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SEPARACIJA I SVOJSTVA EGZOSOMA IZ CEREBROSPINALNE TEKUĆINE BOLESNIKA S TRAUMATSKOM OZLJEDOM MOZGA
No full textObjectives: Severe traumatic brain injury (sTBI) is a complex, life-threatening
condition requiring emergent treatment with no known biomarkers to guide clinical
interventions. A promising source of such biomarkers are intracranial exosomes.
However, isolation of exosomes is still challenging with size exclusion chromatography
(SEC) emerging as a favourable tool to isolate total and intact exosomes. This study
aims to compare the efficiency of different SEC solutions for exosome isolation from
cerebrospinal fluid (CSF) of sTBI patients.
Patients and methods: Nine CSF samples from three patients requiring external CSF
drainage during the first three days post-sTBI were collected, pooled, and screened by
western blot for exosomal makers CD81 and CD9, lipoprotein markers apolipoprotein
AI (ApoAI) and E (ApoE), and albumin. The pooled sample was separated by four
gravity flow-based SECs with either a commercial prepacked column or an in-house
column packed with Sepharose CL-6B, Sephacryl S-400 or Superose 6 PG. A total of
46 fractions were collected per SEC and analysed by slot blot followed by Ponceau
staining. Immunodetection was performed on selected SEC fractions for albumin,
CD81, CD9, flotillin-1, ApoAI, and ApoE. Tunable resistive pulse sensing (TRPS) was
utilised for exosome size, concentration and surface charge measurement, while
transmission electron microscopy (TEM) was used for exosome visualisation.
Results: Post-sTBI CSFs contain exosomes, along with lipoproteins and albumin, as
shown by western blot, confirming the complexity of clinical samples. All four tested
SECs provided separation of exosomes but differed in efficiency. Sepharose CL-6B
SEC yielded the highest quantity of exosomes in TRPS measurement and resulted in
clear separation from lipoproteins and free proteins, as shown by exosome
visualisation by TEM and immunodetection of exosomal (CD9, CD81 and flotillin-1),
lipoprotein (ApoA1 and ApoE) and free protein (albumin) markers.
Conclusion: Intracranial CSF after sTBI has a complex composition encompassing
exosomes, lipoproteins and free proteins, which can be separated by SEC. However,
SEC designs vary and impact the exosome isolation efficiency. Sepharose CL-6B
stands out as an effective SEC resin to isolate exosomes from clinical samples.Cilj istraživanja: Teška traumatska ozljeda mozga (tTOM) je kompleksno životno
ugrožavajuće stanje koje zahtjeva hitno liječenje, ali nema poznatih biomarkera koji bi
pomogli u odlučivanju o kliničkim intervencijama. Intrakranijalni egzosomi predstavljaju
obećavajući izvor takvih biomarkera. Međutim, izolacija egzosoma je i dalje izazovna,
a kromatografija isključenjem po veličini (eng. Size Exclusion Chromatography, SEC)
pojavljuje se kao prikladan alat za izolaciju ukupnih i intaktnih egzosoma. Cilj ovog
istraživanja je usporediti učinkovitost različitih rješenja SEC-a za izolaciju egzosoma iz
CSF-a pacijenata s TBI.
Ispitanici i metode: Devet uzoraka CST-a od triju pacijenata kojima je uspostavljena
vanjska drenaža CST-a tijekom prva tri dana nakon tTOM-a prikupljeno je, objedinjeno
i ispitano western blot metodom na egzosomalne markere CD81 i CD9, lipoproteinske
markere apolipoprotein AI (ApoAI) i E (ApoE) te albumin. Skupni uzorak CST-a
odvojen je pomoću četiri metode SEC-a temeljene na gravitacijskom protoku, pomoću
komercijalne kolone za izolaciju egzosoma ili interno pakiranim kolonama napunjenim
punilima Sepharose CL-6B, Sephacryl S-400 i Superose 6 PG. Prilikom svake
separacije prikupljeno je ukupno 46 frakcija, nakon čega je uslijedila slot blot analiza i
bojanje Ponceau S. Imunodetekcija na odabranim frakcijama SEC-a provedena je na
albumin, CD81, CD9, flotillin-1, ApoAI i ApoE. Za mjerenje veličine, koncentracije i
površinskog naboja egzosoma korištena je metoda opažanja pomoću podesivog
otpornog pulsa (eng. Tunable Resistive Pulse Sensing, TRPS), dok je transmisijska
elektronska mikroskopija (TEM) korištena za vizualizaciju egzosoma.
