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BIOMONITORING OF METALS IN ENVIRONMENT AND HONEY BEE COLONIES (Apis mellifera L.)
No full textOvo znanstveno istraživanje obuhvaća ispitivanje specifičnih pokazatelja onečišćenja, konkretno teških i toksičnih metala i metaloida, prisutnih u sastavnicama okoliša (u vodi i tlu) te njihovu prisutnost u biljnom materijalu kao i u pčelinjim zajednicama Apis mellifera L. (u odraslim pčelama i medu). Medonosne pčele su vrlo osjetljivi organizmi i pouzdani bioindikatori onečišćenja. Uzorci su uzimani s 20 lokacija na području triju regija Republike Hrvatske, u kontinentalnom nizinskom dijelu, primorskom dijelu i gorskom dijelu. Lokacije su vezane uz intenzivnu poljoprivrednu proizvodnju, urbano područje i prometnu gustoću, industrijsko područje te šumsko područje i područje uz more. Određivani su metali i metaloidi: As, Cd, Co, Cr, Cu, Hg, Fe, Mn, Ni, Pb, Se i Zn. Navedeni elementi analizirani su na atomskom apsorpcijskom spektrometru (AAS) odnosno induktivno spregnutom plazmom s masenom spektrometrijom (ICP-MS). Dobiveni rezultati uspoređeni su s postojećim propisima o kvaliteti vode, tla i meda, a izrađena je i korelacijska analiza prisutnih onečišćivala u okolišu i pčelinjim zajednicama. Antropogeni otisak odnosno pritisak na okoliš i pčele izražen je u vidu faktora bioakumulacije, indeksa kvalitete i ukupnog pokazatelja antropogenog utjecaja.This scientific research includes analysis of specific indicators of contamination, heavy and toxic metals and metalloids, present in the components of the environment (water and soil) and their presence in plant material as well as in honey bee colonies Apis mellifera L. (in adult honey bees and honey). Honey bees are very sensitive organisms and reliable bioindicators of environmental contamination. Samples were taken from 20 locations in three regions of the Republic of Croatia, in the continental lowland region, the coastal region and the mountain region. The locations are related to intensive agricultural production, urban area and transport activity, industrial area, forest area and near the sea coast. The following metals and metalloids were determined: As, Cd, Co, Cr, Cu, Hg, Fe, Mn, Ni, Pb, Se and Zn. These elements were analysed on atomic absorption spectrometer (AAS) and inductively coupled plasma with mass spectrometry (ICP-MS). A correlation analysis of the present contaminants in the environment and honey bee colonies was made. The obtained results were compared with the existing regulations on the quality of water, soil and honey, and a correlation analysis of the contaminants present in the environment and honey bee colonies was made. The anthropogenic footprint, i.e. anthropogenic pressure on the environment and honey bees, is expressed in the form of bioaccumulation factors, quality index and total indicator of anthropogenic impact
THE ROLE OF IQGC PROTEIN IN THE REGULATION OF ADHESION IN DICTYOSTELIUM DISCOIDEUM PROTIST
No full textProtein IqgC iz protista Dictyostelium discoideum dijeli svojstva proteina iz skupina IQGAP i
RasGAP te regulira endocitozu deaktivacijom male GTPaze RasG. Cilj ovog rada je
karakterizacija dodatne uloge proteina IqgC u regulaciji stanične adhezije. Testovima adhezije
pokazala sam da stanice mutanta iqgCimaju defekt u pričvršćivanju za podlogu. Ekspresijom
skraćenih varijanti proteina IqgC u stanicama iqgCutvrdila sam da je za normalnu adheziju
nužna prisutnost obje domene proteina, domene RGCt i domene GAP. Korištenjem
mikroskopije TIRF ustanovila sam da je protein IqgC lokaliziran u fokalnim adhezijskim
strukturama, gdje ga navodi domena RGCt. Biokemijskim pokusima i metodom BiFC
ustanovila sam da protein IqgC veže malu GTPazu RapA. Analizom kretanja stanica otkrila
sam anomalije u nasumičnom kretanju i kemotaksiji stanica mutanta iqgC-
, vjerojatno
posredovane deregulacijom aktivnosti GTPaza RasG i RapA. Analizom lokalizacije i
aktivnosti proteina IqgC u staničnim sojevima deficijentnim za razne proteine regulatore
adhezije identificirala sam signalni put reguliran proteinom RapA unutar kojeg protein IqgC
djeluje kao pozitivni regulator adhezije.IqgC protein from the protist Dictyostelium discoideum shares the properties of IQGAP and
RasGAP proteins and regulates endocytosis by deactivating small GTPase RasG. The goal of
this work is an investigation of an additional role of IqgC in the regulation of adhesion. Using
adhesion assays, I showed that mutant iqgCcells attach poorly to the substratum. Rescue
experiments with truncated variants of IqgC showed that both RGCt and GAP domains are
necessary for normal adhesion. Using TIRF microscopy, I established that IqgC is localized in
focal adhesion structures and that the RGCt domain is responsible for its proper localization.
Biochemistry and BiFC experiments identified an interaction between IqgC and RapA.
Migration assays detected anomalies in random motility and chemotaxis of iqgCcells, likely
mediated by deregulation of RasG and RapA signaling. By testing the localization and
activity of the IqgC protein in cell strains deficient for various adhesion regulators, I
identified a signaling pathway regulated by RapA where IqgC acts as a positive regulator of
cell adhesion
Modeli isplativosti proizvodnje vodika i njegove integracije u plinsku mrežu
No full textIn the energy transition, hydrogen is considered one of the key elements that could
enable the realization of a carbon-neutral economy by 2050. The research within this
doctoral thesis includes an analysis of the profitability of building an electrolyzer for
the production of yellow and green hydrogen, making maximum use of the existing
infrastructure. The goal is to formulate models that will analyze the potential location
of an unpromising thermal power plant, the location of a wind power plant located
near the gas transportation network, and the location of a large hydrogen consumer.
