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Facies and biostratigraphy of Cretaceous deposits from Gacko area, Bosnia and Herzegovina
No full textCilj ovog diplomskog rada bila je mikrofacijesna i mikropaleontološka analiza krednih naslaga sjeveroistočno od Gackog, Bosna i Hercegovina. Unutar donjokrednih naslaga određena su 3 mikrofacijesa koji odgovaraju facijesnim zonama zaštićene unutarnje platforme i otvorene platforme. Starost ovih naslaga određena je kao barem–apt na temelju biostratigrafskog raspona bentičke foraminifere Palorbitolina sp. Unutar baremsko–aptskih naslaga zastupljeni su ekstraklasti koji upućuju na trošenje paleokopnenih područja s vapnencima donjojurske starosti. Između donjokrednih i gornjokrednih naslaga utvrđena je transgresivna granica. Unutar gornjokrednih naslaga određena su 3 mikrofacijesa koji odgovaraju rasponu facijesnih zona od otvorene platforme preko padine do podnožja padine. Mala debljina plitkomorskih gornjokrednih naslaga koje prelaze u pelagičke vapnence padine ukazuje na relativno brzu transgresiju s tektonskim utjecajem. Starost gornjokrednih naslaga je santon–donji kampan, utvrđena na temelju biostratigrafskih raspona određenih pelagičkih foraminifera. Unutar santonsko– donjokampanskih naslaga zastupljeni su ekstraklasti koji su rezultat trošenja paleokopna te intraklasti koji upućuju na pretaloživanje unutar taložnog prostora.This thesis focuses on the microfacies and biostratigraphic analysis of Cretaceous deposits northwest of Gacko, Bosnia and Herzegovina. Within the lower Cretaceous deposits 3 microfacies types were determined, which correspond to restricted and open marine facies zones. The age of the lower Cretaceous deposits is determined as Barremian–Aptian, based on the benthic foraminifera Palorbitolina sp. Extraclasts within the Barremian–Aptian deposits indicate the existence of contemporaneous land areas from which lower Jurassic limestones were being eroded. Lower Cretaceous deposits are unconformably overlain by upper Cretaceous deposits, the age of which has been determined as Santonian–lower Campanian, based on the biostratigraphic ranges of identified planktonic foraminifera. Within the upper Cretaceous deposits 3 microfacies types were determined, which correspond to facies zones ranging from open marine, slope to toe–of–slope. The small thickness of upper Cretaceous shallow–water deposits which pass vertically into pelagic limestones indicates that the transgression was relatively rapid and tectonically controlled. Within the Santonian–lower Campanian deposits, extraclasts of older limestones were identified, as well as intraclasts which point to re–sedimentation processes within the depositional environment
Application of the smart pebbles method in monitoring of morphodynamics on the Ploče beach (Rijeka)
No full textProvedeno je istraživanje morfodinamike umjetne šljunčane plaže Ploče tijekom proljeća 2022. godine primjenom metode pametnih RFID valutica. Metodom UAV-SfM-MVS fotogrametrije, dGPS profiliranjem plaže, granulometrijskom i morfometrijskom analizom sedimenta te faznom analizom pomoću rendgenske difrakcije na prahu je dobiven sedimentološki i morfološki kontekst istraživane plaže prema kojem su rezultati metode pametnih valutica interpretirani. Srednja veličina zrna sedimenta plaže iznosi Md = 39 mm te je uočen trend pokrupnjavanja od SZ prema JI, uz iznimku područja proboja podzemnih voda gdje je uzorkovan sitni sediment s Md = 2,4 mm, sastavljen dominantno od kalcita. Kratkoročne morfološke promjene ukazuju na prevladavajući utjecaj zapljuskivanja valova u okviru plimnih uvjeta, a dugoročne ukazuju na akumulaciju sitnijeg sedimenta na SZ dijelu plaže te krupnijeg u zoni beach step-a što je uvjetovano nagibom intertajdala i sedimentnim karakteristikama okolnih valutica. Erozija je najizraženija na području proboja podzemnih voda. Pozicija berme se mijenja ovisno o dosegu valova tijekom nevremena, a pri mirnim uvjetima ovisno o morskim mijenama koje određuju doseg valova.Morphodynamics study of the artificial pebble beach Ploče was conducted during the spring of 2022 using the “smart pebbles” RFID method. UAV-SfM-MVS photogrammetry, dGPS beach profiling, granulometric and morphometric sediment analysis, and X-ray powder diffraction mineral phase analysis provided the sedimentological and morphological context of the studied beach for the interpretation of the smart pebbles method results. Median grain size of the beach sediment is Md = 39 mm, and a coarsening trend was observed from NW to SE, with the exception of the groundwater seeping area where the finer sediment, of Md = 2.4 mm, composed predominantly of calcite, was sampled. Short-term morphological changes indicate the predominant influence of swash action during various tidal conditions. Long-term changes indicate the accumulation of mostly coarse pebbles on the NW part of the beach and cobbles on the beach step, depending on the intertidal slope steepness and the sedimentary characteristics of the surrounding pebbles. Erosion is the most prominent in the area of groundwater seeping. The positions of berms change depending on the storm wave run-up and fair-weather run-up modified by tidal conditions