Rezultati: CST nakon tTOM sadrži egzosome, lipoproteine i albumin, kao što je
prikazano western blotom, što govori u prilog kompleksnosti kliničkih uzoraka. Sve
četiri SEC metode omogućile su odvajanje egzosoma, ali su pritom pokazale različitu
učinkovitost. Prema mjerenjima pomoću TRPS, razdvajanje punilom Sepharose-CL
6B dovelo je do najvećeg prinosa egzosoma i rezultiralo jasnim odvajanjem od
lipoproteina i slobodnih proteina, kao što je prikazano vizualizacijom egzosoma
pomoću TEM-a i imunodetekcijom egzosoma (CD9, CD81 i Flotillin-1), lipoproteina
(ApoA1 i ApoE) i markera slobodnih proteina (albumin).
Zaključak: Intrakranijalni CST nakon tTOM složenog je sastava te sadrži egzosome,
lipoproteine i slobodne proteine, koji se mogu razdvojiti SEC-om. Međutim, dizajn SEC-a može značajno varirati i utjecati na učinkovitost izolacije egzosoma. Sepharose
CL-6B ističe se kao učinkovito punilo za kromatografsku izolaciju egzosoma iz kliničkih
uzoraka
The biochemical mechanisms of polysaccharide degradation in freshwater ecosystems
No full textSlatkovodni ekosustavi imaju ključnu ulogu u globalnom ciklusu ugljika, pri čemu bakterije razgrađuju polisaharide kroz mehanizme kolaboracije, oportunizma i sebičnosti. Utjecaj okolišnih čimbenika na strukturu mikrobnih zajednica istražen je prostorno-vremenskom analizom pomoću visoko protočnog sekvenciranja DNA. Mehanizmi razgradnje polisaharida praćeni su inkubacijama s fluorescentno označenim polisaharidima, dok su ključne bakterijske skupine identificirane kombinacijom sekvenciranja i fluorescencijske in situ hibridizacije. Sekvenciranjem metagenoma dodatno su otkriveni prostorno i sezonski specifični geni za razgrdanju ispitanih polisaharida. Rezultati su pokazali da mikrobne zajednice slatkovodnog povezanog ekosustava, unatoč sezonskim promjenama, zadržavaju stabilnost kroz temeljni središnji mikrobiom. Dokazana je i prisutnost sebičnog mehanizma razgradnje polisaharida, s varijacijama između jezera različitih trofičkih stanja i sezona. Bakterije iz koljena Bacteroidota, Planctomycetota, Proteobacteria i Verrucomicrobiota odgovorne su za razgradnju polisaharida. Ova disertacija produbljuje razumijevanje uloge mikrobnih zajednica u razgradnji polisaharida, ključnih za kruženje ugljika unutar slatkovodnih ekosustava.Freshwater ecosystems play a key role in the global carbon cycle, where bacteria degrade polysaccharides through sharing, scavenging and selfish mechanisms. Environmental influence on microbial community structures was investigated through spatiotemporal analysis using high-throughput DNA sequencing. Polysaccharide degradation mechanisms were tracked using fluorescently labelled polysaccharides incubations, while bacteria involved were identified through a combination of sequencing and fluorescence in situ hybridization. Metagenomic sequencing revealed spatially and seasonally specific genes responsible for the polysaccharide degradation. The results revealed stabile microbial communities in the freshwater network ecosystem through core microbiome, despite seasonal variations. Polysaccharide degradation thorough selfish mechanism among bacteria was proven, varying across lakes with different trophic states and seasons. Bacteria from the phyla Bacteroidota, Planctomycetota, Proteobacteria, and Verrucomicrobiota were identified as key polysaccharide degraders. This dissertation advances understanding of microbial role in polysaccharide degradation, an essential process for carbon cycling within freshwater ecosystem
Podatkovno vođena karakterizacija kinematike i snage hvatova za primjenu u rehabilitacijskoj robotici : doktorski rad
No full textThis thesis advances anthropomorphic soft robotic devices for hand rehabilitation in patients with neurological disorders, such as stroke and multiple sclerosis, focusing on restoring grasping capabilities needed for activities of daily living. The research
integrates three complementary methodological approaches. First, it establishes a real-time system for estimating and predicting grip force using surface electromyography. Using only one sensing position with optimized spectral masking and Koopman Operator Theory, the method achieves ∼5.5% error for grip force estimation and ∼17.9% for short-term predictions, with processing times of just 30ms, making it suitable for real-time adaptive assistance based on patient volition. Second, it develops simplified hand kinematic models by analyzing data from 77 participants performing 23 functional grasps. The approach identifies 116 highly correlated joint relationships, models them using regularized generalized linear and mixed-effects models, and clusters into 30 similar model groups. This reduces the degrees of freedom during grasping to 5 to 15 while maintaining high accuracy, offering a practical basis for designing rehabilitation devices with reduced complexity. Third, it details the design and fabrication of a 3D-printed soft robotic rehabilitation glove based on reduced hand kinematics. The innovative finger soft pneumatic actuator
combines cylindrical and ribbed geometries with a reinforcing element, creating an asymmetric bellows actuator validated through finite element method simulations and a modified pseudo-rigid-body model with positioning errors below 3.8mm.