The production price and quantity of hydrogen as output variables of the models will
test the hypothesis about the impact of hydrogen in the energy transition in terms of
reduced CO2 emissions and utilization of the existing gas infrastructure.
Two economic models investigate the possibility of integrating hydrogen into the gas
network, i.e. the first model analyzes the justification of investing in an electrolyzer
at the location of the thermal power plant, and the second model analyzes the impact
of hydrogen production on the total income of the wind power plant. An alternative
to the integration of hydrogen into the gas network is a third economic model that
calculates the justification of hydrogen production at the point of consumption, i.e. a
model where electricity is transmitted to the point of hydrogen consumption, instead
of transporting hydrogen through the gas system.
Economic models represent a tool that enables the comparison of the production
price of hydrogen with the prices of fossil alternatives. If the production price of
hydrogen is uncompetitive, the share of necessary subsidies is calculated in terms
of the justification of the investment and the achievement of decarbonization goals.
The research results will provide new scientific insights and help in making
investment and regulatory decisions on investing in hydrogen production by water
electrolysis for greater utilization and efficiency of the existing energy infrastructure,
while respecting the goals of climate neutrality.U energetskoj tranziciji vodik se smatra jednim od ključnih elemenata koji bi mogao
omogućiti ostvarenje ugljično-neutralnog gospodarstva do 2050. godine. Istraživanje
u okviru ovog doktorskog rada obuhvaća analizu isplativosti izgradnje elektrolizatora
za proizvodnju žutog i zelenog vodika maksimalno iskorištavajući postojeću
infrastrukturu. Cilj je formulirati modele koji će analizirati potencijalnu lokaciju
neperspektivne termoelektrane, zatim lokaciju vjetroelektrane koja se nalazi u blizini
plinske transportne mreže te lokaciju velikog potrošača vodika. Proizvodna cijena i
količina vodika kao izlazne varijable modela testirat će hipotezu o utjecaju vodika u
energetskoj tranziciji glede smanjena emisija CO2 i iskorištvanja postojeće plinske
infrastrukture.
Dva ekonomska modela istražuju mogućnost integracije vodika u plinsku mrežu,
odnosno prvi model analizira opravdanost ulaganja u elektrolizator na lokaciji
termoelektrane, a drugi model analizira utjecaj proizvodnje vodika na ukupni prihod
vjetroelektrane. Alternativa integraciji vodika u plinsku mrežu je treći ekonomski
model koji izračunava opravdanost proizvodnje vodika na mjestu potrošnje, odnosno
model gdje se električna energija prenosi do mjesta potrošnje vodika, umjesto
transporta vodika plinskim sustavom.
Ekonomski modeli predstavljaju alat koji omogućuje usporedbu proizvodne cijene
vodika sa cijenama fosilnih alternativa. Ukoliko je proizvodna cijena vodika
nekonkurentna, izračunava se udio potrebnih subvencija u pogledu opravdanosti
ulaganja i ostvarenja dekarbonizacijskih ciljeva.
Rezultati istraživanja pružiti će nove znanstvene uvide te pomoći pri donošenju
investicijskih i regulatornih odluka o ulaganju u proizvodnju vodika elektrolizom vode
za veću iskoristivost i učinkovitost postojeće energetske infrastrukture, uvažavajući
pritom ciljeve klimatske neutralnosti
The history of Lika's schooling until 1918
No full textSvrha ovog istraživanja leži u činjenici da povijest školstva Like koja cjelovito prikazuje i objedinjuje začetke i razvoj školstva do 1918. do danas nije napisana. U ovome radu donesen je cjeloviti povijesni pregled školstva na prostoru Like od osnivanja prvih škola dvadesetih godina 18. st. do 1918., te istražen i predstavljen njegov utjecaj na razvoj kulturno-društveno gospodarskog života u Lici. U radu je korištena povijesna metoda. Početna etapa istraživanja obuhvatila je upoznavanje i prikupljanje izvora te stvaranje dokumentarne i faktografske osnove nakon čega je uslijedila obrada izvora, utvrđivanje činjenica, njihova sistematizacija te utvrđivanje i interpretacija kauzalnih veza. S obzirom na veliki broj prikupljenih brojčanih podataka, oni su prikazani tablično. Pri obradi brojčanih podataka koristila se statistička obrada (brojčani odnosi i postotci) koja je omogućila otkrivanje tendencija razvitka školstva Like. Povijesnom sintezom, kao metodom zaključivanja i izlaganja, utvrđen je pregled stanja ličkog školstva do 1918. godine, na temelju čega je donesen zaključak. Rad je obuhvatio pregled svih škola koje su radile na području Like u navedenom razdoblju s obzirom na njeno upravno teritorijalno uređenje te su opisane i analizirane tadašnje školske prilike. Provedeno istraživanje upućuje na zaključak da je razvoj školstva u Lici utjecao i na razvoj kulturno-društveno gospodarskog života na ličkom prostoru, ali je i posebnost ličkog prostora (teritorijalno političko i upravno ustrojstvo, prirodne i geografske značajke) utjecala na razvoj školstva u Lici. Značajnu ulogu u početnom opismenjavanju puka u Lici imali su crkveni redovi, no temelj razvoju školstva Like postavili su doneseni školski zakoni i odredbe za vrijeme austrijske vlasti. Njihovim donošenjem uređuje se i organizira javno, državno školstvo na ovom području. Otvaraju se škole, zapošljava učiteljski kadar, određuje nastavni sadržaj, metode, itd. Posebna pažnja u ovom radu posvećena je učiteljskom kadru ličkih škola jer su oni činili motor zamašnjak svekolikog razvoja Like. S obzirom na prioritetnu ulogu u razvoju školstva, naglašena je uloga Gospića koji je bio respektabilno obrazovno središte sa najvećim izborom škola u Lici neovisno je li riječ o osnovnom ili višem obrazovanju o čemu svjedoči broj i vrste škola koje su radile u Gospiću. Najveći značaj imala je Gimnazija u Gospiću, zasigurno elitna obrazovna institucija Like prema kvaliteti učiteljskog kadra koji je tada u njoj radio, ali i učeničkoj inteligenciji koju je okupljala. U njoj su radili i polazili je brojni značajni predstavnici tadašnjeg i kasnijeg kulturnog, društvenog, umjetničkog, znanstvenog i gospodarskog napretka Like i Hrvatske, a neki od njih su svojom djelovanjem ostvarili nemjerljiv svjetski doprinos što je u ovom radu prikazano.The purpose of this research lies in the