An untargeted metabolomic approach for the purpose of detecting the effect od duloxetine and bright light therapy in patients diagnosed with major depressive disorder
No full textVeliki depresivni poremećaj ozbiljan je mentalni poremećaj koji značajno narušava kvalitetu života, radnu sposobnost te interpersonalne odnose. Očituje se dugotrajnim lošim raspoloženjem, gubitkom interesa, smanjenjem energije te kognitivnim i somatskim simptomima. Farmakološka terapija najčešće uključuje antidepresive iz skupine selektivnih inhibitora ponovne pohrane serotonina i noradrenalina, poput duloksetina, dok se u nekim slučajevima primjenjuju i nefarmakološke metode poput fototerapije. Metabolomika, interdisciplinarna znanost koja se bavi analizom metabolita u biološkim uzorcima, pruža uvid u biokemijske promjene ovog poremećaja. Neciljano metabolomsko profiliranje plazme pacijenata omogućuje identifikaciju biomarkera povezanih s patofiziologijom poremećaja i odgovorom na terapiju. Tehnologije poput plinske kromatografije spregnute sa spektrometrijom mase ključne su za analizu metabolita, omogućujući detekciju i kvantifikaciju promjena u metabolizmu lipida, aminokiselina i energetskih puteva. Univarijatna i multivarijatna statistička obrada rezultirala je sa značajno promijenjenim zastupljenostima metabolita unutar ispitivanih skupina koji služe kao biomarkeri za prilagodbu i odabir strategije liječenja velikog depresivnog poremećaja.Major depressive disorder is a severe mental disorder that significantly impairs quality of life, work capacity, and relationships. It manifests as prolonged low mood, loss of interest, reduced energy, and cognitive and somatic symptoms. Treatment often includes antidepressants inhibiting serotonin and norepinephrine reuptake, such as duloxetine, while non- pharmacological methods like phototherapy are sometimes used. Metabolomics, an interdisciplinary science analyzing metabolites in biological samples, provides insight into the biochemical changes of this disorder. Untargeted metabolomic profiling of patient plasma enables the identification of biomarkers associated with the disorder's pathophysiology and response to therapy. Technologies such as gas chromatography-mass spectrometry are crucial for metabolite analysis, allowing the detection and quantification of changes in lipid, amino acid, and energy metabolism. Univariate and multivariate statistical analysis revealed significantly altered metabolite levels within the studied groups, serving as biomarkers for optimizing and selecting treatment strategies for major depressive disorder
Virusi današnjice – prevencija, dijagnostika i liječenje
No full textOvaj dokument nastao je kroz projekt “Molekularna raznolikost virusa Epstein-Barr” (IP-2020-02-8961), financiran od Hrvatske zaklade za znanost, kao materijal za neformalno obrazovanje koje je dio cjeloživotnog obrazovanja
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
Lukomir-the last Bosnian and Herzegovinian village
No full textRuralna su područja često u povijesti privlačila ljude u svrhu provođenja dokolice, tako i danas ona ulaze u uži krug interesa sve većeg broja turista. Planina i krš daju mogućnosti primanja turista cijele godine, te zbog toga Bosna i Hercegovina treba uložiti u razvoj i proširenje ponude ruralnog turizma. Jedna od vodećih lokacija ruralnog turizma u Bosni i Hercegovini jest selo Lukomir, koje se nalazi na planini Bjelašnici. Lukmir je poseban po svojoj baštini i tradiciji polunomadskog načina života, te je ujedno najizoliranije selo u državi. Rad se bavi opisom nastanka sela i njegove baštine, te očuvanja autentičnosti kroz razvoj u modernom turizmu i njegov utjecaj na opstanak sela.Rural areas have often attracted people in history for the purpose of spending leisure time, so even today they enter the narrow circle of interests of an increasing number of tourists. The mountain and the karst provide opportunities to receive tourists all year round, and for this reason, Bosnia and Herzegovina should invest in the development and expansion of the offer of rural tourism. One of the leading locations of rural tourism in Bosnia and Herzegovina is the village of Lukomir, located on the Bjelašnica mountain. Lukmir is special for its heritage and tradition of a semi-nomadic way of life, and it is also the most isolated village in the country. The master thesis deals with the description of the origin of the village and its heritage, as well as the preservation of authenticity through the development of modern tourism and its influence on the survival of the village
Mechanochemical synthesis of coordination compounds of copper(II) with amino acids containing aliphatic side chains
No full textU sklopu diplomskog rada ispitani su mehanokemijski postupci sinteze koordinacijskih
spojeva bakra(II) i aminokiselina s alifatskim bočnim ograncima. Koristeći LAG metodu,
odnosno otapalom potpomognuto mljevenje, uspješno su pripravljeni koordinacijski spojevi
Cu(L-Ala)2, Cu(L-Leu)2, Cu(L-Ile)2, Cu(L-Val)2, Cu(L-Pro)2 i ternarni spojevi Cu(L-Ala)(L-Ile)
i Cu(L-Ala)( L-Val). Prilikom sinteza ternarnih spojeva, u 8 od 10 sinteza su dobiveni
koordinacijski spojevi bakra s istovrsnim aminokiselinama, što ukazuje na selektivnost Cu(II)
iona prema aminokiselinama, koja prati sljedeći trend: L-Leu ≈ L-Pro > L-Ile ≈ L-Val > L-Ala.