These advances in EMG-based force feedback, sparse kinematic modeling, and soft actuator design constitute a comprehensive framework for developing effective hand rehabilitation devices.Ova disertacija doprinosi razvoju antropomorfnih mekih robotskih uređaja za rehabilitaciju šake kod pacijenata s neurološkim poremećajima, uključujući moždani udar i multiplu sklerozu, s ciljem učinkovitijeg obnavljanja sposobnosti hvatanja potrebne za svakodnevne aktivnosti (ADL). Rad integrira tri metodološka pristupa: predviđanje sile za povratnu vezu, reducirano kinematičko modeliranje i inovativni razvoj aktuatora. Prvi dio disertacije predstavlja novu metodu u stvarnom vremenu za procjenu i predviđanje sile stiska tijekom cilindričnog hvata korištenjem površinske elektromiografije (sEMG). Robotska rehabilitacija temeljena na EMG-u pokazala je poboljšanu funkcionalnu obnovu u usporedbi s konvencionalnim metodama terapije prisilno induciranog pokreta i tradicionalne fizikalne terapije. Metodologija omogućuje izravan pristup kontrolnoj varijabli—sili stiska—što omogućuje robotsku asistenciju koja se adaptivno prilagođava voljnom djelovanju pacijenta. Dok suvremene metode zahtijevaju više sEMG mjernih pozicija za točna predviđanja, predstavljena metoda postiže usporedive
rezultate koristeći samo jednu mjernu poziciju kroz optimiziranu spektralnu masku tijekom obrade signala i pristup temeljen na teoriji Koopmanovog operatora (KOT).Korištenjem naprednih tehnika transformacije podataka sa statičkim Koopmanovim
operatorom omogućuje se procjena trenutne sile stiska šake iz obrađenih EMG signala, dok se dinamički Koopmanov operator primjenjuje za kratkoročno predviđanje sile stiska na temelju tih procjena. Eksperimentalna validacija s 13 sudionika pokazala je robusnu izvedbu na dvije sEMG mjerne pozicije na podlaktici, bez značajne osjetljivosti na položaj elektroda. Metoda postiže ponderiranu srednju apsolutnu postotnu pogrešku (wMAPE) od približno 5.5% za procjenu sile stiska i 17.9% za kratkoročna predviđanja tijekom horizonta od 0.5s. Značajno je da algoritam obrađuje, procjenjuje i predviđa silu stiska unutar vremenskog prozora od 0.5s sEMG podataka u samo 30ms, što ga čini pogodnim za implementaciju u stvarnom vremenu u rehabilitacijskim uređajima. U drugom dijelu disertacije razvijaju se interpretabilni reducirani kinematički modeli hvatova šakom za rješavanje izazova prevelike složenosti prilikom konstrukcije rehabilitacijskih uređaja. Analizom najvećeg dostupnog skupa podataka o kinematici šake, s podacima od 77 sudionika koji izvode 23 funkcionalna hvata vezana uz ADL,
ovo istraživanje uvodi novi pristup za modeliranje međuzglobnih ovisnosti unutarprsta tijekom fleksije/ekstenzije (FE). Predložena metoda pojednostavljuje modeliranje uspostavljanjem izravnih zavisnosti između parova zglobova, identificirajući 116 visoko koreliranih odnosa koji su modelirani pomoću regulariziranih generaliziranih linearnih modela (GLM) u kombinaciji s ponderiranim linearnim modelima miješanih učinaka (LME). Hijerarhijsko grupiranje dodatno konsolidira ove odnose u 30 različitih klastera uz zadržavanje visoke točnosti. Ovaj sustavni pristup značajno smanjuje stupnjeve slobode (DOF) potrebne za modeliranje FE tijekom hvatanja na 5–15, nudeći praktičnu osnovu za razvoj protetičkih i rehabilitacijskih uređaja sa značajnim smanjenjem mehaničke i upravljačke složenosti. Treći dio disertacije predstavlja sveobuhvatan proces za konstruiranje, simulaciju i izradu 3D-tiskane meke robotske rehabilitacijske rukavice. Inovativni meki pneumatski aktuator za prst (SPA) razvijen je koristeći kinematička svojstva i radni prostor anatomskih prstiju kao konstrukcijsku osnovu. Aktuator