fact that the history of education in Lika, which fully shows and unifies the beginnings and development of education up to 1918, has not been written to date. In this paper, a complete historical review of education in the area of Lika from the establishment of the first schools in the twenties of the 18th century to 1918 was made, and its influence on the development of cultural, social and economic life in Lika was investigated and presented. The historical method was used in the paper. The initial stage of the research included getting to know and collecting sources and creating a documentary and factual basis, which was followed by the processing of sources, the establishment of facts, their systematization and the establishment and interpretation of causal links. Considering the large number of numerical data collected, they are presented in a table. When processing numerical data, statistical processing (numerical ratios and percentages) was used, which made it possible to reveal the tendencies of the development of the Lika school system. Through historical synthesis, as a method of conclusion and presentation, an overview of the state of education in Lika until 1918 was established, on the basis of which a conclusion was made. The paper included an overview of all schools that worked in the area of Lika in the mentioned period with regard to its administrative-territorial arrangement, and school conditions at that time were described and analyzed. The conducted research leads to the conclusion that the development of education in Lika also influenced the development of cultural, social and economic life in the Lika area, but the uniqueness of the Lika area (territorial-political and administrative structure, natural and geographical features) also influenced the development of education in Lika. Church orders played a significant role in the initial literacy of the regiment in Lika, but the foundation for the development of education in Lika was laid by the school laws and regulations passed during the Austrian rule. By adopting them, public, state education in this area is regulated and organized. Schools are opened, teaching staff is hired, teaching content, methods are determined, etc. Special attention in this paper is devoted to the teaching staff of Lika schools because they were the flywheel engine of all Lika's development. With regard to the priority role in the development of education, the role of Gospić was emphasized, which was a respectable educational center with the largest selection of schools in Lika, regardless of whether it is primary or higher education, as evidenced by the number and types of schools that worked in Gospić. The greatest significance was the Gymnasium in Gospić, certainly an elite educational institution in Lika, according to the quality of the teaching staff that worked there at the time, but also the student intelligence that it gathered. Many important representatives of the then and later cultural, social, artistic, scientific and economic progress of Lika and Croatia worked and went there, and some of them made an immeasurable global contribution through their activities, which is shown in this work
The Success of the Development of Social Competences and Self- Concept of Typically Developing Students During Primary School Subject Classes with Children with Disabilities
No full textUključivanje učenika s teškoćama u razvoju uz izradu individualiziranih kurikuluma u redovne osnovne škole predstavlja mnoge mogućnosti i izazove u inkluzivnom odgojno-obrazovnom okruženju. Uspoređujući različite prakse uključivanja, postaje očito da neke strategije daju pozitivne rezultate, dok druge ne uspijevaju radi nedostatka pripreme i podrške. Suprotstavljena iskustva uspješne i neuspješne inkluzije naglašavaju potrebu za istraživanjem značaja inkluzije za razvojna postignuća učenika. Ovom se disertacijom želi doprinijeti uspješnosti provedbe modela odgojno-obrazovne inkluzije s obzirom na značaj socijalnih i razvojnih postignuća učenika tipičnoga razvoja te na osnovu toga razviti model pripreme učenika tipičnoga razvoja za uspješno svladavanje inkluzivnih zadataka. Interes je ove disertacije istražiti značenje socijalnih kompetencija, samopoimanja i psihološke autonomije učenika tipičnoga razvoja za uspješno provođenje modela inkluzivnog uključivanja učenika s teškoćama (uz individualizirane kurikulume) u redovite razrede predmetne nastave te značenje tog iskustva za razvojna postignuća učenika tipičnoga razvoja. Glavni je cilj istraživanja znanstveno valjanim pristupom ustanoviti uspješnost razvoja socijalnih kompetencija i samopoimanja učenika tipičnoga razvoja te ulogu i značenje uspješnosti razvoja ovih postignuća učenika tipičnoga razvoja u realizaciji inkluzivnih zadataka izgradnje bliskih i prijateljskih odnosa s vršnjacima s teškoćama. Uspješnost modela inkluzije tijekom osnovnog obrazovanja operacionalizirat će se s obzirom na uspješnost socijalizacije učenika s teškoćama u njihovim inkluzivnim razrednim sredinama. U istraživanju je sudjelovalo ukupno 1087 učenika predmetne nastave 6., 7. i 8. razreda redovne osnovne škole. Metodologija se temelji na primjeni upitnika za operacionalizaciju socijalnih kompetencija učenika tipičnog razvoja ispitivanjem empatije i prosocijalnosti, a u području općeg razvoja samopoimanja i psihološke autonomije. Dodatna mjera za usporedbu uspješnosti inkluzije postignuta je primjenom sociometrijskog postupka. Postavljene su hipoteze 1) da provođenje inkluzivnog obrazovanja ima pozitivno značenje za uspješnost socijalizacije učenika s teškoćama; 2) da iskustvo inkluzije kod učenika tipičnoga razvoja ima pozitivno značenje za razvoj socijalnih kompetencija i razvojnih postignuća te 3) da uspješnost razvoja ovih postignuća ima pozitivno značenje za uspješno sklapanje prijateljstava s vršnjacima s teškoćama. Rezultati pokazuju da učenici s teškoćama u svojim razredima dominantno pripadaju skupini najslabije socijaliziranih učenika (zvijezde odbijanja) te njihova socijalizacija nije uspješna. Iskustvo inkluzije za učenike tipičnoga razvoja nije imalo pozitivno značenje za razvoj socijalnih kompetencija, samopoimanja ni psihološke autonomije jer se ne razlikuju značajno od svojih vršnjaka koji nisu imali ovo iskustvo, dok rezultati