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No full textThis Master’s Thesis describes the modern treatment of symmetries in quantum field theories which is the result of recent developments and a change in perspective on symmetries in which symmetries are given by topological operators of the theory. It outlines the basic notions of category theory used in the SymTFT construction as well as the basic aspects of Topological Quantum Field Theories (TQFTs) needed to tackle the subject without relying heavily on the string theory and Conformal Field Theory (CFT) machinery which is usually present in other papers on this subject. Lastly, it uses the Chern-Simons and BF theory to provide elementary examples of the SymTFT construction at work.Ovaj diplomski rad izlaže moderan tretman simetrija u kvantnim teorijama polja koji je rezultat nedavnih napredovanja u razumijevanju simetrija iz nove perspektive u kojoj su simetrije dane topološkim operatorima teorije. Rad izlaže osnovne pojmove teorije kategorije korištene u SymTFT konstrukciji kao i osnovne aspekte topoloških kvantnih teorija polja (TQFT) koji su potrebani za svladavanje ove teme bez oslanjanja na mašineriju teorije struna i konformalnih teorija polja (CFT) koja je prisutna u većini radova na ovu temu. Konačno, korišteni su primjeri Chern-Simonsove i BF teorije kako bi se demonstrirala SymTFT konstrukcija
Multiplicity-dependent production of Σ(1385)± and Ξ(1530)0 in pp collisions at √s=13 TeV
No full textThe production yields of the Σ(1385)± and Ξ(1530)0 resonances are measured in pp collisions at √ s = 13 TeV with ALICE. The measurements are performed as a function of the charged-particle multiplicity ⟨dNch/dη⟩, which is related to the energy density produced in the collision. The results include transverse momentum (pT) distributions, pT-integrated yields, mean transverse momenta of Σ(1385)± and Ξ(1530)0 , as well as ratios of the pTintegrated resonance yields relative to yields of other hadron species. The Σ(1385)±/π± and Ξ(1530)0/π± yield ratios are consistent with the trend of the enhancement of strangeness production from low to high multiplicity pp collisions, which was previously observed for strange and multi-strange baryons. The yield ratio between the measured resonances and the long-lived baryons with the same strangeness content exhibits a hint of a mild increasing trend at low multiplicity, despite too large uncertainties to exclude the fat behaviour. The results are compared with predictions from models such as EPOS-LHC and PYTHIA 8 with Rope shoving. The latter provides the best description of the multiplicity dependence of the Σ(1385)± and Ξ(1530)0 production in pp collisions at √ s = 13 TeV
Composition and provenance of sandstone cobbles from the upper alluvial unit of the Promina Beds (surroundings of Obrovac, northern Dalmatia)
No full textPodručje vanjskih Dinarida u okolici Obrovca prema Benkovcu pretežito je prekriveno aluvijalnim i marinskim sedimentnim stijenama gornjoeocenske i oligocenske starosti. Uslijed taložnih i tektonskih promjena unutar akumulacijskih zona formira se najmlađa jedinica Prominskih naslaga trošenjem materijala s obližnjeg mladog orogena u obliku molasnih naslaga. Usporednom analizom uzorkovanih oblutaka pješčenjaka iz konglomeratne jedinice gornjoeocenske do donjooligocenske starosti i laporovitih pješčenjaka fliške jedinice srednjoeocenske starosti pretpostavljaju se međusobni odnosi i zajedničke karakteristike na temelju mikrofosilnih nalaza i sadržaja teških minerala. Dok analizirani fliški pješčenjaci sadrže bogatije nalaze bentičkih foraminifera, oblutci pješčenjaka imaju bogatije nalaze planktonskih foraminifera te veći udio karbonatne komponente. Teški minerali također pokazuju znatne razlike s oscilacijama omjera grupa granata i tinjaca, ali i drugih minerala kao što su apatit, kijanit, jarosit i titanit. Pretpostavljeno je porijeklo oblutaka u stijenama unutarnjih Dinarida, čije su izvorne naslage vjerojatno bile starije od uzorkovanog eocenskog fliša.The area of the Outer Dinarides in the surroundings of Obrovac and Benkovac is predominantly covered by alluvial and marine sedimentary rocks of late Eocene and Oligocene age. Due to tectonic changes, the youngest unit of the Promina Beds was deposited as molasse, formed by erosion of the nearby young orogen. The study compares the microfossil and heavy mineral content of sandstone cobbles found in the upper Eocene to lower Oligocene alluvial conglomerates and marly sandstones of the middle Eocene flysch unit. The flysch samples show numerous skeletal remains of benthic foraminifera, whereas sandstone cobbles show more planktonic foraminifera, as well as a higher CaCO3 content. Heavy minerals such as garnet, apatite, kyanite, jarosite, titanite and mica vary in abundance among the samples. It is suggested that the sandstone cobbles originate from rocks found in the Inner Dinarides, which were most likely older than the sampled Eocene flysch
Tenzorske algebre i primjene
No full textGlavni cilj ovog rada bio je prikazati osnovnu teorijsku pozadinu tenzorske algebe. Uz opisan tenzorski produkt i osnovne objekte algebre, konstruirana je tenzorska algebra i dokazano je njeno univerzalno svojstvo, točnije da dijagram komutira. Konstruirana je i kvocijentna algebra , poznata kao i simetrična algebra. Za kraj je dan kratak pregled primjene tenzora u ekonomiji kroz Bayesov autoregresivni tenzorski model.The main goal of this thesis was to present the fundamental theoretical background of tensor algebra. Alongside a description of the tensor product and basic algebraic objects, the tensor algebra is constructed, and its universal property is proven, specifically that the diagram commutes.