integrira cilindričnu geometriju s rebrima i ojačavajućim elementom—debljom, manje rastezljivom strukturom—na donjoj strani, što rezultira asimetričnim cilindričnim aktuatorom s mjehovima pogonjenim pozitivnim tlakom. Dobiveni segmentirani kinematički modeli krutog tijela za aktuatore kažiprsta i malog prsta omogućuju precizno upravljanje pokretima. Simulacije metodom konačnih elemenata (FEM) pri različitim tlakovima između 0 to (numerical range) 3bar potvrdile su performanse aktuatora i njegovu usklađenost s putanjama ljudskog prsta. Za pojednostavljenje iterativnog procesa konstruiranja, uveden je modificirani model pseudo-krutog tijela (PRB), značajno smanjujući računalnu složenost uz zadržavanje odstupanja u pozicioniranju ispod 3.8mm u usporedbi s FEM simulacijama. Aktuatori su uspješno izrađeni korištenjem termoplastičnog poliuretana (TPU), a ergonomsko testiranje meke rukavice pokazalo je njenu funkcionalnost. Ova disertacija uvodi nove metode obrade EMG signala za povratnu vezu o sili, reducirane kinematičke modele hvatova i okvir za razvoj mekih robotskih aktuatora. Integracija ovih pristupa unaprjeđuje razvoj personaliziranih rehabilitacijskih uređaja za širok raspon funkcionalnih hvatova ključnih za svakodnevne aktivnosti
Spray drying of W/O emulsions for the preparation of polymeric microparticles
No full textUspostavljanje optimalnih reoloških svojstava i stabilnosti V/U emulzija tijekom tehnološkog procesa
sušenja raspršivanjem bitno je za postizanje željenih fizičko-kemijskih svojstava polimernih
mikročestica s uklopljenim lijekom. Cilj ovog istraživanja bio je ispitati mikrostrukturu, stabilnost i
reološka svojstva V/U emulzija s hidrofilnim lijekom vankomicin hidrokloridom u dispergiranoj fazi.
Kao strukturni polimer korišten je poli(D,L-laktid-ko-glikolid) (PLGA), a kao organsko otapalo
diklormetan. Formulacije su stabilizirane primjenom različitih stabilizatora, a mikrostruktura i stabilnost
emulzija ispitane su tehnikom nuklearne magnetske rezonancije niskog polja (LF-NMR), određivanjem
magnetskih relaksacijskih svojstava protona vodene faze. Reološka karakterizacija potvrdila je
pseudoplastično ponašanje emulzija, a primjenom reoloških modela određeni su parametri koji
kvantificiraju njihova svojstva pri uvjetima protoka. Modelirani su obrasci protoka emulzija kroz sustav
cijevi uređaja za sušenje raspršivanjem do komore za sušenje, uz definiranje profila brzine i smične
brzine ovisno o radijalnom položaju u cijevi, što je ključno za uvećanje mjerila procesa. Kvalitativni
sastav i mikrostruktura V/U emulzija pokazali su jasnu povezanost s veličinom čestica, morfologijom,
raspodjelom djelatne tvari unutar mikročestica te kinetikom oslobađanja vankomicina. Postignut je
visok sadržaj uklopljenog vankomicina i njegovo produljeno oslobađanje iz PLGA mikročestica.
Istraživanje predstavlja inovativni pristup karakterizaciji V/U emulzija kombinacijom magnetskih
relaksacijskih i reoloških metoda, postavljajući temelj za dizajn i optimizaciju robusnog procesa sušenja
raspršivanjem za proizvodnju polimernih mikročestica ujednačene kvalitete. Razumijevanje utjecaja
mikrostrukture i sastava emulzije na svojstva mikročestica od presudne je važnosti za razvoj naprednih
terapijskih sustava primjenom tehnologije sušenja raspršivanjem.Optimal rheological properties and stability under spray drying conditions are crucial for achieving the
desired physicochemical properties of the final dry product containing the drug. The aim of this study
was to investigate the microstructure, stability and rheological properties of W/O emulsions (water-inoil
emulsions) containing the hydrophilic drug vancomycin hydrochloride in the dispersed phase.
