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Synthesis of amide derivative of a disubstituted ferrocene and desmuramyl-peptide
No full textU sklopu ovog diplomskog rada razvijen je sintetski put priprave amidnog derivata disupstituiranog ferocena i desmuramil-peptida (DMP). Ciljni spoj 10 je sintetiziran vezanjem također pripravljenih strukturnih motiva: O-benzilnog derivata disupstituirane ferocenkarboksilne kiseline 4 te tert-butilnog derivata DMP 8. Amidna veza između te dvije podjedinice ostvarena je pomoću pouzdane EDC/HOBt metode koja se često koristi u tu svrhu u peptidnoj kemiji. Spoj 4 je pripravljen prevođenjem polazne 1'-metoksikarbonilferocen-1-karboksilne kiseline u kiselinski klorid 1, zatim redukcijom spoja 1 s natrijevim borhidridom do alkohola 2, uvođenjem benzilne zaštite te saponifikacijom metilnog estera. Derivat DMP 8 je sintetiziran iz tert-butil- i Boc-zaštićene D-glutaminske kiseline koja je prvo pretvorena u izoglutaminski derivat 5 i amidnom vezom vezana na zaštićeni i aktivirani derivat L-alanina (Fmoc-L-Ala-OPfp) uz DIPEA kao bazu. Zatim je Fmoc skupina uklonjena s N-kraja spoja 7 uz oktan-1-tiol i DBU. Sintetski put priprave spoja 10 završava korakom uklanjanja benzilne zaštite sa spoja 9 hidrogenolizom. Provedena je strukturna karakterizacija svih sintetiziranih spojeva (1H i DEPTQ NMR spektroskopija, spektrometrija masa LC-MS). Ovako optimizirana metoda poslužit će za sintezu ostalih sličnih spojeva ove serije u budućim istraživanjima čiji je konačni cilj ispitivanje njihove adjuvantske aktivnosti.In this Thesis the synthetic route for the preparation of amide derivative of disubstituted ferrocene and desmuramyl peptide (DMP) was optimized. The target compound 10 was prepared by combining following, also prepared structural motifs: O-benzyl derivative of disubstituted ferrocene carboxylic acid 4 and tert-butyl DMP derivative 8. Amide bond between those two units was formed by reliable EDC/HOBt method which is often used in peptide chemistry for this purpose. Compound 4 was synthesized by converting 1'-methoxycarbonyl ferrocene-1-carboxylic acid to acyl chloride 1, reduction of 1 with sodium borohydride to alcohol 2, incorporation of benzyl protection and methyl ester saponification. DMP derivative 8 was prepared from tert-butyl and Boc protected D-glutamic acid which was converted to isoglutamine 5 first and then connected to protected and activated L-alanine (Fmoc-L-AlaOPfp) by an amide bond with DIPEA as a base. Fmoc group was removed from
N-terminus of 7 by 1-octanethiol and DBU. The synthetic route to target molecule 10 ends with benzyl protection removal from 9 by hydrogenolysis. Structural characterization of all compounds was performed by 1H and DEPTQ NMR spectroscopy as well as mass spectrometry (LC-MS). Optimized synthetic route presented here will serve for the preparation of similar compounds of this series for the final purpose of evaluating their adjuvant activity
Heating rate of the wall lizard (Podarcis muralis) and the blue-throated keeled lizard (Algyroides nigropunctatus) in laboratory conditions
No full textGušteri su ektotermni organizmi čija tjelesna temperatura ovisi o vanjskim izvorima
topline. Termoregulacija kod guštera uključuje kombinaciju fizioloških i bihevioralnih
mehanizama, a relativni doprinos tih mehanizama varira. Regulacija brzine apsorpcije topline
iz okoline ovisi o različitim čimbenicima, kao što su veličina i oblik tijela, površina izložena
sunčevom zračenju te boja i tekstura kože. Zidna gušterica (Podarcis muralis Laurenti, 1768)
je vrsta guštera koja preferira topla staništa te se obično nalazi na strmim liticama, krhotinama
i kamenim zidovima sa vegetacijom. S druge strane, mrki gušter (Algyroides nigropunctatus
Duméril & Bibron, 1839) preferira sunčana područja, često se nalazeći u sjenovitim ili
polusjenovitim područjima s degradiranom vegetacijom. S obzirom da ove dvije vrste guštera
preferiraju slična staništa te imaju slično obojenje tijela, cilj je istražiti utjecaj različite teksture
kože na brzinu zagrijavanja. Statistička obrada podataka uključivala je modeliranje pomoću
Gompertzove krivulje te sam za svakog guštera dobila procjenu parametara teorijske
maksimalne temperature (a), vremena najveće promjene temperature (b) i brzine zagrijavanja
(c). Dobiveni rezultati ukazuju da sama tekstura kože nema utjecaj na brzinu zagrijavanja, već
da na brzinu zagrijavanja vjerojatno utječe kombinacija morfoloških, fizioloških i bihevioralnih
čimbenika.Lizards are ectothermic organisms whose body temperature depends on external heat sources.
