and providing timely alerts based on this data. With further development and integration with the vehicle, the system could even implement automatic safety measures, such as safely stopping the vehicle
Categorization of fuel from waste
No full textProizvodnja otpada kontinuirano raste diljem svijeta, što predstavlja sve veći izazov za okoliš, društvo i gospodarstvo. Istovremeno, postaje sve važnije osigurati pristup održivoj energiji koja je dostupna svima. U ovom kontekstu, Waste-to-Energy (WtE) tehnologija, koja omogućuje konverziju otpada u energiju, predstavlja učinkovito rješenje za ove izazove. Otpad često sadrži komponente s visokim energetskim potencijalom koje se mogu iskoristiti za proizvodnju goriva. Time se ne samo smanjuje količina otpada koja završava na odlagalištima, već se otpad koristi kao vrijedan resurs. WtE tehnologija također pridonosi ostvarenju ciljeva kružnog gospodarstva jer potiče kružni tok materijala i energije. Umjesto jednostavnog odbacivanja otpada, ovaj pristup omogućuje njegovu pretvorbu u korisno gorivo. Kroz kategorizaciju goriva dobivenog iz različitih vrsta otpada, postiže se pravilno upravljanje otpadom, identifikacija energetskog potencijala materijala te određivanje najprikladnijih postupaka obrade i korištenja. Ova praksa osigurava da se proizvedeno gorivo iz otpada ispunjava specifične zahtjeve i da se koristi na način koji je u skladu s relevantnim smjernicama i propisima. Cilj ovog završnog rada je pružiti dublje razumijevanje kategorizacije goriva iz otpada, istražiti njezinu ulogu u održivom gospodarenju otpadom te analizirati izazove i poteškoće s kojima se susrećemo prilikom kategorizacije goriva iz otpada i njegove prakse korištenja.The production of waste is continuously increasing worldwide, presenting a growing challenge for the environment, society, and the economy. At the same time, it is becoming increasingly important to ensure access to sustainable energy that is available to everyone. In this context, Waste-to-Energy (WtE) technology, which enables the conversion of waste into energy, represents an effective solution to these challenges. Waste often contains components with high energy potential that can be utilized for fuel production. This not only reduces the amount of waste ending up in landfills but also uses waste as a valuable resource. WtE technology also contributes to achieving circular economy goals by promoting the circular flow of materials and energy. Instead of simply discarding waste, this approach allows for its conversion into useful fuel. Through the categorization of fuel derived from different types of waste, proper waste management is achieved, the energy potential of materials is identified, and the most appropriate processing and utilization methods are determined. This practice ensures that the produced fuel from waste meets specific requirements and is used in a manner consistent with relevant guidelines and regulations. The aim of this final paper is to provide a deeper understanding of the categorization of fuel from waste, explore its role in sustainable waste management, and analyze the challenges and difficulties encountered in the categorization of fuel from waste and its practical use