Poly(D,L-lactide-co-glycolide) (PLGA) was used as the structural polymer and dichloromethane as the
solvent for the continuous phase. The W/O compositions also contained various stabilizers. Low-field
magnetic resonance (LF-NMR) techniques were used to determine the magnetic relaxation properties
of the protons of the dispersed aqueous phase of each of the tested W/O emulsions. Based on these
properties, the droplet size and stability of the emulsions were determined. Rheological characterization
confirmed that the tested emulsions exhibited pseudoplastic properties. Numerical parameters important
for the description of emulsion properties under flow conditions were determined by applying the
appropriate rheological mathematical models. The flow pattern through the tubing system to the drying
chamber was determined. In addition, the profiles of average velocity and shear rate/shear stress were
defined as a function of radial position in the pipe. The qualitative composition and microstructure of
the W/O emulsions used in the spray drying process are related to the physicochemical properties of the
dry polymer particles obtained. All formulations showed high drug loading and prolonged release
profile. Different qualitative compositions and microstructures of the starting emulsions led to
significant differences in particle size, external morphology, drug distribution within the polymer matrix
and release rate. The study presents an approach to characterize W/O emulsions based on PLGA and
dichloromethane by a combination of magnetic relaxation and rheological properties, which provides
new insights into the microstructure and stability of the system. The described rheological numerical
parameters allow the determination of the dynamic similarity under different conditions. Understanding
how the W/O emulsion microstructure and the choice of stabilizers affect the physicochemical properties
of vancomycin-loaded microparticles is important for the design of robust spray drying process to
produce polymer microparticles and future research on these drug delivery systems
Ekstremna oborina na području Jadrana i Dinarida u simulacijama regionalnim klimatskim modelima
No full textThe coastal mountainous region of the eastern Adriatic and the Dinarides are Mediterranean hotspots for heavy precipitation events (HPEs), frequently causing severe damage. Despite considerable progress in the field, accurately representing HPEs across various time scales and projecting their future changes in regional climate models (RCMs) remains challenging. This study examines how model configuration affects extreme daily precipitation representation at climatological and event (HPEs) scales, alongside the impacts of spectral nudging and ocean atmosphere coupling. Med-CORDEX simulations of RCM CNRM-ALADIN and coupled CNRM-RCSM6 are analysed. Results show that advanced physical parameterisations of moist processes improve the intensity, frequency and extreme precipitation, particularly over the Dinarides, while improving the occurrence and structure of HPEs. However, challenges remain, such as underestimation of peak intensities and inconsistencies in vertical moisture distribution prior to HPEs. Spectral nudging improves the temporal variability at climatological scales and the occurrence and location of HPEs. The ocean-atmosphere coupling has a minor effect at the climatological scale during summer and autumn. However, it showed a more pronounced effect on spatial variability and precipitation structure during HPEs. These advancements in physical parameterisations help reduce uncertainties in future climate projections. The study examines climate change projections for mean and extreme precipitation until the late 21st century, utilising simulations from the EURO-CORDEX ensemble under three greenhouse gas concentration scenarios. Historical simulations capture spatial variability and seasonal variations but reveal wet biases in winter and autumn and dry biases in summer across the Dinarides. Projections indicate a shift in the mean precipitation regime, with winter precipitation increasing over northern lowlands, summer precipitation decreasing in southern regions and minimal changes in spring and autumn across the Dinarides. Extreme precipitation is projected to intensify and become more frequent in winter and autumn, especially in the lowlands, while summer shows greater uncertainty but suggests intensification within fewer events.Obalno i gorsko područje istočnog Jadrana i Dinarida jedna je od žarišnih točaka u Sredozemlju za događaje s obilnom oborinom (engl. heavy precipitation events, HPEs), koji često uzrokuju ozbiljne štete. Unatoč dosadašnjem napretku, precizno predstavljanje HPE-a na različitim vremenskim skalama i projekcije njihovih budućih promjena u simulacijama regionalnim klimatskim modelima (engl. regional climate models, RCMs) i dalje predstavljaju izazov. Ovo istraživanje ispituje kako konfiguracija modela utječe na simulacije ekstremnih dnevnih oborina na klimatološkim skalama i tijekom pojedinačnih