Thermoregulation in lizards involves a combination of physiological and behavioral
mechanisms, and the relative contribution of these mechanisms varies. The rate of heat
absorption from the environment depends on various factors, such as body size and shape, the
area exposed to solar radiation, and the color and texture of the skin. The wall lizard
(Podarcis muralis Laurenti, 1768) is a species of lizard that prefers warm habitats and is
usually found on steep cliffs, scree, and stone walls covered with vegetation. On the other
hand, the blue-throated keeled lizard (Algyroides nigropunctatus Duméril & Bibron, 1839)
prefers sunny areas, often found in shady or semi-shady areas with degraded vegetation.
Given that these two species of lizards prefer similar habitats and have similar body
coloration, the aim is to investigate the impact of different skin textures on the rate of
warming. Statistical data analysis involved modeling using the Gompertz curve, and for each
lizard, I obtained estimates of the theoretical maximum temperature (a), the time of greatest
temperature change (b), and the rate of warming (c). The results obtained indicate that the
skin structure itself does not affect the rate of warming, but rather the rate of warming is
probably affected by a combination of morphological, physiological, and behavioral factors
Modeling potential energy surfaces for benzene and its heterocyclic analogues using deep learning
No full textAnaliza ploha potencijalne energije (PES) predstavlja učinkovitu metodu istraživanja strukture i reaktivnosti organskih molekula. Točne reprezentacije tih ploha zahtijevaju brojne kvantno- kemijske proračune energije za različite konfiguracije ispitivanog sustava te analitički opis ploha, a cijeli postupak može se značajno ubrzati korištenjem strojnog i dubokog učenja. Najefikasniji opis PES-ova dobije se razapinjanjem ploha prema odgovarajućim normalnim koordinatama koristeći razvoj u ovisnosti o dimenziji prostora. U okviru ovog diplomskog rada provedeno je teorijsko istraživanje ploha potencijalne energije benzena i njegovih heterocikličkih analoga: piridina, piridazina, pirimidina i pirazina korištenjem kvantno-kemijskih proračuna te algoritama strojnog i dubokog učenja. Optimizacije geometrija i izračuni vibracijskih frekvencija su za sve istraživane sustave provedeni na razini teorije B3LYP-D3/aug-cc-pVTZ. Za ispitivanje 1- i 2- dimenzijskih presjeka PES-a razapetih po pripadajućim normalnim koordinatama generirane su sve relevantne strukture ispitivanih molekula korištenjem programa qcc te su provedeni kvantno- kemijski proračuni energija. Korištenjem algoritama strojnog i dubokog učenja implementiranih u program moonee određeni su najbolji mogući regresijski modeli koji opisuju odabrane presjeke PES-ova. Dobiveni analitički izrazi za opis potencijala iskoristit će se za buduće simulacije molekularne dinamike i vibracijsku analizu.The analysis of potential energy surfaces (PES) is an effective method for investigating the structure and reactivity of organic molecules. Accurate representations of these surfaces require numerous quantum- chemical energy calculations for different configurations of the studied system and an analytical description of the surfaces. The entire process can be significantly accelerated by using machine learning and deep learning methods. The most efficient description of PES is obtained by spanning the surfaces according to the appropriate normal coordinates and using adequate expansion depending on the dimensionality of the space. In this thesis, theoretical research was conducted on the potential energy surfaces of benzene and its heterocyclic analogs: pyridine, pyridazine, pyrimidine, and pyrazine, using quantum-chemical calculations and machine learning and deep learning algorithms. Geometry optimizations and vibrational frequency calculations for all studied systems were performed at the B3LYP-D3/aug-cc-pVTZ level of theory. To investigate 1- and 2-dimensional sections of the PES spanned by the corresponding normal coordinates, all relevant structures of the studied molecules were generated using the qcc program, and quantum-chemical energy calculations were carried out. Using machine learning and deep learning algorithms implemented in the moonee program, the best possible regression models describing the selected sections of PESes were determined. The obtained analytical expressions for the description of potentials will be used for future molecular dynamics simulations and vibrational analysis