Produkti su karakterizirani koristeći spektroskopiju IR (tehnika ATR) i rendgensku difrakciju
u polikristalnom uzorku. Produkti trans-Cu(L-Val)2 i cis-Cu(L-Ile)2(H2O) su karakterizirani i
rendgenskom difrakcijom na monokristalnom uzorku te su određene molekulske i kristalne
strukture. U slučaju trans-bis(L-valinato)bakra(II), metalni centar ima oktaedarsku
koordinaciju uz deformaciju geometrije što je posljedica Jahn-Tellerovog efekta. Kod cisbis(L-izoleucinato)bakra(II) je metalni centar pentakoordiniran te je geometrija kvadratno
piramidalna.This diploma thesis presents an investigation of mechanochemical synthesis of coordination
compounds of copper(II) and amino acids containing aliphatic side chains. Using the LAG
method (liquid assisted grinding), the following compounds were successfully obtained:
Cu(L-Ala)2, Cu(L-Leu)2, Cu(L-Ile)2, Cu(L-Val)2, Cu(L-Pro)2, Cu(L-Ala)( L-Ile) and
Cu(L-Ala)(L-Val). When trying the synthesis of ternary compounds, coordination compounds
of copper with identical amino acids were obtained in 8 out of 10 syntheses, which indicates
the selectivity of Cu(II) ions towards amino acids, which follows the trend: L-Leu ≈ L-Pro >
L-Ile ≈ L-Val > L-Ala. Obtained complexes were identified using IR spectroscopy (ATR
technique) and powder X-ray diffraction. Molecular and crystal structures of trans-Cu(L-Val)2
and cis-Cu(L-Ile)2(H2O) were deermined using single crystal X-ray diffraction. Jahn-Teller
effect was noticed as the geometry of copper ion in trans-Cu(L-Val)2 is distorted octahedral,
whereas in the case of cis-Cu(L-Ile)2(H2O) the copper ion is pentacoordinated and the
geometry is square pyramidal
Synthesis of quaternary O-methyloximes ; Enzyme-properties research - examples of teaching practice
No full textOvaj diplomski rad sastoji se od istraživačkoga i metodičkog dijela. U istraživačkom dijelu opisana je priprava O-metiloksima kinuklidin-3-ona klasičnom sintezom te primjenom mehanokemije i mikrovalnog zračenja. Spoj je pripravljen reakcijom hidrokloridnih soli kinuklidin-3-ona i metoksiamina bez dodatka baze. Kvaternizacijom kinuklidinskog dušikova atoma pripravljenog Ometiloksima s metil-jodidom, benzil-bromidom te različito supstituiranim benzil-bromidima (nitro skupine i atomi halogena u meta i para položaju) pripravljena je serija od 10 novih kvaternih derivata kinuklidin-3-on-O-metiloksima. Reakcije su praćene spektroskopijom ATR. Pripravljenim spojevima koji do sada nisu opisani u literaturi, određeno je talište te su strukture dobivenih spojeva potvrđene spektrometrijom masa, infracrvenom spektroskopijom, te 1D i 2D spektroskopijom NMR. Cilj metodičkog dijela rada je potaknuti nastavnike kemije na kreativnost u nastavi temeljenoj na učenju otkrivanjem unutar koncepta Enzimi. Navedena tema je izborni sadržaj u novom kurikulumu Kemije četvrtoga razreda gimnazije. Osmišljen je pokus na temelju kojega su oblikovani metodičkodidaktički materijali za jedan 90-minutni nastavni sat. Pri tome su postavljeni odgojno-obrazovni ciljevi temeljeni na prethodnim učeničkim znanjima, vještinama i sposobnostima.This thesis consists of a research and methodological part. The research part describes the preparation of O-methyloxime of quinuclidin-3-one by classical synthesis and the application of mechanochemistry and microwave radiation. The compound was prepared by the reaction of hydrochloride salts of quinuclidin-3-one and methoxyamine without the addition of a base. By quaternization of the quinuclidine nitrogen atom of prepared O-methyloxime with methyl iodide, benzyl bromide and differently substituted benzyl bromides (nitro groups and halogen atoms in the meta and para positions), a series of 10 new quaternary derivatives of quinuclidine-3-one-O-methyloxime was prepared. The reactions were monitored by ATR spectroscopy. The melting points of the prepared compounds, which have not been described in the literature so far, was determined, and the structures of the obtained compounds were confirmed by mass spectrometry, infrared spectroscopy, and 1D and 2D NMR spectroscopy. The goal of the methodological part of thesis is to encourage chemistry teachers to be creative in teaching based on learning through discovery within the concept of Enzymes. The mentioned topic is an optional content in the new chemistry curriculum of the fourth grade of high school. An experiment was designed on the basis of which methodological and didactic materials were designed for one 90-minute lesson. In doing so, educational goals were set based on previous student knowledge, skills and abilities