događaja (HPEs), uz utjecaje spektralne prinude i združivanja atmosfere i oceana. Analizirane su Med-CORDEX simulacije RCM CNRM-ALADIN i združenog CNRM-RCSM6 modela. Rezultati pokazuju da unaprijeđene fizikalne parametrizacije mokrih procesa poboljšavaju simulaciju intenziteta oborine, učestalosti i oborinskih ekstrema, osobito nad Dinaridima, dok na razini pojedinačnih HPE-a, poboljšavaju njihovu pojavu i strukturu. Međutim, ostaje mjesta za poboljšanja, poput podcjenjivanja najintenzivnije oborine i odstupanja u vertikalnoj distribuciji vlage neposredno prije HPE-a. Primjena spektralne prinude poboljšava vremensku varijabilnost na klimatološkoj skali te pojavu i lokaciju HPE-a. Združivanje atmosfere i oceana ima manji učinak na klimatološkoj skali tijekom ljeta i jeseni. Međutim, pokazuje se izraženiji učinak na prostornu varijabilnost i strukturu oborine tijekom HPE-a. Ovaj napredak u fizikalnim parametrizacijama pomaže smanjiti nepouzdanosti u klimatskim projekcijama. Nadalje, istraživanje ispituje klimatske projekcije za procjenu promjena srednje i ekstremne oborine do kraja 21. stoljeća, koristeći simulacije iz EURO-CORDEX ansambla prema tri scenarija koncentracije stakleničkih plinova. Povijesne simulacije bilježe prostornu varijabilnost i sezonske varijacije, ali precjenjuju srednju oborinu zimi i u jesen, dok je ljeti podcjenjuju, osobito nad Dinaridima. Projekcije upućuju na promjenu režima prosječne oborine, s povećanjem tijekom zime u sjevernim nizinama, smanjenjem u južnim predjelima ljeti i minimalnim promjenama u proljeće i jesen nad Dinaridima. Očekuje se da će se ekstremne oborine intenzivirati i postati učestalije zimi i u jesen, osobito u nizinama, dok se uz veće nepouzdanosti ljeti također očekuje intenzifikacija tijekom manjeg broja događaja
Haptoglobin glycosylation in colorectal cancer
No full textKolorektalni karcinom drugi je uzročnik smrti među karcinomima kako u svijetu tako i u Hrvatskoj. Najčešće se javlja sporadično, ali može imati i nasljednu komponentu. Otkrivanje novih, specifičnijih, učinkovitijih i manje invazivnih biljega kolorektalnog karcinoma unaprijedilo bi dijagnostičke i prognostičke mogućnosti u kliničkoj praksi. Prethodna istraživanja pokazala su promjene u N-glikozilaciji proteina plazme u kolorektalnom karcinomu. Jedan od potencijalnih nositelja tih promjena je haptoglobin, protein akutne faze, koji ima četiri glikozilacijska mjesta u svojoj strukturi. U ovom doktorskom radu razvijene su analitičke metode za analizu glikozilacije haptoglobina iz seruma ili plazme velikog broja uzoraka na razini glikopeptida i ukupnih N-glikana. Primarno istraživanje napravljeno je na 185 uzoraka seruma ispitanika s kolorektalnim karcinomom i 185 kontrola prikupljenih u biobanci LUMC (engl. Leiden University Medical Center) u Nizozemskoj. Analiza je napravljena specifično za svako glikozilacijsko mjesto upotrebom spregnutog sustava tekućinske kromatografije sa spektrometrijom masa. Validacijsko istraživanje provedeno je na 224 uzorka plazme ispitanika s kolorektalnim karcinomom i 269 kontrola. Ovi uzorci su prikupljeni u Kliničkom bolničkom centru Sestre milosrdnice u Zagrebu u Hrvatskoj. Ukupni N-glikom haptoglobina analiziran je na uzorcima validacijskog istraživanja metodom tekućinske kromatografije ultravisoke djelotvornosti s fluorescentnom detekcijom. Primjenom metode logističke regresije ispitana je značajnost povezanosti promjena u glikozilaciji haptoglobina i stanja kolorektalnog karcinoma. Statistički značajne promjene uočene su u povećanoj razini manje razgranatih glikanskih struktura, ukupnoj fukozilaciji i sijalinizaciji. Iako su određene promjene specifične za glikozilacijsko mjesto, rezultati primarnog istraživanja potvrđeni su u validacijskom istraživanju. Promjene u fukozilaciji i sijalinizacji oslikavaju promjene prethodno objavljene na ukupnim proteinima plazme.Colorectal cancer is the second leading cause of cancer-related deaths both worldwide and in Croatia. It often occurs sporadically but can also have a hereditary component. The development of new, more specific, effective, and less invasive tools for colorectal cancer would enhance diagnostics and prognostics in clinical practice. Previously, alterations in the N-glycosylation of plasma proteins in colorectal cancer were reported. One potential carrier of these changes is haptoglobin, an acute-phase protein that has four N-glycosylation sites in its structure. In this doctoral thesis, we developed high-throughput analytical methods for site-specific haptoglobin glycosylation analysis and haptoglobin N-glycome analysis from serum or plasma samples. Method for site specific analysis was applied to the discovery cohort, consisting of 370 participants, 185 colorectal cancer patients and 185 controls. Samples were obtained from the biobank Leiden University Medical Center in the Netherlands. Furthermore, haptoglobin N-glycome analysis using UHPLC-FLR was performed on samples from the validation cohort. The validation included 224 plasma samples from colorectal cancer patients and 269 controls collected at the Sestre milosrdnice University Hospital Center in Zagreb, Croatia. Logistic regression was used to test for associations of glycopeptide and labeled N-glycans features with case-control status. Statistically significant changes were observed in increased levels of less branched glycan structures, total fucosylation, and sialylation. While certain changes were specific for the glycosylation site, the discovery cohort findings were replicated in the validation study. Changes in fucosylation and sialylation reflect alterations previously reported in total plasma N-glycome