ovladavanja procesima adolescencije pokazuju i negativno značenje iskustva inkluzije kod djevojčica tipičnoga razvoja, što je suprotno očekivanjima. Kod učenika tipičnoga razvoja rezultati pokazuju da su socijalne kompetencije ključni aspekt za stvaranje prijateljstava s vršnjacima s teškoćama, praćene smanjenim osjećajem nekompetentnosti, usamljenosti i negacije potreba, temeljni su aspekti koji imaju pozitivno značenje za uspješnu socijalizaciju u inkluzivnoj sredini. Temeljem dobivenih rezultata izrađen je prijedlog modela pripreme učenika tipičnoga razvoja kako bi mogli uspješno svladati izazove koji u njihov rani adolescentni razvoj donose vršnjaci s teškoćama u inkluzivnim razredima, kako bi mogli s njima sklapati prijateljske odnose i time učiniti model odgojno-obrazovne inkluzije značajno uspješnijim.The inclusion of students with disabilities in regular primary schools with the development of individualized curricula presents many opportunities and challenges in an inclusive educational environment. Comparing different inclusion practices, it becomes apparent that some strategies yield positive results, while others fail due to a lack of preparation and support. Contrasting experiences of successful and unsuccessful inclusion highlight the need to research the significance of inclusion for students' developmental achievements. This dissertation aims to contribute to the success of implementing the model of educational inclusion with regard to the significance of the social and developmental achievements of typically developing students and, based on this, to develop a model of preparing typically developing students for successful mastery of inclusive tasks. The interest of this dissertation is to explore the significance of social competencies, self-concept and psychological autonomy of typically developing students for the successful implementation of the model of inclusive inclusion of students with disabilities (with individualized curricula) in regular subject classes and the significance of this experience for the developmental achievements of typically developing students. The main goal of the research is to establish, using a scientifically valid approach, the success of the development of social competences and self-concept of typically developing students, and the role and significance of the success of the development of these achievements of typically developing students in the implementation of inclusive tasks of building close and friendly relationships with peers with disabilities. The success of the inclusion model during primary education will be operationalized with regard to the success of the socialization of students with disabilities in their inclusive classroom environments. A total of 1087 students of subject teaching in the 6th, 7th and 8th grades of regular primary school participated in the research. The methodology is based on the application of a questionnaire for the operationalization of social competences of typically developing students by examining empathy and prosociality, and in the area of general development of self-concept and psychological autonomy. An additional measure for comparing the success of inclusion was achieved by applying the sociometric procedure. The hypotheses were 1) that the implementation of inclusive education has a positive meaning for the success of the socialization of students with disabilities; 2) that the experience of inclusion in typically developing students has a positive meaning for the development of social competences and developmental achievements, and 3) that the success of the development of these achievements has a positive meaning for the successful formation of friendships with peers with disabilities. The results show that students with disabilities in their classes predominantly belong to the group of the most poorly socialized students (rejection stars) and their socialization is not successful. The experience of inclusion for typically developing students did not have a positive meaning for the development of social competences, self-concept or psychological autonomy because they do not differ significantly from their peers who did not have this experience, while the results of mastering the processes of adolescence also show a negative meaning for the experience of inclusion in typically developing girls, which is contrary to expectations. In typically developing students, the results show that social competences are a key aspect for the formation of friendships with peers with disabilities, accompanied by a reduced sense of incompetence, loneliness and negation of needs, which are fundamental aspects that have a positive meaning for successful socialization in an inclusive environment. Based on the results obtained, a proposal was made for a model of preparing students with typical development so that they can successfully overcome the challenges that peers with difficulties bring to their early adolescent development in inclusive classes, so that they can form friendly relationships with them and thus make the model of educational inclusion significantly more successful
Immobilization of Burkholderia cepacia and Pseudomonas fluorescens lipases on eggshell membrane-based carriers
No full textLipaze su enzimi čija je primjena u odnosu na kemijske katalizatore vrlo poželjna posebno u imobiliziranom obliku. U današnje vrijeme postoje brojni nosači za imobilizaciju enzima na bazi otpada i/ili nusproizvoda poljoprivredno-prehrambene industrije, među kojima i membrane jaja. U okviru ovog doktorskog rada pripremljeni su nosači na bazi membrane jaja tretiranjem otpadne ljuske jaja s tri kiseline: 5 % klorovodičnom, 10 % octenom i 15 % o-fosfornom kiselinom. Na pripremljene nosače su primjenom tri tehnike imobilizacije (adsorpcija, kovalentno direktno i indirektno vezanje) imobilizirane lipaze iz bakterija Burkholderia cepacia i Pseudomonas fluorescens. Biokemijska i operativna svojstva imobiliziranih lipaza su pokazala pomak u pH i temperaturnom optimumu, bolju temperaturnu i skladišnu stabilnost u odnosu na slobodne lipaze te mogućnost korištenja u 10 uzastopnih ciklusa bez značajnog gubitka katalitičke aktivnosti. Na temelju dobivenih rezultata aktivnosti imobiliziranih lipaza, desorpcije te biokemijskih i