Repository of Josip Juraj Strossmayer University of Osijek
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ARBORETUMS OF CROATIA
Arboretum predstavlja ţivu zbirku razliĉitog drveća i grmlja koji ima
obrazovnu, uzgojnu i dekorativnu svrhu. Osnovna namjena arboretuma je uzgajanje autohtonih i alohtonih
vrsta drveća kako bi se prikupio i razmijenio razliĉit biljni materijal i time oĉuvala biološka raznolikost
pojedinog podruĉja. U Hrvatskoj postoje tri arboretuma, a dva su od njih nastala na podruĉju plemićkog
dvora i ljetnikovca. Uz arboretum Trsteno, koji je ujedno i najstariji arboretum na svijetu, u Hrvatskoj se
nalaze arboretumi Opeka i Lisiĉine. Uz autohtone vrste, razliĉite egzotiĉne vrste unesene u arboretum
povećavaju bioraznolikost i obogaćuju hortikulturu arboretuma. Unatoĉ tome, pojedina podruĉja arboretuma
su zapuštena ĉime se narušava mogući razvitak arboretuma.Arboretum represents a living collection of different trees and shrubs that has educational,
breeding and decorative purpose. The basic purpose of the arboretum is to cultivate native and alohton tree
species in order to gather and exchange different plant material to preserve the biodiversity of individual
areas. There are three arboretums in Croatia, and two of them were made in the area of the noble court and
the summer palace. Along with the Arboretum Trsteno, which is also the oldest arboretum in the world, there
are Arboretum of Opeka and Lisinĉina in Croatia. With autochthonous species, various exotic species
introduced into the arboretum increase the biodiversity and enrichment of the arboretum horticulture.
Nonetheless, some arboretum areas are neglected, which disturbs the possible development of arboretum
Web application for logging contacts for self-isolation purposes
Glavni cilj ovog rada bio je napraviti web aplikaciju koja omogućuje jednostavan pregled popisa zaraženih kontakata prijavljenog korisnika i prikazom nedavnih kontakata pojedinih osoba. Aplikacija omogućuje bilo kojoj osobi s odgovarajućim pristupnim podacima da se prijavi i dobije uvid i cijeli popis koji se nalazi u bazi podataka koja se nalazi na udaljenom poslužitelju. Svi korisnici imaju mogućnost dodavanja osoba na popis te pretraživanje popisa po određenim kriterijima. Uz to, korisnici s većim privilegijama imaju mogućnost mijenjanja podataka osoba na popisu, u slučaju da postoje krivo unešeni podaci, te brisanje pojedinaca s popisa. Web aplikacija je dostupna u svakom trenutku svakoj osobi dokle god je poslužitelj spojen s Internetom. Teorijski dio sadrži opis načina izrade stranice pomoću korištenja Bootstrap-a i Javascript-a i način uspostavljanja Apache poslužitelja i spajanje na bazu podataka pomoću PHP-a.The main goal of this undergraduate paper was to create a web application that enables a simple view of the list of infected contacts of logged in user with a display of recent contacts of individuals. The application allows anyone with the valid access credentials to log in and see the entire list contained in a database located on a remote server. All users have the option of adding people to the list and searching the list according to certain criteria. In addition, users with higher privileges have the possibility to change the data of people on the list, in case there is false data, and to delete individuals from the list. The web application is available at any time to anyone as long as the server is connected to the Internet. The theoretical part contains a description of how Bootstrap and Javascript are used and how to establish an Apache server and connect to a database using PHP
EVOLUTION OF THE PASSERINE BIRDS
Vrapčarice (Passerine) je red ptica najbrojniji vrstama. Dijeli se na dva podreda - Oscine (Pjevice) i
Suboscine (Ne-pjevice). Vrapčarice su monofiletička skupina ptica. Prve pjevice su se pojavile na južnoj
Zemljinoj hemisferi u ranom tercijaru. Na sjevernoj hemisferi su pronađeni samo fosilni ostaci ne-pjevica
(Suboscina) tog geološkog razdoblja. Vokalno učenje je imalo veliku ulogu u evoluciji i specijaciji
vrapčarica. Bitnu ulogu u evoluciji vrsta ovog reda imale su različite morfološke prilagodbe u pogledu
veličine tijela jer su za razliku od drugih ptica one gradile manja gnijezda .Passerine is the most diverse order of Aves. It is divided in two suborders: Oscine and Suboscine. Passerine
is monophyletic order. The first passerine lived in the southern hemisphere in the early tertiary. In the
northern hemisphere, only the fossil remains of a non-passerine (Suboscine) were found in that geological
period. Vocal learning had a big role in the evolution and specification of Passerine. An important role in the
development of this order was also the morphology of the bodies that needed a small nest
GENOTOXIC BIOMARKERS – CHARACTERISTICS AND APPLICATION
Genotoksikologija objašnjava utjecaj kemijskih i fizikalnih faktora na genetski materijal
koji uzrokuju nasljedne promjene (mutacije) u strukturnom integritetu genoma (mutagenost).