Additionally, the quotient algebra , also known as the symmetric algebra, is constructed. Finally, a short overview of tensor applications in economy is provided, with a focus on the Bayesian autoregressive tensor model
Floristic Characteristics of the Island of Krk
No full textOtok Krk najsjeverniji je otok Hrvatske i smješten je u Kvarnerskom zaljevu. S obzirom na prirodno-geografska obilježja može se podijeliti na tri dijela, sjeverni, središnji i južni. Svaki od njih ima karakterističan reljef i staništa koja su bogata biljnim vrstama od kojih su neke ugrožene i endemične. Otok također ima zaštićena područja i područja ekološke mreže koja su važna za očuvanje stanišnih tipova i njima pripadnih vrsta.The Island of Krk is the Croatian northernmost island located in the Bay of Kvarner. According to its natural geographic characteristics it can be divided into three parts, Northern, Middle and Southern. Each part has its specific landscape and habitats with many plant species, common, endemic and endangered. Protected landscapes and areas which are a part of protected areas network can be found on the island as they are important for protection of threatened species and their habitats
MOLECULAR CHARACTERIZATION OF EPSTEIN-BARR VIRUS IN MALIGNANT TUMORS
No full textVirus Epstein-Barr je ljudski gamaherpesvirus tip 4. Infekcija virusom EBV može uzrokovati
infektivnu mononukleozu, a povezuje se i s multiplom sklerozom i malignim bolestima. Na
temelju polimorfizama gena EBNA-2 i EBNA-3 EBV se klasificira u dva genotipa, a na temelju
polimorfizama gena BNLF-1 i EBNA-1 na različite podtipove. S obzirom da istraživanja
varijacija genoma EBV i filogenetska analiza mogu pridonijeti razumijevanju patogeneze
bolesti i razvoju terapijskih mehanizama, cilj ovoga istraživanja bio je odrediti podtipove virusa
EBV u malignim tumorima različitog porijekla i razvojnog stupnja. Iz uzoraka tumorskog tkiva
pacijenata oboljelih od Hodgkinovog limfoma, angioimunoblastičnog T-staničnog limfoma i
karcinoma nazofarinksa izolirana je DNA. Umnoženi su i sekvencirani specifični fragmenti
gena BNLF-1, EBNA-1, EBNA-3C i EBER. Analiza sekvencija EBNA-3C pokazala je da su svi
analizirani uzorci malignih tumora inficirani genotipom EBV-1, a sekvencije gena BNLF-1,
EBNA-1 i EBER da u istraživanim tumorima postoje različiti podtipovi virusa EBV. U
Hodgkinovom limfomu prevladava podtip B95-8, a u karcinomu nazofarinksa North Carolina
i P-ala. Novopredloženi podtip EBER Hrv2 češće je prisutan Hodgkinovom limfomu i
angioimunoblastičnom T-staničnom limfomu nego u karcinomu nazofarinksa.Epstein-Barr virus is human gamma herpesvirus type 4. EBV can cause infectious
mononucleosis and has also been linked to development of multiple sclerosis and malignant
tumours. Based on the EBNA-2 and EBNA-3 polymorphisms, EBV is classified into two
genotypes. Further subclassification is most often based on BNLF-1 and EBNA-1 variations.