operativnih svojstava odabrana je imobilizirana Burkholderia cepacia lipaza za provjeru funkcionalnosti u sintezi biodizela gdje ni 24 sata sinteze nije bilo dovoljno za sintezu udjela metilnih estera masnih kiselina propisanih pravilnikom. Provedena tehno-ekonomska analiza pripreme nosača na bazi membrane jaja i imobilizacije lipaza na iste pokazala je da ovaj pristup predstavlja ekonomski isplativu i održivu alternativu u odnosu na komercijalne nosače, kao i ekološki prihvatljivo rješenje smanjenja otpada njegovom transformacijom u vrijedne materijale.Lipases are enzymes whose use is highly desirable, especially in the immobilized form. Nowadays, there are numerous carriers for the enzyme immobilization based on waste and/or by-products of the agro-food industry, including eggshell membranes. In this thesis, eggshell membrane-based carriers were prepared by treating eggshells with three acids: 5% hydrochloric, 10% acetic and 15% o-phosphoric acid. Lipases from the bacteria Burkholderia cepacia and Pseudomonas fluorescens were immobilized on the prepared carriers using three immobilization techniques (adsorption, covalent direct and indirect binding). The biochemical and operational properties of the immobilized lipases showed a shift in pH and temperature optimum, better temperature and storage stability compared to free lipases and the reuse in 10 consecutive cycles without significant loss of catalytic activity. Based on the obtained results regarding the activity of immobilized lipases, desorption behavior, and biochemical and operational properties, immobilized Burkholderia cepacia lipase was selected for evaluation in biodiesel synthesis. However, even after 24 hours of reaction, the required fatty acid methyl ester (FAME) content specified by regulatory standards was not achieved.. The techno-economic analysis of the production of carriers based on eggshell membrane and the immobilization of lipases showed that this approach represents an economically viable and sustainable alternative to commercial carriers, as well as an environmentally friendly solution to reduce waste by converting them into valuable materials
THE ASSOCIATION OF INTERACTIONS BETWEEN PPARA AND PPARG GENE POLYMORPHISMS AND DIETARY HABITS WITH METABOLIC PARAMETERS AND SEVERITY OF SYMPTOMS IN PATIENTS WITH SCHIZOPHRENIA AND MAJOR DEPRESSIVE DISORDER
No full textCilj istraživanja: Proteini PPAR važni su u regulaciji metabolizma glukoze i lipida, upalnog
odgovora, oksidacijskog stresa i mnogim drugim biološkim procesima te su, stoga, značajni u
zdravlju, ali i etiopatogenezi niza bolesti uključujući psihičke bolesti poput shizofrenije i velikog
depresivnog poremećaja (VDP). Sustav gena/ proteina PPAR ovisi o ligandima iz prehrane, a, također,
polimorfizmi gena PPARA/ PPARG utječu na gensku ekspresiju te posljedično funkcije proteina
PPAR. Glavni cilj istraživanja bio je ispitati da li interakcije polimorfizama gena PPARA (L162V) te
PPARG (P12A i C161T) i prehrane utječu na metaboličke parametre (vrijednosti glukoze i lipida u
serumu) i težinu simptoma ovih bolesti. Slične studije na ovim kliničkim populacijama do sada nisu
objavljene. Ispitanici i metode: Skupina od 211 ispitanika oba spola - 94 bolesnika s dijagnozom
shizofrenije ili shizoafektivnog poremećaja te 117 osoba s VDP-om - uključena je u istraživanje u
periodu od 2014. do 2017., tijekom bolničkog liječenja pri Klinici za psihijatriju Kliničkog bolničkog
centra Rijeka. Istraživanje je uključilo prikupljanje demografskih i kliničkih/ medicinskih te podataka
o prehrambenim navikama bolesnika, kao i procjenu težine simptoma bolesti, a analizirani su
metabolički parametri te je provedena genotipizacija. Dobiveni podaci obrađeni su deskriptivnom
statistikom, neparametrijskim testovima, faktorskom analizom te općim linearnim modelom.
Rezultati: Istraživani polimorfizmi gena PPARA/ PPARG nisu čimbenici podložnosti za shizofreniju
niti VDP te (samostalno) ne utječu na metaboličke niti parametre težine simptoma bolesti. Potvrđene
su loše prehrambene navike u bolesnika obje skupine, a između skupina opažene značajne razlike u
obrascima unosa namirnica zdrave, nezdrave prehrane te mesa (prehrambeni faktori 1, 2 i 3). Nadalje,
prehrana utječe na promatrana obilježja - mediteranska prehrana modulira vrijednosti lipida u obje
skupine bolesnika, a učestalost unosa nezdrave prehrane (prehrambeni faktor 2) prediktor je težine
negativnih simptoma shizofrenije. Analiza interakcija polimorfizama gena PPARA/ PPARG i prehrane
pokazala je značajan utjecaj na obje vrste kliničkih obilježja - pritom, u skupini oboljelih od
shizofrenije interakcije imaju veći utjecaj na težinu simptoma bolesti, dok je u bolesnika s VDP-om
dokazan njihov veći utjecaj na metaboličke parametre. U interakciji s PPAR genotipom/ haplotipom,
konzumacija namirnica mediteranske te nezdrave prehrane (prehrambeni faktori 1 i 4 te 2) moduliraju
vrijednosti lipida, dok konzumacija namirnica nezdrave prehrane i mesa (prehrambeni faktori 2 i 3)
utječu na težinu simptoma obje bolesti. Zaključak: Istraživanjem je potvrđen utjecaj polimorfizama
gena (i proteina) PPAR i njihovih interakcija s prehranom na više kliničkih obilježja u shizofreniji i
VDP-u što upućuje da bi prehrambena intervencija, odnosno, modifikacija prehrambenih navika,
usklađena prema PPAR genotipu osobe, mogla rezultirati poboljšanjem metaboličkog zdravlja
oboljelih, kao i liječenja shizofrenije i VDP-a.Objectives: PPAR proteins are important in the regulation of glucose and lipid metabolism,
inflammatory response, oxidative stress and many other biological processes, and therefore, they are
significant in health, but also in the etiopathogenesis of many illnesses including mental illnesses such
as schizophrenia and major depressive disorder (MDD). PPAR gene/protein system depends on
ligands from the diet, and in addition, polymorphisms of the PPARA/ PPARG gene can change gene
expression and functions of PPAR proteins. Therefore, the main goal of the research was to examine
whether the interactions between polymorphisms of the gene PPARA (L162V) and gene PPARG
(P12A and C161T) and diet affect metabolic parameters (levels of glucose and lipids in serum) and
severity of symptoms. Similar studies on these clinical populations have not been conducted so far.