Development and validation of a new bioanalytical method for simultaneous determination of ribociclib, letrozole and ibuprofen by capillary electrophoresis
No full textRak dojke, s dominantnim podtipom HR+ HER2−, najčešći je rak u svijetu. Jedan od načina liječenja HR+ HER2− raka dojke je kombinacijom CDK4/6 inhibitora i inhibitora aromataze, često uz lijekove ribociklib i letrozol. Kapilarna elektroforeza metoda je koja se iz dana u dan sve više razvija te bi se s odgovarajućom reproducibilnošću i osjetljivošću mogla koristiti u svrhu terapijskog praćenja lijekova. U ovom je radu razvijena i validirana metoda za određivanje ribocikliba, letrozola i ibuprofena kapilarnom elektroforezom uz ketoprofen kao unutarnji standard. Separacija je postignuta uz 75 mmol dm−3 fosfat, 8,5 mmol dm−3 sulfobutileter-β-ciklodekstrin (SBE-β-CD) i 5 % izopropanola u radnom puferu pri naponu 15 kV i temperaturi 25 °C. Uzorak je injektiran hidrodinamički pri tlaku −50 mbar u trajanju 5 sekundi, nakon injektiranja ultračiste vode 6 sekundi. Metoda je precizna, linearna u rasponu masene koncentracije od 1 do 75 µg cm−3, specifična, robusna za promjenu temperature, koncentracije SBE-β-CD te napona.Breast cancer is the most common type of cancer in the world, with subtype HR+ HER2− being most prevalent. HR+ HER2− breast cancer can be treated with hormone therapy, with ribociclib (CDK 4/6 inhibitor) and letrozole (aromatase inhibitor) being a commonly used medicine combination. Capillary electrophoresis is a rapidly developing method which could be used for therapeutic drug monitoring purposes after providing acceptable reproducibility and sensitivity. A method for analysis of ribociclib, letrozole and ibuprofen by capillary electrophoresis using ketoprofene as an internal standard was developed and validated. The separation was obtained with 75 mmol dm−3 phosphate, 8,5 mmol dm−3 sulphobutylether-β-cyclodextrin (SBE-β-CD) and 5% isopropanol. The hydrodynamic injection was performed at −50 mbar pressure for 5 seconds, after the injection of ultrapure water for 6 seconds. The method is precise, linear in a range of mass concentration of 1 to 75 µg cm−3, specific and robust for the change of temperature, SBE-β-CD concentration and voltage
Epistemological and didactic analysis of the notion of a polynomial
No full textPolinom kao jedan od najfundamentalnijih pojmova u gotovo svim područjima matematike, ima istaknutu ulogu u predtercijarnom i tercijarnom matematičkom obrazovanju. Upravo to ga kvalificira da bude idealan objekt institucijskog i epistemološkog istraživanja o didaktičkim procesima. Potreba za takvim istraživanjem inducirana je: 1. na globalnoj razini, malobrojnim istraživanjima u kojima je polinom glavni objekt istraživanja te neodgovorenim pitanjima o razlozima različitog načina definiranja pojma polinoma u predtercijarnom obrazovanju [13,221]; 2. na lokalnoj razini, recentnim promjenama u znanju za podučavanje u predtercijarnom obrazovanju i mogućim efektima tih promjena na tercijarno obrazovanje. Odabrani teorijski okvir, Antropološka teorija didaktike (ATD), nudi alate koji omogućavaju istraživanje epistemoloških i institucijskih aspekata znanja za podučavanje. Stoga se alatima ATD-a analizira tranzicija prema studiju matematike, kroz studij, kao i inverzna tranzicija, ona koju nastavnici matematike prolaze kada počinju podučavati matematiku u predtercijarnom obrazovanju. Dakle, analizira se dvostruki Kleinov prekid i tranzicija kroz studij matematike s obzirom na pojam polinoma. Pojam matematičke prakseologije koristi se za modeliranje i analiziranje matematičkih sadržaja i aktivnosti. Diseminacija matematičkih prakseologija analizira se i modelira pojmom didaktičke