Because EBV genome variations and phylogenetic analysis can contribute to the understanding
of the disease pathogenesis and the development of therapeutic mechanisms, the aim of this
study was to determine EBV subtypes in malignant tumors of different origin and stage of
development. DNA was isolated from tumor tissue samples of patients diagnosed with
Hodgkin's lymphoma, angioimmunoblastic T-cell lymphoma and nasopharyngeal carcinoma.
Specific fragments of the BNLF-1, EBNA-1, EBNA-3C and EBER genes were amplified and
sequenced. Analysis of EBNA-3C sequences showed that all tumor samples are infected with
genotype EBV-1, while BNLF-1, EBNA-1 and EBER sequences showed that tumor tissues are
infected with different EBV subtypes. B95-8 subtype predominates in Hodgkin's lymphoma,
while in nasopharyngeal carcinoma most frequent subtypes are North Carolina and P-ala. The
newly proposed EBER subtype Hrv2 is more frequently present in Hodgkin's lymphoma and
angioimmunoblastic T-cell lymphoma than in nasopharyngeal carcinoma
Activities on small Solar System bodies and modern methods of determining their physical characteristics
No full textU Sunčevom sustavu, osim Sunca i planeta, do danas je otkriveno gotovo milijun malih tijela Sunčevog sustava. Zbog njihovih malih dimenzija, oni spadaju u objekte čije istraživanje često zahtijeva teleskope velikih promjera ili primjenu suvremenih opažačkih metoda. Jedna od suvremenih opažačkih metoda određivanja fizikalnih karakteristika malih tijela Sunčevog sustava, koja dozvoljava razlučivosti veće od bilo koje druge zemaljske metode, jest metoda zvjezdanih okultacija. Mala tijela po sastavu i orbitalnim parametrima možemo klasificirati u asteroide i komete. Međutim, među asteroidima se pojavljuje malobrojna skupina objekata koji pokazuju aktivnosti slične kometskim. U doktorskom radu istražena je mikroaktivnost malog tijela 95P/(2060) Chiron. Zbog nedavne indikacije da bi Chiron mogao posjedovati prstenove, njegov mehanizam gubitka mase može biti objašnjen udarima krhotina iz Chironove orbite koje padaju na njegovu površinu. Opažanja su prikupljana na Španjolskoj zvjezdarnici Calar Alto, a za analizu su uglavnom korištene fotometrijske metode. Određivanjem Chironove rotacijske krivulje sjaja i njegove apsolutne zvjezdane veličine, potvrđena je pretpostavka da Chiron posjeduje prstenove. Kao primjer primjene metode zvjezdanih okultacija u svrhu istraživanja fizičkih karakteristika malih tijela Sunčevog sustava, opisano je određivanje veličine, oblika, albeda i gustoće patuljastog planeta Haumea, gornje granice Haumeine atmosfere, te otkriće i karakterizacija prstenova oko glavnog tijela Haumee. U svrhu poboljšanja vremenske razlučivosti opažanja zvjezdanih okultacija s malim tijelima, istražena je i opisana mogućnost primjene atmosferskih Čerenkovljevih teleskopa MAGIC. Njihovi veliki promjeri i osjetljivi fotomultiplikatorski detektori s visokim frekvencijama uzorkovanja, osim za unapređenje razlučivosti u određivanju fizičkih karakteristika malih tijela Sunčevog sustava, mogu biti korišteni za izravna mjerenja promjera zvijezda. U doktorskom radu opisana je metoda određivanja zvjezdanih promjera pomoću detekcije Fresnelovih difrakcijskih uzoraka, koji se mogu opaziti tijekom zvjezdanih okultacija. Detaljno je modeliran signal kakav bi bio opažen teleskopima MAGIC, uzevši u obzir karakteristike teleskopa i osjetljivost detektora. Kroz opažačke prijedloge ostvareno je teleskopsko vrijeme za opažanje zvjezdanih okultacija s MAGIC teleskopima.Extended abstract - Besides the Sun and the planets, our Solar System contains nearly 1 million discovered small Solar System bodies. Due to their small size, they belong to objects whose research often requires large-sized telescopes or the application of modern observation methods. One of today’s modern observational methods used for determining the physical characteristics of the small Solar System bodies, allowing several orders of magnitude better resolutions than any other Earth-based method, is the stellar occultations method. By composition and orbital parameters, small Solar System bodies can be classified into asteroids and comets. Nevertheless, there is a group of asteroid-like objects that show cometlike activities. This doctoral thesis consists of 3 parts. In part one, the observed micro activity of the small Solar System body 95P/(2060) Chiron was investigated. In part two, as an extensive example of the application of the stellar occultation method to investigate the physical characteristics of