Patients and methods: The research included a total of 211 patients of both sexes: 94 patients with
schizophrenia or schizoaffective disorder and 117 persons with MDD. Patients were recruited between
2014 and 2017, during hospitalization at the Clinic for Psychiatry of the Clinical Hospital Center
Rijeka. The research included collecting demographic and clinical/ medical data, data on dietary
habits, and assessment of symptoms severity, as well as analysis of metabolic parameters and
genotyping. The obtained data were processed using descriptive statistics, nonparametric tests, factor
analysis, and general linear model. Results: Polymorphisms L162V in the PPARA gene, P12A and
C161T in the PPARG gene were not susceptibility factors for schizophrenia or MDD and,
independently, did not affect metabolic parameters or symptoms severity. All patients showed poor
eating habits, and significant differences between groups were observed in the patterns of intake of
healthy and unhealthy food as well as meat (dietary factors 1, 2, and 3). Furthermore, diet affected
clinical features: the Mediterranean diet modulated levels of lipids in both groups, while the frequency
of unhealthy food intake (dietary factor 2) was a predictor of severity of negative symptoms in
schizophrenia. The analysis of interactions between PPARA/ PPARG gene polymorphisms and diet
revealed a significant influence on both types of clinical features - in the schizophrenia group
interactions had greater influence on symptoms severity, and in MDD group greater influence was
found on metabolic parameters. In interaction with PPAR genotype/ haplotype, consumption of
foodstuff of Mediterranean and unhealthy diet (dietary factors 1, 4, and 2) modulated lipid parameters,
while unhealthy food and meat consumption patterns (dietary factors 2 and 3) influenced symptom
severity in two illnesses. Conclusion: Interactions between PPAR gene polymorphisms and diet
affected several clinical features in schizophrenia and MDD suggesting that nutritional intervention or
modification of eating habits, coordinated according to the person's PPAR genotype/ haplotype, could
result in an improvement of metabolic health as well as treatment of schizophrenia and MDD
Utjecaj crvenoga mulja na korozijska svojstva čelika u cementnim i alkalno aktiviranim mortovima : doktorski rad
No full textFour billion metric tons of cement are produced globally every year. Cement industry is one of the biggest worlds industries but also one of the biggest greenhouse gas emitters producing 8% of all greenhouse gases. It is estimated that by 2050, the cement industry will produce up to 24% of global CO2. At the present moment, a focus is on “greener” products like low-carbon cements to build and repair more efficient and sustainable buildings. One of the highest cost in maintenance and repair of reinforced structures is corrosion of reinforcing steel. To mitigate ecological footprint and high costs, there is an urgent need for novel materials that can meet these demands. Among other supplementary cementitious materials (SCM), waste product of an aluminium industry, called red mud, is getting increased attention. Red mud is obtained by processing the bauxite ore via Bayer’s procedure. Red mud is highly alkaline, clay-like material that poses great danger for the environment in the vicinity since it is stored in open and large landfill. Every year, tons of these product is pumped away for disposal which threats already existing landfills because it can overflow or cause cracks in dam walls. On the other hand, due to the favourable chemical composition, very fine particles and great availability, lately, red mud is being researched as a new potential SCM. This study explores the effects of red mud on the microstructure, compressive strength, chloride ion penetration resistance, and corrosion behaviour of steel reinforcement in cement-based and alkali-activated mortars. In the first phase of the dissertation, the research focused on the properties including chemical, mineralogical and radiological analysis of red mud, as well as of other materials used in present work, calcined clay, fly ash and blast furnace slag. It was found that red mud is crystalline and has lower reactivity compared to common SCMs, but it showed enhanced initial reactivity, high particle fineness and presence of alumina in chemical composition. Additionally, radiological analysis showed how red mud has an increased amount of naturally occurring radionuclides, however, when used in cement-based composites it was safe for human health. First phase of research also explored the reactivity of red mud in OPC when cement was partially replaced by red mud. Reactivity was assessed by making two sets of binders, one with red mud and other with inert quartz powder generally used as a filler material. Results showed how red mud was more reactive compared to quartz and influenced the cement hydration by forming new products, ultimately influencing compressive strength enhancement. Additionally, synergy of red mud and usual SCMs in cement based materials was explored. It was found that the
contribution of red mud on cement hydration was pronounced in the presence of alumina rich materials such as fly ash and clay.