prakseologije. Didaktička transpozicija, koja je istodobno alat i metodologija, omogućava analiziranje znanja unutar obrazovnih institucija u odnosu na znanje discipline matematike. Prvo se analiziraju geneza i razvoj pojma polinoma u disciplini matematike, tj. razvoj znanja o pojmu polinoma koja epistemološki legitimiraju znanja koja se podučavaju u predtercijarnim i tercijarnim obrazovnim institucijama. Uzima se u obzir i reforma Nove matematike koja je inducirana promjenom u disciplini matematike. Posebno se istražuje realizacije reforme u hrvatskom gimnazijskom obrazovnom sustavu, kao i njeni rudimenti i mogući efekti na aktualni obrazovni sustav. Dokumenti koji propisuju znanje za podučavanje u hrvatskom predtercijarnom obrazovanju podvrgnuti su prakseološkoj analizi, kao i najkorišteniji gimnazijski udžbenici u zadnjih dvadesetak godina, kako bi se dobio uvid u sekundarno-tercijarnu tranziciju (prvi Kleinov prekid) od kad je uveden Bolonjski proces. S obzirom na pojam polinoma, analizira se obrazovanje matematičara i nastavnika matematike na Prirodoslovno-matematičkom fakultetu Sveučilišta u Splitu. Promatra se i mogući efekti drugog Kleinov prekida na buduće nastavnike matematike.The polynomial, as one of the most fundamental notions in almost all areas of mathematics, has a prominent role in pre-tertiary and tertiary mathematics education. That qualifies it to be an ideal object of institutional and epistemological research on didactic processes. The need for such research was induced by: 1. at the global level, the few studies in which the polynomial is the main object of research, and the unanswered questions about the reasons for the different ways of defining the notion of a polynomial in pre-tertiary education [13,221]; 2. at the local level, recent changes in knowledge for teaching in Croatian pre-tertiary mathematics education and the possible effects of these changes on university mathematics education. The selected theoretical framework, the Anthropological Theory of the Didactic (ATD), offers tools that enable the investigation of epistemological and institutional aspects of knowledge for teaching. Therefore, ATD tools are used to analyse the transition towards the study of mathematics, through the study, as well as the inverse transition, the one that mathematics teachers go through when they start teaching mathematics in pre-tertiary education. Thus, Klein’s double discontinuity, and transition through the study of mathematics, are analysed concerning the notion of a polynomial. A mathematical praxeology is a tool that is used for modelling and analysing mathematical contents and activities. The dissemination of mathematical praxeologies is analysed and modelled by the notion of a didactic praxeology. A didactic transposition, which is both a tool and a methodology, enables the analysis of knowledge within educational institutions concerning the knowledge of the discipline of mathematics. First, the genesis and development of the notion of a polynomial in the discipline of mathematics are analysed, i.e. the development of the knowledge about the notion of a polynomial that epistemologically legitimises the knowledge taught in pre-tertiary and tertiary educational institutions. The reform of New Mathematics, which was induced by a change in the discipline of mathematics, is also taken into account. The implementation of the reform in the Croatian high school education system is especially investigated, as well as its rudiments and possible effects on the current education system. Documents prescribing knowledge for teaching in Croatian pre-tertiary education were subjected to praxeological analysis, as well as the most used secondary textbooks in the last twenty years, as would gain an insight into the secondary-tertiary transition (Klein’s first discontinuity) since the Bologna process was introduced. The education of mathematicians and mathematics teachers at the Faculty of Science, University of Split is analysed considering the notion of a polynomial. The possible effects of Klein’s second discontinuity on prospective pre-tertiary mathematics teachers are also observed