small Solar System bodies, the determination of the dwarf planet’s Haumea size, shape, albedo, and density was described. In part three, in order to improve the temporal resolution of observations of stellar occultations with small bodies, the potential of using the atmospheric Cherenkov telescopes MAGIC for observing stellar occultations was investigated. Activity of 95P/(2060) Chiron The minor planet 95P/(2060) Chiron belongs to the asteroid group of centaurs, which according to dynamic parameters belongs to asteroids. Chiron has an orbit far away from the Sun, in which sublimation of water ice is not considered as a possible cause for triggering mass loss mechanisms. The expected rate of collisions among small bodies in the region of centaurs is not expected to be high. Regardless of that, since its discovery, Chiron has repeatedly shown indications of cometary activity (Kowal et al. 1979; Tholen et al. 1988; Meech Belton 1990). In 2015, Ortiz et al. (2015) found indications that (2060) Chiron possesses rings. Motivated by these findings, additional observations and interpretations of the cause of its activity were made and described in this doctoral thesis (and published in Cikota et al., 2018). Observations were carried out in three different observation campaigns between 2014 and 2016, using three different instruments located at the Calar Alto Observatory (CAHA) in Almeria, Spain - 3.5 m MOSCA, 1.23 m DLR-MKIII and 2.2 m CAFOS. From the collected observations, amplitudes of Chiron’s rotational light curves and measurements of Chiron’s absolute magnitudes were determined. The measured amplitudes are consistent with the model proposed by Ortiz et al. (2015) which is taking into account both, Chiron’s triangular ellipsoid-like shape and the light contribution of rings around Chiron. Although the frequency of collisions among small bodies in the centaur region is very low, iv due to the recent indication that Chiron possesses rings, and assuming that there is debris orbiting around Chiron, it is well possible that some of this debris may be continually falling and impacting on its surface, producing outbursts and forming a bound or quasi-bound coma. Consequently, a dust release mechanism triggered by impacts should not be excluded as a possible cause for its activity. To study this hypothesis, the scatter in Chiron’s photometric data was compared to the scatter of comparison stars of similar brightness as Chiron. The scatter of Chiron’s photometric measurements for the observations carried out on July 23 and 24, 2014, with the DLR-MKIII 1.23 m CAHA telescope was found to be 0.027 mag, while the comparison star’s scatter is 0.014 mag. During the photometric campaign in 2015, containing data collected with CAFOS 2.2 m CAHA telescope on September 11 and September 13, the scatter of Chiron’s photometric measurements was determined to be 0.029 mag, while the comparison star’s scatter values were 0.018 mag. The noticeable difference between the comparison star’s and Chiron’s photometric scatter supports our hypothesis of continuous micro activity on Chiron. That mechanism could also be a plausible explanation for impulsive brightening on a timescale of hours that have been observed by Luu Jewitt (1990). We hypothesize that some activity outbursts on regular comets could also be triggered by collisions, either with debris orbiting them or with meteoroids. Additionally, the data collected with the CAFOS 2.2 m CAHA telescope over 3 nights between September 11 and September 14, 2015, was used to search for comet-like activity signs like coma or tail. The data was combined to a false-color image of Chiron that contains 95 integrations of 300 s each, resulting in a total integration time of 28500 s (475 min). The combined image of Chiron shows that the coma itself is not detectable, but a very faint asymmetric shape with a measured position angle of ∼ 87◦ was observed. The feature can be explained by a ∼5 arcsec long comet-like tail, of a determined surface brightness of 25.3 mag(R)/arcsec2. Determination of the dwarf planet Haumea’s physical characteristics - Five dwarf planets are currently known in our Solar system. (1) Ceres is the closest dwarf planet to us, and the only dwarf planet orbiting in the inner part of the Solar system, within the main belt of asteroids. Four dwarf planets - (134340) Pluto, (136199) Eris, (136108) Haumea, and (136472) Makemake, are members of the Kuiper belt, located in the outer part of the Solar system beyond Neptune’s orbit. Due to the large distances of