In the second phase, the research focused on the influence of red mud on corrosion properties of steel embedded in cementitious and alkali-activated mortars. To understand corrosion behaviour of steel in composites with red mud, the influence of red mud on the microstructure of cement based and alkali-activated mortars was analysed. In addition to microstructural analysis, impact of red mud on resistance to chloride transport was assessed. Finally, to reveal the impact of red mud on corrosion performance, passive film was investigated of steels immersed in AAM pore solution with the presence of chlorides. It was also found that the red mud enhanced resistivity to chloride transport of OPC mortars in well optimized binders. Moreover, red mud contributed to better corrosion performance of OPC binders. In slag-based alkali-activated materials, red mud contributed to better pore refinement and hindered chloride transport. On the other hand, in fly ash based AAMs red mud affected microstructure by enhancing porosity and decreasing chloride binding of mortars. However, in both types of binders red mud enhanced protectivity of steel to chloride induced corrosion by stabilizing passive film.Svake se godine u svijetu proizvede četiri milijarde metričkih tona cementa. Cementna industrija jedna je od najvećih svjetskih industrija, ali i jedan od najvećih emitera stakleničkih plinova koja proizvodi 8% svih svjetskih stakleničkih plinova. Procjenjuje se da će do 2050. cementna industrija proizvoditi i do 24% globalnog CO2. Trenutačno je fokus na "zelenijim" proizvodima poput cementa s niskom emisijom CO2 za izgradnju učinkovitijih i održivijih zgrada. Jedan od najvećih troškova održavanja i popravaka armirano betonskih konstrukcija je korozija armaturnog čelika. Kako bi se ublažio ekološki otisak i veliki troškovi, postoji hitna potreba za novim materijalima koji mogu zadovoljiti te zahtjeve. Kao novi mineralni dodatak, sve veću pozornost dobiva otpad aluminijske industrije koji se dobiva preradom boksitne rude Bayerovim postupkom i naziva se boksitni ostatak ili crveni mulj. Crveni mulj je visoko alkalni, glinasti materijal koji predstavlja veliku opasnost za okoliš u blizini jer se skladišti na otvorenom velikom odlagalištu. Svake godine se tone ovog proizvoda ispumpaju na odlagališta što prijeti već postojećim odlagalištima jer se može preliti ili izazvati pukotine u zidovima brana. S druge strane, zbog kemijskog sastava, vrlo sitnih čestica i velike dostupnosti, crveni mulj se u posljednje vrijeme istražuje kao novi potencijalni mineralni dodatak cementima. Cilj ovog istraživanja je ispitivanje utjecaja crvenog mulja na mikrostrukturu, tlačnu čvrstoću, otpornost na prodor kloridnih iona i korozijsko ponašanje čelične armature u cementnim i alkalno aktiviranim mortovima. U prvoj fazi disertacije istraživanje je bilo usmjereno na svojstva crvenog mulja i drugih korištenih mineralnih dodataka. Ispitivanja su uključivala kemijsku, mineralošku, radiološku analizu crvenog mulja i drugih materijala korištenih u ovom radu, kao što su kalcinirana glina, leteći pepeo i zgura iz visokih peći. Utvrđeno je da je crveni mulj kristalan i ima manju reaktivnost u usporedbi s uobičajenim mineralnim dodatcima, ali pokazuje poboljšanu početnu reaktivnost, visoku finoću čestica i prisutnost aluminijevog oksida u kemijskom sastavu te u sinergiji s drugim materijalima može prevladati njihove nedostatke. Dodatno, radiološka analiza pokazala je kako crveni mulj ima povećanu količinu prirodnih radionuklida, međutim, kada se koristi u kompozitima na bazi cementa, siguran je za ljudsko zdravlje. Prva faza istraživanja također je istraživala reaktivnost crvenog mulja u OPC-u kada je cement djelomično zamijenjen crvenim muljem. Reaktivnost je procijenjena izradom dva tipa veziva, jednog s crvenim muljem, a drugog s inertnim kvarcnim prahom koji se općenito koristi kao filer. Rezultati su pokazali kako je crveni mulj reaktivniji u usporedbi s kvarcom i utječe na hidrataciju cementa stvaranjem novih produkata hidratacije, što u konačnici utječe na povećanje tlačne čvrstoće. Dodatno, istražena je sinergija crvenog mulja i uobičajenih SCM-ova u materijalima na bazi cementa. Utvrđeno je kako je doprinos crvenog mulja na hidrataciju cementa najviše izražen u prisutnosti materijala koji sadrže aluminate kao što su leteći pepeo i glina. U drugoj fazi, istraživanja su bila usmjerena na utjecaj crvenog mulja na korozijska svojstva čelika ugrađenog u cementne i alkalno aktivirane mortove. Kako bi se objasnio utjecaj na korozijska svojstva, istražena je i mikrostruktura cementnih i alkalno aktiviranih mortova. Osim mikrostrukturne analize, procijenjen je i utjecaj crvenog mulja na otpornost transportu klorida. Kako bi se bolje razumio utjecaj crvenog mulja na korozijsko ponašanje čelika, ispitivana su svojstva pasivnog filma čelika ugrađenih u simuliranu pornu otopinu AAM-ova s prisutnošću klorida. Ispitivanjima je utvrđeno kako crveni mulj povećava otpornost na transport klorida OPC mortova u dobro optimiziranim vezivima. Štoviše, crveni mulj doprinosi boljoj korozijskoj učinkovitosti OPC veziva. U alkalno aktiviranim mortovima na bazi zgure, mulj doprinosi boljoj preraspodijeli pora i otežanom transportu klorida. S druge strane, u AAMovima na bazi letećeg pepela crveni mulj utječe na mikrostrukturu povećavajući poroznost i smanjujući sposobnost mortova da kemijski vežu kloride. Međutim, u alkalno aktiviranim vezivima crveni mulj povećava zaštitu čelika od korozije izazvane kloridima stabilizacijom pasivnog filma
Croatian national survey of causative agents of urosepsis and antimicrobial resistance profile in maternity wards, neonatal intensive care units and divisions for pediatric nephrology
No full textInfekcije mokraćnog sustava (IMS) jedan su od najčešćih uzroka infekcija u neonatalnoj dobi, posebno u nedonoščadi i onih niske rodne mase. Nepravilno liječena IMS može dovesti do dugoročnih komplikacija ožiljčenja bubrega, razvoja ponavljanih uroinfekcija (cistični cistitis, hipertenzije i renalnog zatajenja u odrasloj dobi. Uz sepsu, IMS najčešće su hospitalne infekcije u jedinicama intenzivnog liječenja novorođenčadi. Identifikacija uzročnika u hemokulturi ključna je za primjenu odabranog antibiotika za liječenje urosepse jer rana primjena odgovarajuće terapije smanjuje smrtnost, ali i mogućnost trajnog oštećenja organskih sustava. U Hrvatskoj nisu provedene nacionalne studije o prevalenciji IMS kao ishodištu novorođenačke sepse, njihovim uzročnicima kao ni otpornosti patogena na antibiotike. Cilj istraživanja bio je ispitati epidemiologiju i etiologiju novorođenačke urosepse, kao i rezistenciju bakterijskih uzročnika na antibiotike u Hrvatskoj. Istraživanje je retrospektivna multicentrična analiza svih zabilježenih slučajeva urosepse u novorođenčadi 2005. i 2015. godine u Hrvatskoj. Utvrđeno je ukupno 114 slučajeva IMS, 16 slučajeva