Transverse single spin asymmetry in high-energy hadron collisions
No full textU ovom diplomskom radu radimo numerički račun asimetrije jednog poprečnog spina (STSA) AN u visokoenergetskim sudarima polariziranih protona s protonima pp -> hX i težim jezgrama pA -> hX prilikom produkcije pi+ i pi0 piona. Računamo fragmentacijski doprinos asimetriji te koristimo hibridni pristup koji spaja kolinearni formalizam s efektivnom teorijom staklastog kondenzata boje. U računu su korišteni podaci s RHIC sudarivača. Pronalazimo da dodavanja članova koji sadrže fragmentacijsku funkciju ~H pozitivno dodaje asimetriji, međutim ne mijenja njenu nuklearnu ovisnost.In this work we present a numerical calculation of the single spin asymmetry (STSA) AN in forward pi+ & pi0 pion production in polarized proton-proton and proton-nucleus collisions. We calculate the fragmentation contribution to the asymmetry in the hybrid approach which combines the collinear twist-3 framework with the color-glass condensate effective field theory. In our calculation we use the data supplied from the RHIC accelerator. We find that the asymmetry is enlarged when the
~H fragmentation function is added. The nuclear dependance of our result is not changed upon adding this function
Bloom and assemblage composition of coccolithophores in the Northern Atlantic
No full textU ovom su radu obrađeni podaci o brojnosti i raznolikosti vrsta kokolitoforida, kao i fizikalni i kemijski parametri uzoraka morske vode uzeti na području sjevernog Atlantika na četiri različite postaje u srpnju 2018. s ciljem interpretacije cvata i sastava zajednice kokolitoforida na istraživanom području. Zaključeno je da su se tri postaje nalazile na kontinentskom šelfu, a preostala jedna na kontinentskoj padini. Na postaji na kojoj je zabilježen vrhunac cvata kokolitoforida dominirala je vrsta Gephyrocapsa huxleyi HET uz koju su značajne bile Syracosphaera origami HOL, Syracosphaera corolla HET, Rhabdosphaera xiphos HET i Ophiaster formosus HET.In this paper, data on the abundance and diversity of coccolithophorid species, as well as the physical and chemical parameters of seawater samples taken in the North Atlantic area at four different stations in July 2018, were processed with the aim of interpreting the flora and composition of the coccolithophorid community in the research area. It was concluded that three stations were located on the continental shelf, and the remaining one was on the continental slope. At the station where the peak of the coccolithophorid bloom was recorded, the species Gephyrocapsa huxleyi HET dominated, along with Syracosphaera origami HOL, Syracosphaera corolla HET, Rhabdosphaera xiphos HET and Ophiaster formosus HET
Effects of fluorescent indole derivates on the cell cycle regulation and survival of human adenocarcinoma cells and lung fibroblast cells
No full textFluorescentni indolni kationi zanimljivi su za terapeutsku upotrebu jer pokazuju jaku fluorescenciju i lokalizaciju u mitohondrijima. Modifikacijom indolnog prstena ovih spojeva, moguće je poboljšati njihova svojstva, poput fotostabilnosti i protutumorske aktivnosti, čime se povećava njihova učinkovitost u terapijama. Cilj ovog diplomskog rada bio je ispitati učinak novo sintetiziranih derivata indola na bazi vinil piridina na stanični ciklus, preživljenje, ekspresiju proteina uključenih u preživljavanje i regulaciju staničnog ciklusa te ispitati sposobnost lokalizacije spojeva u mitohondrijima stanica adenokarcinoma (A549) i fibroblasta pluća čovjeka (WI-38). Tretman stanica A549 i WI-38 spojevima FB404, FB411, FB414 i FB417 uzrokuje smanjenje preživljenja stanica. Smanjeno preživljenje stanica nakon tretmana spojevima nije uzrokovano aktivacijom apoptoze. Nadalje, spojevi FB404, FB406, FB411, FB414 i FB417 pokazuju značajnu lokalizaciju u mitohondrijima stanica A549 i WI-38. Tretman stanica A549 spojevima