dwarf planets in the outer Solar system, indirect observation methods are necessary to accurately determine their physical characteristics. Among trans-Neptunian objects, the dwarf planet Haumea stands out in its elongated shape and extremely short rotation period (Brown et al. 2005; Rabinowitz et al. 2006; Brown et al. 2007). Unlike other dwarf planets (Sicardy et al. 2011; Ortiz et al. 2012; Stern et al. v 2015), Haumea’s physical characteristics were not precisely determined. In this doctoral thesis, the determination of Haumea’s size, shape, albedo, and density was described, as well as the discovery and characterization of its rings (published in Ortiz et al. 2017). On January 21, 2017, a stellar occultation of the dwarf planet Haumea was observed. The occulted star URAT1 533-182543 with its apparent brightness of = 17.6 mag made it observable already for small- and mid-sized telescopes. Therefore, the occultation event was observed from many locations and resulted in 12 positive detections from 10 different sites across Europe. From the collected sequences of CCD images, photometric measurements of the synthetic aperture were performed. In the case of data collected from the Črni Vrh Observatory by the drift method, a special procedure of photometric analysis was applied to the stellar trail. By fitting a square well model to the collected photometric measurements, the times of the star’s disappearance and reappearance were determined, and occultation chords were generated for each observation location. To the chords in the projected plane, an elliptical limb was fitted by minimizing a 2 function. By that, the apparent edge of the shape of the ellipse, which represents the outline of Haumea’s shadow, was determined. The determined parameters of the major and minor axis of the ellipse are 1 704 ± 4 km and 1 138 ± 26 km respectively. The position angle of the minor axis is -76.3◦ ± 1.2◦. A search for an atmosphere was performed and the upper value of Haumea’s atmospheric pressure was determined by using the best available data set collected by the Asiago Observatory. From Haumea’s mass, and assuming that the body is in hydrostatic equilibrium, an average surface gravity of 0.39 ms−2 was determined. By comparing a modelled occultation light curve with the observed light curve, the upper value of Haumea’s pure isothermal global atmosphere of 2 in thermal equilibrium can be determined. Assuming a surface temperature of 40 K, we find a 1 upper limit for surface(2) = 3 nbar, and a 3 upper limit for surface(2) = 15 nbar. In addition to the main occultation, there are brief dimmings prior to and after the main event. These dips are consistently explained by a narrow and dense ring around Haumea that absorbed about 50% of the incoming stellar flux. A distinct cross-sectional profile of the rings collected in an observation with the 1 m telescope of the Konkoly Observatory reveals a radial ring width of ring ≈ 74 km at the occultation ingress and ring ≈ 44 km at the occultation egress, with corresponding apparent transparency of p’ = 0.55 and p’ = 0.56. The locations of twelve detected secondary events, projected in the sky plane, allow the retrieval of the full ring orbit, assuming an apparent elliptical shape, and using the same approach as used for fitting Haumea’s limb. The parameters of the elliptical fit to the rings are 0 ring = 2287+75 −45 km for the apparent semimajor axis, and 0 ring = 541 ± 23 km for a semiminor axis. The position angle of the minor vi axis is ring = -74.3◦ ± 1.3◦. Assuming the rings are circular, it implies a radius of the ring of ring = 2287+75 −45 km and an inclination angle of ring = 13,8◦ ± 0.5◦. The circular ring assumption is supported by the fact that the center of the ring ellipse coincides with the order of uncertainty with the center of the limb of Haumea’s main body. The position angle of the ring minor axis ring = -74.3◦ ±1.3◦ coincides with that of the limb minor axis limb = -76.3◦ ± 1.2◦, which is another strong argument that we are observing a ring that settled into Haumea’s equatorial plane. Furthermore, it was found that the radius of the rings coincides with the area where 3:1 spin-orbit resonances are expected. From the determined parameters of Haumea’s limb, a three-dimensional shape and density of Haumea were determined. The obtained parameters of the triaxial ellipsoid a × b × c are (1 161 ± 30) km × (852 ± 2) km × (513 ± 16) km. The mean value of the Haumea density, determined through the parameters of the triangular ellipsoid, and