urosepse s identifikacijom identičnog uzročnika u urinokulturi i hemokulturi. Procijenjena incidencija urosepse iznosi 0,33 na 1.000 živorođenih 2005. godine te 0,24 na 1.000 živorođenih 2015. godine. Rezultati upućuju na potrebu daljnjih istraživanja u svrhu ispitivanja razlika u prevalenciji patogena i njihovoj otpornosti na antibiotike.Urinary tract infections (UTIs) are among the most common infections in neonates, particularly in premature and low birth weight infants. If untreated properly, UTIs can lead to kidney scarring, recurrent UTI (cystitis cystica), hypertension, and renal failure in adulthood. Alongside sepsis, UTIs are the most prevalent infections in neonatal intensive care units. Identifying the causative pathogen in blood cultures is crucial for guiding antibiotic treatment for urosepsis, since early appropriate therapy can reduce mortality and prevent permanent organ damage. In Croatia, there are no national studies assessing UTI prevalence as a source of neonatal sepsis, neither causative agents were analysed, nor their antibiotic susceptibility. This study examined the epidemiology, etiology, and antibiotic resistance of neonatal urosepsis in Croatia. A retrospective multicenter analysis was conducted on all recorded cases of neonatal urosepsis in 2005 and 2015. Out of 114 UTIs identified, there were 16 cases of urosepsis with matching pathogens in urine and blood cultures. The incidence of urosepsis regardless of identification of pathogen in blood was 0.33 per 1,000 live births in 2005 and 0.24 per 1,000 in 2015, accompanied with low
antibiotic resistance rates. Results indicate a need for further research to explore differences in pathogen prevalence and their resistance to antibiotics
Predictors of frequency of parental engagement in direct forms of child education
No full textRoditeljska uključenost u obrazovanje djeteta ključan je čimbenik koji doprinosi akademskom uspjehu, emocionalnom razvoju i dugoročnim životnim ishodima djece. Aktivno sudjelovanje roditelja u školskim aktivnostima i obrazovnom procesu povezuje se s razvojem snažnijih socijalnih i kognitivnih vještina, pozitivnim stavovima prema obrazovanju i većom samostalnošću djece. Svrha ovoga rada bila je doprinijeti razumijevanju roditeljske uključenosti u obrazovanje djeteta s naglaskom na akademski poticajne aktivnosti u obiteljskom okruženju. Cilj istraživanja bio je ispitati koji prediktori roditeljske uključenosti objašnjavaju učestalost roditeljskog uključivanja u obrazovanje djece u četiri izravna oblika: a) pomoć roditelja djeci u savladavanju školskih obveza, b) razgovor o školskim obvezama, c) razgovor o planovima u vezi daljnjeg obrazovanja i d) pružanje emocionalne podrške.
Korištena su tri skupa prediktora roditeljske uključenosti: individualne karakteristike roditelja i djece, obilježja obitelj i roditeljska odluka o uključenosti. Pritom, roditeljska se odluka odnosi na zajednički naziv za šest prediktora: a) shvaćanje roditeljske uloge, b) procjena samoefikasnosti roditelja za uključivanje u obrazovanje djeteta, c) stavovi roditelja o obrazovanju općenito, d) roditeljske aspiracije prema obrazovanju djeteta, e) roditeljska percepcija poziva učitelja za uključivanje u obrazovanje djeteta, f) roditeljska percepcija poziva za uključivanje u obrazovanje od strane djeteta. Podaci prikupljeni na uzorku roditelja djece osnovnoškolskog uzrasta (N=1461) obrađeni su metodama univarijatne, bivarijatne te multivarijatne statistike (hijerarhijska regresijska analiza i faktorska analiza). Percepcija roditeljske uloge, osjećaj samoefikasnosti i obrazovne aspiracije roditelja imaju pozitivan utjecaj na učestalost roditeljske uključenosti. Nadalje, inicijative učitelja i zahtjevi djece za podrškom dodatno potiču roditeljsku uključenost. Roditelji s većim osjećajem samoefikasnosti i visokim obrazovnim aspiracijama, uz podršku školske zajednice, češće se uključuju u obrazovne aktivnosti svoje djece. Na temelju dobivenih rezultata, mogu se kreirati smjernice za razvoj programa podrške roditeljima, prilagođene specifičnostima sredine, koje bi odgojno-obrazovne ustanove mogle samostalno prilagoditi. Time se doprinosi teorijskom znanju o roditeljskoj uključenosti i potiče primjena rezultata u razvoju programa i politika za aktivno uključivanje roditelja u obrazovni proces.Parental involvement in their child's education is a key factor in their academic success, emotional development and long-term life prospects. Active parental involvement in school activities and the educational process is linked to the development of stronger social and cognitive skills, a positive attitude towards education and greater independence in children.The aim of this study was to improve the understanding of parental involvement in a child's education, focusing on academically stimulating activities in the family environment. The aim was to investigate which predictors of parental involvement explain the frequency of parental involvement in four direct forms of educational support: a) Supporting children in schoolrelated tasks, b) Discussing school-related tasks, c) talking about plans for further education, and d) providing emotional support. Three groups of predictors of parental involvement were used: individual characteristics of parents and children, family characteristics, and parental decision-making regarding involvement. Parental decision making includes six predictors: a) understanding of the parental role, b) parents' self-efficacy to engage in their child's education, c) parents' attitudes towards education in general, d) parental hopes for their child's education, e) parents' perceptions of teachers' requests to be involved in their child's education, and f) parents' perceptions of their child's desire to participate. The data collected from a sample of parents of primary school-aged children (N=1461) were analyzed using univariate, bivariate and multivariate statistical methods (hierarchical regression analysis and factor analysis). The parents' understanding of their role, the feeling of self-efficacy and educational aspirations have a positive influence on the frequency of parental involvement. In addition, teacher initiatives and children's requests for support promote parental involvement. Parents with a stronger sense of self-efficacy and higher educational aspirations who are supported by the school community are more likely to be involved in their children's educational activities. Based on the results, guidelines can be developed for the design of support programs that are tailored to the specific needs of different communities and can be adapted independently by educational institutions. This contributes to the theoretical knowledge of parental involvement and encourages the application of the results in the
development of programs and strategies that actively promote parental involvement in the educational process