Provedbom odgovarajućih in silico (računalnih), in vitro (na staničnim kulturama ili
bakterijama) ili in vivo (na živim organizmima) metoda dobivaju se podaci o genotoksičnom
karakteru testiranog kemijskog spoja. In silico tehnike istraživanja genotoksičnosti kemikalija
imaju primjenu u preliminarnim istraživanjima spojeva, dok se in vivo i in vitro metode koriste
u svrhu dobivanja realnih rezultata o toksičnom karakteru kemikalije. U skupinu in silico
tehnika pripadaju računalni softveri čije se predviđanje mutagenosti temelji na već provedenim
istraživanjima čiji su rezultati pohranjeni u bazama podataka. In vitro i in vivo metode koriste
različite metodologije koje omogućuju ispitivanje utjecaja kemijskih spojeva na DNA od kojih
su najčešće Amesov test, MLA, MN i SCGE test.Genetic toxicology evaluates the impact of chemical and physical agents on genetic
material which cause hereditary changes (mutations) in structural integrity of the genome
(mutagenicity). Use of suitable in silico (computational), in vitro (cell cultures or bacteria) or
in vivo (living organisms) assays gives data on the genotoxicity of tested chemical or physical
agent. In silico methods of investigation are used in preliminary investigations of the
mutagenicity of tested chemical, while in vivo and in vitro techniques give realistic results on
the genotoxic character of tested chemical. Group of in silico methods consists of softwares
whose prediction of mutagenicity is based on existing data bases. In vitro and in vivo methods
use various methodologies which allow testing of the chemicals impact on the DNA. The most
used in vivo and in vitro methods are Ames, MN, MLA and SCGE assay
The effect of selenium on the ascorbate-glutathione cycle genes expression in wheat (Triticum aestivum L.)
Selen je mikronutrijent esencijalan za ljude i životinje, dok kod biljaka u malim koncentracijama djeluje u
obrani protiv nepovoljnih ekoloških abiotičkih i biotičkih čimbenika. Pri većim koncentracijama selen može
imati prooksidacijsko djelovanje i uzrokovati pojavu oksidacijskog stresa u stanicama. Važnu ulogu u
smanjenju negativnih posljedica uzrokovanih oksidacijskim stresom ima askorbat-glutationski ciklusi te
enzimi monodehidroaskorbat-reduktaza (MDHAR) i dehidroaskorbat-reduktaza (DHAR) koji čine njegov
važan dio. U ovom istraživanju ispitivao se utjecaj tretmana različitih koncentracija i oblika selena (selenat i
selenit) na razinu ekspresije gena mdhar i dhar u korijenu i izdanku pšenice (Triticum aestivum L., cv.
Kraljica). Tretman selenom je značajno utjecao na ekspresiju gena mdhar i dhar pri čemu je razina ekspresije
ovisila o kemijskom obliku i koncentraciji primijenjenog selna te o samom biljnom organu. Kako bi se
detaljnije razjasnio mehanizam djelovanja selena na antioksidacijski odgovor u biljaka, potrebno je ispitati i
ostale komponente antioksidacijskog sustava.Selenium is a micronutrient essential for humans and animals, while in plants low concentrations of selenium
help in protection against adverse ecological abiotic and biotic factors. At higher concentrations, selenium can
have prooxidative activity and induce oxidative stress in cells. An important role in reducing the negative
effects caused by oxidative stress has ascorbate-glutathione cycle and enzymes monodehydroascorbate
reductase (MDHAR) and dehydroascorbate reductase (DHAR) that make its important part. In this study, the
effect of various concentrations of selenium (selenate and selenium) on the expression of mdhar and dhar
genes in the roots and shoots of wheat (Triticum aestivum L., cv. Kraljica) was studied. Treatment with
selenium had a significant effect on the expression of mdhar and dhar genes, where the level of expression
depended on the chemical form and concentration of the applied selenium and on the type of plant organ itself.