the mass determined by the orbital period of the Hi’iake satellite, is 1 885 ± 80 kg m−3. The geometric albedo of Haumea determined by our observations is 0.51, which is significantly smaller than the value of 0.804, as available in the most recent literature (Fornasier et al. 2013). Application of the atmospheric Cherenkov telescopes MAGIC for observing stellar occultations - In order to accurately determine the physical characteristics of small bodies by using the occultation method, a high temporal resolution of the detector is required. In order to improve the observational methods of stellar occultations, the use of the MAGIC (Major Atmospheric Gamma Imaging Cherenkov) telescopes was considered. With its sensitive central pixel, the MAGIC-II telescope has shown to be an excellent instrument for detecting millisecond flashes in the visible spectra. Compared to any other optical telescope used for observing stellar occultations, its central pixel with a temporal resolution of 10 kHz, combined with a large 17 m aperture, the MAGIC-II telescope enables reaching two orders higher resolutions. However, some of its limiting characteristics are the inability to control the sampling frequency, sensitivity only in the visible spectrum between 300 and 400 nm, and a low angular resolution (due to physically large pixels) responsible for a limitation in the apparent brightness of m = 13.5 ± 0.6 mag. In addition to determining the physical characteristics of small bodies, using the stellar occultation method enables us to determine the angular sizes of the occulted stars. Since stars are not point sources (they have a finite angular diameter), during the occultation of a stellar disk, its light curve does not show a sharp brightness drop but describes a Fresnel interference pattern whose details depend on the angular diameter of the occulted star. High sampling rates make it possible to record these interference patterns. Therefore, the high temporal resolution vii of the detector is the key for direct measurements of stellar radii. In this doctoral thesis, the method of determining stellar radii by observing Fresnel diffraction patterns that can be detected during stellar occultations is described. Models of the expected signal were performed, taking into account the characteristics of the MAGIC telescopes and the sensitivity of its detectors. Through observational proposals, telescope time was granted and first observations of stellar occultations with the MAGIC telescopes were acquired. Additionally, the effects of limb darkening of stellar disks were investigated. It was found that diffraction patterns formed by occultations of large disks with angular diameters of 0.7 mas and high limb darkening factors of u = 1.0 deviate in intensity up to approximately 5% from diffraction patterns of homogeneously illuminated stellar disks (u = 0.0). For stellar disks of smaller diameters or smaller limb darkening factors, the intensity deviations are smaller. These deviations in the intensity of diffraction patterns are reflected in the determination of the angular diameters of stellar disks. It was found that the angular radius of a homogeneously illuminated stellar disk, compared to a disk with a limb darkening factor of u = 1.0 taken into account, deviates by approximately 12.4%. Taking the limb darkening factors into account contributes to the accuracy of measurements of the angular diameters of stellar disks, but to achieve this accuracy, photometric measurements with uncertainties below 5% are required. Historically, almost all measurements of the stellar radii smaller than ∼1 arc millisecond have been performed by interferometric measurements. Measurements of stellar radii by observing occultations with asteroids allow reaching angular resolutions up to 0.1 milliarcseconds, which is at least a factor of two larger than the one available through interferometric measurements, and a factor of 10 larger than what can be achieved by observing lunar occultations. Therefore, the asteroid occultation method is extremely useful for measuring the angular diameters of stars below 1 milliarcsecond. In the period from December 2017 to February 2020, a total of 6 occultation observations with the MAGIC-II telescope were scheduled. Four observations were not successfully acquired due to bad weather or technical reasons. Two occultation events, those by the small bodies (83) Beatrix and (28) Bellona, were successfully acquired but resulted in a negative detection. Although the occultation events of (83) Beatrix and (28) Bellona occurred over sufficiently bright sources, and their probability of observation was estimated at 99%, the negative detections can be explained by a too small brightness drops, ∼1.5 mag for the (83) Beatrix event (2.5 ), and ∼0.9 mag for the (28) Bellona event (1.5 ). Based on the analysis presented in this thesis, we expect that any event with a brightness drop larger than 1.8-3.0 mag (3-5 above background noise) should be detected. Therefore, the observation campaign of occultations on MAGIC telescopes will be continued in the future