FB404, FB411, FB414 i FB417 uzrokuje zastoj u G0/G1 fazi staničnog ciklusa koji je vjerojatno posljedica povećane ekspresije proteina p21.Fluorescent indole cations are of great interest for therapeutic use because they show strong fluorescence and localization in mitochondria. By modifying the indole ring of these compounds, it is possible to improve their properties, such as photostability and antitumor activity and therefore increase their effectiveness in therapies. The aim of this thesis was to examine the effect of newly synthesized indole derivatives based on vinyl pyridine on the cell cycle, survival, expression of proteins involved in survival and regulation of the cell cycle, and to examine the ability of the compounds to localize in the mitochondria of adenocarcinoma cells (A549) and human lung fibroblasts (WI-38). Treatment of A549 and WI-38 cells with compounds FB404, FB411, FB414 and FB417 causes a decrease in cell survival. Decreased cell survival after compound treatment was not caused by activation of apoptosis. Furthermore, the compounds FB404, FB406, FB411, FB414 and FB417 show significant localization in the mitochondria of A549 and WI-38 cells. Treatment of A549 cells with compounds FB404, FB411, FB414 and FB417 causes arrest in the G0/G1 phase of the cell cycle, which is probably due to increased expression of the p21 protein
Biochemical and molecular responses of thale cress (Arabidopsis thaliana) to short-term heat shock
No full textToplinski stres smatra se jednim od glavnih abiotičkih faktora koji negativno utječu na rast i razvoj biljaka. Cilj ovog rada bio je istražiti biokemijski i molekularni odgovor klijanaca uročnjaka (Arabidopsis thaliana) na toplinski šok određivanjem sadržaja H2O2, stupnja lipidne peroksidacije, fotosintetske učinkovitosti, količine enzima RuBisCO, indukcije proteina toplinskog šoka HSP90 i ekspresije nekoliko gena uključenih u odgovor na toplinski stres. Uzorci su analizirani odmah nakon izlaganja klijanaca temperaturi od 45 °C u trajanju 45 minuta te nakon oporavka u ukupnom trajanju 11 sati i 15 minuta. Rezultati su pokazali da neposredno nakon tretmana, a niti nakon oporavka, nije došlo do značajnog porasta količine H2O2 i stupnja lipidne peroksidacije, tj. na temelju spomenutih parametara nije potvrđen oksidacijski stres. Fotosintetska učinkovitost bila je smanjena, uz povećano rasipanje energije, što sugerira oštećenje fotosustava II (PSII). Primijenjeni tretman nije djelovao na količinu enzima RuBisCO. Potvrđena je indukcija proteina HSP90 te pojačana ekspresija gena HSFA3 i DREB2A. Dobiveni rezultati potvrđuju da su klijanci uročnjaka pokazali biokemijske i molekularne promjene nakon izlaganja toplinskom šoku, pružajući osnovu za daljnje istraživanje koje bi se temeljilo na uzorkovanju u više vremenskih točaka nakon tretmana te mjerenju aktivnosti antioksidacijskih enzima i količine neenzimskih antioksidansa.Heat stress is considered one of the most important abiotic factors that affect plant growth and development. The aim of this work was to investigate the biochemical and molecular responses of the Arabidopsis thaliana seedlings to heat shock by determining the content of H2O2, the level of lipid peroxidation, the photosynthetic efficiency, the amount of the enzyme RuBisCO, the induction of heat shock proteins HSP90 and the expression of several genes involved in the response to heat stress. Samples were analyzed immediately after a 45-minute heat treatment at 45 °C and after a recovery period of 11 hours and 15 minutes. The results showed no significant increase in the amount of H2O2 and lipid peroxidation, i.e. oxidative stress was not confirmed by the mentioned parameters. Photosynthetic efficiency was reduced, with increased energy dissipation, indicating damage of photosystem II (PSII). The amount of RuBisCO enzyme was not changed. Induction of HSP90 proteins and increased expression of HSFA3 and DREB2A genes were confirmed. The results obtained show biochemical and molecular changes in A.thaliana seedlings after heat shock exposure and provide a basis for further research based on sampling at multiple time points and measuring the activity of antioxidant enzymes and the content of non-enzymatic antioxidants