In order to further clarify the mechanism of selenium on the antioxidant response in plants, other components
of the antioxidant system need to be investigated
Expression of genes involved in lignin synthesis in the barley stem
Kao komponenta stanične stijenke lignin igra važnu ulogu u
pružanju mehaničke potpore i transporta vode u biljkama. Sinteza lignina uključuje nekoliko
putova. U ovom radu analizirali smo ekspresiju gena uključenih u sintezu lignina: fenilalanin
amonijak-liazu (PAL), 4-kumarat: koenzim A ligazu (4CL) i reduktazu cinamoil-koenzima A
(CCR) kao i celuloza sintetazu (CesA). Analize su provedene na tri kultivara ječma (Hordeum
vulgare L.) u fazi nalijevanja zrna koristeći lančanu reakciju polimeraze u realnom vremenu
(qPCR). Rezultati su pokazali da se ekspresija PAL, 4CL, CCR i CesA razlikuje u odnosu na
referentni gen (ADP-ribozilacijski faktor 1-sličan protein, ADP). Najveća ekspresija
zabilježena je u kultivaru Osvit, zatim slijedi kultivar Titan pa Predator koji je ujedno imao i
najnižu ekspresiju svih gena.As a part of the plant cell wall lignin plays an important roles providing
mechanical support and water transport. Lignin synthesis includes several pathways. We
analysed expression of genes involved in lignin synthesis: phenylalanine ammonia-lyase
(PAL), 4-coumarate: CoA ligase (4CL) and cinnamoyl-CoA reductase (CCR) as well as
cellulose synthase (CesA). Analyses were performed on three spring barley (Hordeum
vulgare L.) cultivars at grain filling stage by using real-time polymerase chain reaction
(qPCR). Results showed that expression of PAL, 4CL, CCR and CesA differed in comparison
to the reference gene (ADP-ribosylation factor 1-like protein, ADP). The highest expression
was observed in cultivar Osvit, followed by Titan and Predator which had the lowest
expression of all genes
Diversity and representation of diatoms in the phytoplankton of Lake Sakadaš (Nature Park Kopački rit)
Tijekom 2015. godine provedeno je istraživanje sezonskih sukcesija planktonskih dijatomeja u Sakadaškom
jezeru (Park prirode Kopački rit). Utvrđena je velika raznolikost dijatomeja (116 svojti), posebno u
ranoproljetnom i zimskom razdoblju u uvjetima nižih temperatura vode i smanjenog intenziteta svjetlosti koji
pogoduju njihovom razvoju. Analize su pokazale jak sezonski utjecaj i važnost hidroloških prilika u
oblikovanju sastava zajednica i brojnosti pojedinih vrsta dijatomeja. U jezeru su, uz primarno bentoske vrste
dijatomeja, najzastupljenije centrice (Aulacoseira granulata, Stephanodiscus hantzschii, Cyclotella
meneghiniana, Cyclostephanos dubius, Aulacoseira pusilla) zbog boljeg prilagođavanja promjenjivim
uvjetima u vodenom stupcu, posebice u vrijeme plavljenja. Uz sastav i zastupljenost vrsta, veliki sadržaj
hranjivih tvari u vodi, visoke koncentracije klorofila i niske vrijednosti prozirnosti, posebice u ljetnim
mjesecima, ukazuju na eutrofno stanje jezera.The seasonal succession of planktonic diatoms was studied in Lake Sakadaš (Nature Park Kopački rit) in 2015.
A large diversity of diatoms (116 taxa) has been identified, especially in the early spring and winter, under the
conditions of lower water temperatures and reduced light intensity that favour their development. The analyses
showed a strong seasonal influence and the importance of hydrological conditions in shaping the composition
of communities and the abundance of individual diatom species. A greater presence of centric species
(Aulacoseira granulata, Stephanodiscus hantzschii, Cyclotella meneghiniana, Cyclostephanos dubius,
Aulacoseira pusilla) was found, which, due to their morphological and functional characteristics, were better
adapted to changing conditions in the water column, especially during flooding. Also, a significant portion of
primarily benthic diatom species has been identified in lake phytoplankton. Besides species composition and
abundance, the high nutrient content and chlorophyll concentrations as well as low water transparency,
especially in summer, indicate the eutrophic state of the lake
Misconceptions and using conceptual maps as a way od evaluating
Utvrđivanje miskoncepcija i konceptualnog razumijevanja vezanih uz
fotosintezu i stanično disanje provedeno je među 49 učenika 3. razreda Opće gimnazije u Osijeku u školskoj godini
2018./2019. Učenici postižu slabe rezultate na pisanoj provjeri znanja te su na osnovi ukupnog uspjeha svakog
pojedinog učenika definirane klase uspješnosti. Jedan od mogućih načina uklanjana miskoncepcija upotreba je
konceptualne mape. Analizom pisane provjere znanja i konceptualne mape evidentirana je ista miskoncepcija
miješanja kloroplasta i klorofila. Rezultati konceptualne mape ne razlikuju se kod najboljih i najlošijih učenika te
su uočeni slični odgovori učenika što nam ukazuje na nedostatak prakse i iskustva u korištenju mapa prilikom
učenja ili procjenjivanja. Analizom ankete o navikama učenja može se zaključiti da većina učenika još uvijek