The Lado Ensemble of folk dances and songs of Croatia as a part of the national and cultural identity
No full textAnsambl narodnih plesova i pjesama Hrvatske Lado je profesionalni folklorni ansambl osnovan 1949. godine sa zadaćom prikupljanja, umjetničke obrade i scenskog prikazivanja bogate hrvatske plesne i glazbene tradicije na visokoj izvedbenoj razini u zemlji i svijetu. Cilj ovog rada jest da se spoznajama i metodama humanističkih i društvenih disciplina kritički analizira i interpretira umjetničko djelovanje, značenje i uloga Ansambla Lado te da se potvrdi postavka da se identitet Ansambla oblikovao i mijenjao pod utjecajem umjetničkih politika, razvoja izvedbenih mogućnosti te društveno-političkih okolnosti u kojima je osnovan i u kojima je djelovao te da je od početka imao predznak nacionalnoga. Nastavljajući se na temeljnu postavku, razmotrit će se i mogućnost percipiranja Lada kao hrvatskoga kulturnog brenda. Zvonimir Ljevaković, jedan od idejnih utemeljitelja i dugogodišnji umjetnički ravnatelj Lada, od 1949. do 1974., dao je osnovnu odrednicu umjetničkog rada Ansambla koja se zasniva na težnji da se u izvedbi bude što bliže autentičnim tradicijskim oblicima istodobno poštujući specifičnosti lokalnoga stila. Nadalje, Lado je plesni folklorni ansambl koji se sustavno razvijao u vrhunski folklorni zbor, osposobljen za samostalne vokalne i vokalnoinstrumentalne koncerte, što je rijetkost u usporedbi sa sličnim ansamblima u svijetu. U Ansamblu kao samostalna izvedbena tijela djeluju Ladarice, muška vokalna skupina Vokalisti Lada i Orkestar Lada koji su svojim umjetničkim djelovanjem postali dio Ladova identiteta. Provedeno istraživanje Ladovih gostovanja u inozemstvu te analiza osvrta domaće i inozemne kritike potvrdilo je da je hrvatski profesionalni folklorni ansambl uvijek nailazio na oduševljenje široke publike i stručne kritike koja ga od samih početaka prepoznaje kao čuvara narodnog blaga i kulturnog ambasadora u svijetu. Zaključno može se reći da se Lado u više od sedam desetljeća bogatog, umjetničkog djelovanja izgradio u hrvatski kulturni brend koji domaća publika i mediji prepoznaju kao simbol nacionalnih vrijednosti, čuvara i promicatelja hrvatske tradicije u domovini i u svijetu.INTRODUCTION: Traditional culture as part of cultural heritage is an indispensable part of national identity. Previous research has shown that the conceptions of public presentation of folklore changed in accordance with the political and socio-historical context. From the beginning, under the influence of the Peasant Concord (educational organization of the Croatian Peasant Party), they were conceived as a way of shaping and preserving national consciousness. There are many written works on amateur folkloric activity, but scientific reviews of the work of the national professional Ensemble of Folk Dances and Songs of Croatia Lado are few so far (Zebec 2008, Vitez 2009, Sremac 2010, Niemčić 2014; 2016; 2024, Ćaleta 2024). The aim of this work is to critically analyze and interpret the artistic activity, meaning and role of the Lado Ensemble using the knowledge and methods of the humanities and social disciplines. As well, to confirm the assumption that Lado's own identity, being cultural and national, which was formed in the 75 years of its artistic activity, and its uniqueness compared to other national ensembles. The starting point is that the identity of the Lado Ensemble changed under the influence of artistic policies, the development of performance possibilities, and the socio-political circumstances in which it was founded and in which it has operated since its foundation. Since 1950, it has been obliged to perform the so-called Yugoslav program, and with the creation of an independent Croatian state, it now performs Croatian programs. Furthermore, reviews of the performances of the Lado Ensemble in the country and abroad are critically questioned, and the extent to which Lado managed to achieve a combination of traditional heritage and the contemporary life of stage art is analyzed: on the one hand, the performance aims to preserve traditional forms as much as possible with high artistic achievements, and on the other hand, to be market attractive. It also wants to show that the Lado Ensemble, with its recognizable artistic personality and consciously created identity, which is part of the national and cultural, and significant international activity, has the characteristics of a cultural brand.