Genetic and morphological diversity of the cave spider species Stalagtia hercegovinensis
No full textDinarski krš jedna je od svjetskih točaka najveće špiljske bioraznolikosti. Kao i ostali špiljski
organizmi, određene skupine pauka također pokazuju karakteristične prilagodbe na život u
špiljskim uvjetima kao što su depigmentacija i redukcija očiju. Jedan od takvih pauka je vrsta
Stalagtia hercegovinensis iz porodice Dysderide, potporodice Harpacteinae. Rasprostranjena
je u južnim Dinaridima, od Nacionalnog parka Krka na sjeveru do Crne Gore na jugu. Ovako
veliki areal nekarakterističan je za potpuno prilagođenu špiljsku vrstu što podiže sumnje da je
S. hercegovinensis zapravo kompleks vrsta. Za potvrdu ove hipoteze, izolirana je DNA te su
umnoženi i sekvencirani geni COI, 16S, 18S, 28S i H3 od 68 jedinki S. hercegovinensis koje
su prikupljene u cijelom njezinom arealu. Filogenetske analize i delimitacijske metode
potvrdile su postojanje šest podržanih, monofiletskih i geografski razdvojenih skupina.
Detaljnim morfološkim analizama jedinki svake skupine utvrđene su razlike u morfologiji
spolnih organa, broju i rasporedu četina na segmentima prvog para nogu te stupnju redukcije
ostataka očiju. Utvrđeni morfološki karakteri pokazali su se većinom konzistentni za
razlikovanje pojedinih skupina. U jednom špiljskom lokalitetu otkrivena je sintopija dvije
različite skupine, pojava koja je izuzetno rijetka za špiljske pauke. Ovim istraživanjem stvoreni
su temelji za budući opis novih vrsta iz kompleksa S. hercegovinensis.Dinaric karst is one of the global centers of underground biodiversity. As well as other
underground organisms, certain groups of spiders show characteristic adaptations to
underground conditions such as depigmentation and eye reduction. One such species is
Stalagtia hercegovinensis, from the family Dysderidae, subfamily Harpacteinae. It is
distributed in the southern Dinarides, from National Park Krka in the north, to Montenegro in
the south. Such a large areal is unusual for cave adapted species, and raises a doubt that S.
hercegovinensis is a species complex. To test that, DNA of 68 specimens of S. hercegovinensis
was isolated and genes COI, 16S, 18S, 28S and H3 were amplified and sequenced.
Phylogenetic analyses and species delimitation methods confirmed the existence of six well
supported and geographically separated groups. Morphological analyses revealed discernible
differences regarding the morphology of reproductive organs, the number and distribution of
spines on anterior legs, and the degree of eye reduction. Observed morphological characters
proved consistent in differentiating each group from one another. In one cave locality, a
sintopic relationship between two groups was discovered, a most rare occurrence for cave
spiders. This research established a foundation for descriptions of new cave spider species in
S. hercegovinensis complex
ANTIAGGREGATORY EFFECT OF PROPOLIS AND SELECTED LAMIACEAE SPECIES
No full textKardiovaskularne bolesti vodeći su uzrok smrti u razvijenim zemljama. Budući da u patološkim procesima koji dovode do kardiovaskularnih događaja sudjeluju trombociti, sve se više istražuju antiagregacijska svojstva tvari prirodnog podrijetla. Pokazalo se da flavonoidi u koncentracijama koje se mogu postići u krvi nakon konzumacije hrane bogate polifenolima mogu utjecati na agregaciju trombocita. Propolis i biljne vrste porodice Lamiaceae obiluju polifenolnim spojevima. Provedena je kemijska karakterizacija 21 uzorka propolisa različitog podrijetla te 24 ekstrakta devet vrsta porodice Lamiaceae (Melissa officinalis, Salvia officinalis, Rosmarinus officinalis, Lavandula angustifolia, Salvia brachyodon, Ocimum basilicum, Origanum vulgare, Calamintha nepeta L., Mentha x piperita) s ciljem identifikacije i kvantifikacije njihovih biološki aktivnih spojeva (spektrofotometrijske metode, HPLC, LC-MS). Antiagregacijski učinak ispitan je impedancijskom agregometrijom u punoj krvi dodatkom ADP-a kao induktora agregacije, a antioksidacijski učinak DPPH testom. Svi ispitivani uzorci pokazuju statistički značajno smanjenje agregacije trombocita u mikromolarnim koncentracijama. Dokazana