Genotyping of the roe deer, Capreolus capreolus (Linnaeus, 1758), major histocompatibility complex by next generation sequencing
No full textGeni glavnog sustava tkivne podudarnosti (eng. major histocompatibility complex, MHC)
jedni su od najvažnijih biomarkera za procjenu genetičke raznolikosti populacija jer su
izrazito varijabilni. Zbog uloge receptora MHC u vezanju i prikazivanju antigena novonastale
mutacije omogućuju otpornost jedinki na veći broj patogena i rezultiraju velikim brojem gena
i alela. Probleme u genotipizaciji predstavljaju višestruka polimorfna mjesta u alelima te je uz
tradicionalnu metodu sekvenciranja po Sangeru potrebno raditi predkorak molekularnog
kloniranja kako bi se razdvojile alelne faze. Metode sekvenciranja nove generacije (eng. next
generation sequencing, NGS) omogućuju zasebno, a istovremeno sekvenciranje velikog broja
fragmenata DNA te uvelike pojednostavljuju i ubrzavaju sam proces. Primjenila sam jednu od
metoda NGS, Ion Torrent S5, u genotipizaciji lokusa DRB sustava MHC srne (Capreolus
capreolus) kao primjera nemodelnog kralježnjaka. Umnožila sam egzon 2 lokusa DRB 14
uzoraka i napravila knjižnicu fragmenata za sekvenciranje. Dobivena očitanja analizirala sam
u programskom paketu AmpliSAT i identificirala sam osam alela od kojih je pet poznatih, a
tri su novootkrivena. Budući da u srna postoji samo jedan lokus DRB te su očitanja svakog
uzorka bila izrazito velike pokrivenosti rezultati su bili jasni i jednoznačni. Primjenjivost
tehnologije Ion Torrent potrebno je dalje testirati na uzorcima s udvostručenim lokusima te
usporediti s rezultatima drugih metoda sekvenciranja.Genes of the major histocompatibility complex (MHC) are one of the most important
biomarkers for assessment of genetic diversity of populations owing to their remarkable
polymorphism. Due to role of MHC receptors in antigen binding and presentation, new
mutations allow for resistance to a larger number of pathogens and result in a vast amount of
genes and alleles. Multiple polymorphic sites in alleles, on the other hand, pose problems for
successful genotyping by traditional methods and require application of molecular cloning in
addition to Sanger sequencing in order to resolve allele phases. Next generation sequencing
methods (NGS) have made possible sequencing of many DNA fragments individually, but in
massive parallel fashion, thereby simplifying and speeding up the whole procedure. In this
study I applied one of the NGS technologies, Ion Torrent S5, in genotyping MHC DRB locus
of roe deer (Capreolus capreolus) as one of the nonmodel vertebrates. I amplified second
exon of DRB locus in 14 individuals and constructed a sequencing library. I used online
program AmpliSAT for data analysis and I identified eight alleles, five of which are already
known and three that are new. Since roe deer has single DRB locus and sequencing yielded
reads with great coverage, analysis was simple and straightforward. Applicability of Ion
Torrent in genotyping needs to be further evaluated in species with duplicated DRB loci and
in comparison with results of different sequencing technologies
Impact of structural features on mechanical flexibility of crystals of one-dimensional cadmium(II) polymers with halides and pyridine and pyrazine derivatives
No full textU ovom diplomskom radu sintetizirani su koordinacijski polimeri kadmijevih(II) halogenida s
2-metilpirazinom (2-Mepz), 3-metilpiridinom (3-Mepy) i 4-metilpiridinom (4-Mepy). Devet
kompleksnih spojeva ([CdCl2(2-Mepz)]n (1), [CdBr2(2-Mepz)]n (2), [CdI2(2-Mepz)]n (3),
[CdCl2(3-Mepy)2]n (4), [CdBr2(3-Mepy)2]n (5), [CdI2(3-Mepy)2] (6), [CdCl2(4-Mepy)2]n (7),
[CdBr2(4-Mepy)2]n (8) i [CdI2(4-Mepy)2]n (9)) priređeno je klasičnom otopinskom sintezom, a
njihovi jedinični kristali uzgojeni su tehnikom nadslojavanja. Spojevi su analizirani metodama
termičke analize (TGA, DSC), infracrvenom spektroskopijom (IR) te difrakcijom rendgenskog
zračenja u praškastom uzorku (PXRD), a metodom difrakcije rendgenskog zračenja u