smatra da je profil nastavnika ključan za uspjeh u njihovom učenju te odbijaju preuzeti odgovornost za vlastito
učenje. Većina učenika za učenje koristi samo prezentacije s nastave, bez upotrebe alata za učenje, poput
konceptualne mape, koji bi potaknuli konceptualno razumijevanje i postizanje više kognitivne razine znanja.Determination of misconceptions and conceptual understanding related to photosynthesis and
cellular respiration was conducted among 49 3rd grade students of the General High School in Osijek in the
school year 2018/2019. Results show students’ poor understanding of the concepts which corresponds with the
written proficiency testing. Based on the overall success of each student, performance classes are defined. One
possible way to eliminate misconception is to use a concept map. The analysis of the students’ conceptual map
corresponds with their written knowledge assessment and reveals the same misconception of mixing chloroplasts
and chlorophylls. Furthermore, there is no difference between more and less successful students when it comes
to the results of the concept map. Similar student responses indicate a lack of practice and experience in using
the maps. The analysis of the survey on the learning habits shows that most students still consider the teacher as
a crucial role in their learning success. This indicates their lack of responsibility for autonomous learning. Most
students use only teacher presentations for learning, and they do not use teaching aids such as a concept map that
can improve their conceptual understanding and help them reach a higher cognitive level of knowledge
USE OF DEEP EUTECTIS SOLVENTS IN SYNTHESIS OD THIOSEMICARBAZIDES AND TRIAZOLES
„Zelena“ kemija obuhvaća niz ideja i aktivnosti temeljenih na 12 načela s ciljem uvođenja promjena u kemijske procese
radi što manjeg utjecaja na okoliš i živa bića u njemu. Uporabom blažih, tzv. „zelenih“ otapala nastoji se u što većoj mjeri
smanjiti korištenje opasnih organskih otapala. Eutektička otapala predstavljaju jednu od tih alternativa. Zbog svoje slabe
hlapljivosti, netoksičnosti, jednostavne priprave, niske cijene, biorazgradivosti te mogućnosti recikliranja, eutektička su se
otapala pokazala kao odličan medij za brojne reakcije. Cilj ovoga rada je ispitati primjenu eutektičkih otapala na bazi kolinklorida u sintezi tiosemikarbazida i triazola. Prema dobivenim rezultatima, eutektička otapala pokazala su se pogodnima u
sintezi željenih spojeva. Došlo je do sinteze čistih spojeva ili njihove smjese u različitim omjerima, ovisno o vrsti otapala.
Otapala su se pokazala ekološki i ekonomski isplativa u sintezi navedenih spojeva.Green chemistry encompasses a series of ideas and activities based on 12 principles, with the aim of introducing changes
to chemical processes to reduce the negative impact on the environment and living system. The use of milder, so called
green solvents seeks to minimize the use of hazardous organic solvents. Eutectic solvents represent one of these alternatives.
Due to their low volatility, non-toxicity, easy preparation, low cost, biodegradability and recyclability, eutectic solvents
have proven to be an excellent medium for many reactions. The aim of this paper is to explore the use of choline chloridebased deep eutectic solvents in the synthesis of thiosemicarbazides and triazoles. According to the obtained results, eutectic
solvents have proved to be suitable for the synthesis of the desired compounds. It resulted in the synthesis of pure
compounds or their mixtures in different proportions, depending on the type of solvent. Solvents have proven to be
environmentally and economically viable in the synthesis of the mentioned compounds
Animal parental care
Razvitak brige za mlade pruža mladima veću šansu za preživljavanje iako zahtjeva puno
energije i vremena. Postoji nekoliko tipova brige za mlade, svaki je specifičan i prilagođen
pojedinoj vrsti. Kod većine ptica prevladava monogamija jer oba roditelja mogu nahraniti
dvostruko više mladih nego jedan roditelj, i mužjak i ženka će povećati svoj reproduktivni
uspjeh tako što će zajedno brinuti za mlade. U sisavaca ženke su još više predodređene
brinuti za mlade, pa prevladava poliginija. Mladi često imaju produljeno razdoblje razvijanja
unutar ženke za koje vrijeme mužjaci mogu pripomoći u brizi za mlade.Evolution of parental care provides better chance of survival even though it requires a lot of
energy and time. There are several types of parental care each specific and adjusted to a
particular species. The most common type among most birds is monogamy because both
parents are able to feed twice as much as one parent so male and female will increase their
reproductive success by providing care togther. In mammals, females are more
predetermined to care for the youngs so most mammals are polygyny. The youngs often
have extended time developing inside mothers so in that time males can provide any help