je korelacija između sadržaja pojedinih polifenolnih sastavnica i biološkog učinka ispitivanih uzoraka (antiagregacijski i antioksidacijski učinak).Cardiovascular diseases are the leading cause of death in developed countries. Since platelets are involved in the pathological processes leading to cardiovascular events, the antiplatelet properties of substances of natural origin are increasingly being investigated. It has been shown that flavonoids in concentrations that can be achieved in the blood after eating foods rich in polyphenols can affect platelet aggregation. Propolis and plant species of the Lamiaceae family are rich in polyphenols. Chemical characterization of 21 samples of propolis of various origins and 24 extracts of nine species of the Lamiaceae family (Melissa officinalis, Salvia officinalis, Rosmarinus officinalis, Lavandula angustifolia, Salvia brachyodon, Ocimum basilicum, Origanum vulgare, Calamintha nepeta, Mentha x piperita) was carried out with the aim of identifying and quantifying their biologically active compounds (spectrophotometric methods, HPLC, LC-MS). The antiplatelet effect was investigated by impedance aggregometry in whole blood with the addition of ADP as an inducer of aggregation, and the antioxidant effect by DPPH assay. All tested samples showed a statistically significant decrease in platelet aggregation at micromolar concentrations. A correlation between the content of individual polyphenolic components and the biological effect of the tested samples (antiplatelet and antioxidant effect) has been demonstrated
The construction of spatial identities in the branding of Croatian tourism: an analysis of the Croatian National Tourist Board's promotion
No full textProstorni identiteti aktualna su tema u znanosti i turizmu. U uvjetima jake turističke konkurencije i utjecaja procesa poput globalizacije, turističke destinacije gotovo su prisiljene razvijati vlastiti turistički identitet i brend kako bi stvorili razlikovnu i konkurentsku prednost na tržištu. U suvremeno doba, isto vrijedi i na razini država, gdje je razvijanje snažnog i prepoznatljivog brenda ključno u raznim sferama, sagleda li ih se prvotno kao destinacije ili ne. Kao jedna od sve popularnijih i sve češće korištenih metoda u znanosti, analiza sadržaja diči se objektivnošću i sustavnošću pri istraživanju širokog spektra društvenih pojava i oblika komunikacije. S ciljem objektivnog sagledavanja konstruiranih prostornih identiteta u brendiranju turizma Hrvatske, ovaj rad koristi metodu analize sadržaja za istraživanje promotivnih materijala Hrvatske turističke zajednice. Hrvatska turistička zajednica je krovna državna organizacija koja stvara, oblikuje i razvija identitet i brend turizma Hrvatske. Rezultati analize sadržaja pokazali su kako se konstruirani prostorni identiteti u brendiranju turizma Hrvatske temelje na ljepoti prirodnih i kulturnih elemenata turističke ponude.Spatial identities are a current topic in science and tourism. In the conditions of strong tourism competition and the impact of processes such as globalization, tourist destinations are almost forced to develop their own tourist identity and brand in order to create a distinctive and competitive advantage in the market. In modern times, the same is true at the national level, where developing a strong and recognizable brand is crucial in various spheres, whether they are primarily perceived as destinations or not. As one of the increasingly popular methods in science, content analysis prides itself on its objectivity and systematization in researching a wide range of social phenomena and forms of communication. With the aim of objectively defining the constructed spatial identities in the branding of Croatian tourism, this paper uses the method of content analysis to research the Croatian National Tourist Boards promotional materials. The Croatian National Tourist Board is an state umbrella organization that creates, shapes and develops the identity and brand of Croatian tourism. The results of the content analysis revealed that the constructed spatial identities in the branding of Croatian tourism are based on the beauty of natural and cultural elements of its tourist offer