monokristalnom uzorku (SCXRD) analizirani su igličasti kristali. Također je ispitan i odziv
igličastih kristala priređenih spojeva na primjenu vanjske mehaničke sile te je u slučaju
elastično savitljivih kristala odziv i kvantificiran. U kristalnom pakiranju ustanovljene su
supramolekulske interakcije, π−interakcije i vodikove veze, te su pomoću njih objašnjeni odzivi
kristala na vanjsku mehaničku silu.This diploma thesis presents synthesis of coordination polymers of cadmium(II) halides with
2-methylpyrazine (2-Mepz), 3-methylpyridine (3-Mepy) and 4-methylpyridine (4-Mepy). Nine
complexes ([CdCl2(2-Mepz)]n (1), [CdBr2(2-Mepz)]n (2), [CdI2(2-Mepz)]n (3), [CdCl2(3-
Mepy)2]n (4), [CdBr2(3-Mepy)2]n (5), [CdI2(3-Mepy)2] (6), [CdCl2(4-Mepy)2]n (7), [CdBr2(4-
Mepy)2]n (8) and [CdI2(4-Mepy)2]n (9)) were synthesized using classical solution synthesis and
their single crystals were grown by the solvent layering technique. The products were
characterized by thermal methods (TGA, DSC), infrared spectroscopy (IR) and powder X-ray
diffraction (PXRD). The molecular and crystal structure of grown single crystals were
determined by single crystal X-ray diffraction analysis (SCXRD). Also, the response of needlelike crystals to external mechanical force was examined and, in the case of elastic flexibility,
the elastic response was quantified. Supramolecular interactions, namely, π−interactions and
hydrogen bonds, were determined in the crystal structure and were employed in rationalization
of the crystals responses to external mechanical force
Gas chromatography analysis of varietal thiols in wines with application of derivatization and stable isotope dilution analysis
No full textRazvijene su metode analize sortnih tiola u vinu. Sortni tioli i njihovi derivati akumulirani su ekstrakcijom na čvrstoj fazi i mikroekstrakcijom na čvrstoj fazi iz para iznad otopine. Optimirani su uvjeti derivatizacije etil-propiolatom i ekstrakcije sortnih tiola. Kalibracija je provedena tehnikom dodatka standarda u kombinaciji s tehnikom izotopnog razrjeđenja deuteriranim izotopomerima kao unutarnjim standardima. Kvalitativna i kvantitativna analiza sortnih tiola provedena je vezanim sustavom plinski kromatograf i tandemni spektrometar masa s trostrukim kvadrupolom uz praćenje višestrukih reakcija. Analiti su kvantificirani i detektorom kemiluminescencije sumpora te detektirani vezanim sustavom sveobuhvatne plinske kromatografije - spektrometrije masa. Po prvi puta određene su masene koncentracije sortnih tiola u hrvatskim vinima sorte Sauvignon bijeli, koje su bile u rasponu od 6,1 ng L-1 do 135,0 ng L-1. Istražen je utjecaj dodatka antioksidansa prilikom vinifikacije na koncentraciju sortnih tiola i očuvanje arome vina. Zastupljenost sortnih tiola bila je najviša kod tretmana vina kombinacijom kalijeva metabisulfita, askorbinske kiseline i galotanina, dok su najniže koncentracije izmjerene u vinima sumporenima dvostruko nižom dozom kalijeva metabisulfita u odnosu na kontrolu. Kombinacija antioksidansa potvrđuje sinergistički utjecaj askorbinske kiseline i sumporenja vina na očuvanje sortnih tiola radi sprječavanja reakcije tiola s kinonima.Methods for the analysis of varietal thiols in wines were developed and validated. Optimization conditions for the derivatization and extraction of varietal thiols was performed. Varietal thiols or derivatives thereof were extracted by solid-phase extraction or headspace solid-phase microextraction. Calibration was performed by standard addition combined with stable isotope dilution analysis with internal standards. The developed method was used for quantification of varietal thiols in wines by gas chromatography – tandem mass spectrometry with triple quadrupole and multiple reaction monitoring, by gas chromatography – sulfur chemiluminescence detector and for detection by comprehensive gas chromatography – mass spectrometry. For the first time, the mass concentration of varietal thiols in Croatian Sauvignon Blanc wines was determined, ranging from 6,1 ng L-1 to 135,0 ng L-1. The influence of addition of various antioxidants during the vinification step on the preservation of varietal thiols was investigated. The concentrations of thiols were highest in wines treated with a blend of potassium metabisulfite, ascorbic acid and gallotannins, while being lowest for the 50 % reduced sulfurization treatment. Synergistic effect of ascorbic acid and wine sulfurization on preservation of varietal thiols and inhibition of reaction with quinones was thereby confirmed