RESEARCH STRATEGY AND METHODOLOGY: Following contemporary ethnographic practice, with a general tendency to create a specific multi-methodological strategy whose purpose is to understand the phenomenon in question (Relja 2009: 121), different research techniques and methods were used in the preparation of the work. During the four phases of the work: collection of material, analysis (qualitative, quantitative, and combined), interpretation and synthesis, analytical, synthetic, comparative, and descriptive methods were used. The text of the work was built by modeling contrasting views, by letting the author's voices of narrators into the scientific text (Čapo Žmegač, Gulin Zrnić and Šantek 2006). In terms of methodology, the work is based on conducted interviews and a survey, as well as on the analysis of the theoretical material of the humanities and social sciences important for the topic under discussion. Due to the lack of written sources about the Lado Ensemble, an extensive and demanding archival research was carried out, which used newspaper articles, concert programs and promotional materials from private archives, statistics of Lado's performances with performed programs, as well as data obtained from interviews with the artists of the Ensemble.
HISTORICAL DEVELOPMENT AND ARTISTIC POLICIES OF LADA: The Lado Ensemble was founded on November 11, 1949, by a decree of the Government of the People's Republic of Croatia with the task of presenting artistically processed folklore treasures and helping folklore groups in their artistic development. Zvonimir Ljevaković, the founder and long-time artistic director of the Lado Ensemble, from 1949 to 1974, gave the basic conception of the Ensemble's artistic work, which is based on the aspiration to be as close as possible to authentic traditional forms in performance while respecting the specificities of the local style. In order to understand Ljevaković's artistic conception, it is necessary to have an insight into the development of the stage presentation of folklore in Croatia, which was initially used for the purpose of shaping and awakening national consciousness (Sremac 2010). Namely, the Croatian Peasant Party and its educational organization Seljačka sloga, with a well-thought-out policy and organization of the festival, use folklore to confirm and emphasize national identity and develop national consciousness in a large part of the illiterate Croatian people. Sremac (2010) describes how the initiative for the establishment of national professional folklore ensembles came from the then Soviet Union, where Igor Mojsejev founded the famous ballet ensemble in 1937. This famous ballet dancer and choreographer is inspired by folklore, but in addition to ballet stage aesthetics, he puts skill and attractiveness in the foreground with elements of acrobatics. This way of presenting folklore was accepted in Eastern European countries, and ensembles from the eastern part of the former Yugoslavia were also prone to it. The national professional ensembles of the former Yugoslavia were created from already established amateur folklore groups, such as the Croatian ensemble was created from the folklore section of the Youth Cultural and Artistic Society (OKUD) "Joža Vlahović". In the first years of activity, along with Ljevaković, Ana Maletić, a dance pedagogue of contemporary dance, was appointed as the artistic director. However, she has a different idea of stage presentation of folklore, with which, due to stylization, she departs more from traditional templates, and due to the difference and disagreement in approach, she leaves the Ensemble (Đurinović 2008: 55-62). The famous composer of choral music Emil Cossetto also worked in the Ensemble, who with his arrangements and interpretations from the Kajkavian regions greatly contributed to the recognition of the Lado Ensemble's vocal expression. Ljevaković shapes his vast knowledge based on many years of field research of Croatian tradition, with exceptional skill, sensibility, and an artistic gift, into a stage presentation of folklore presented in the performances of Lada. Ensemble Lado is Ljevaković's vision of how the values of the Croatian tradition, "in which the spirit of the Croatian people is reflected", should be presented on stage, and therefore preserved from oblivion. Božo Potočnik (2009: 130) thus writes that Zvonimir Ljevaković is a folklore expert who decided to artistically convey the life force of the Croatian people on stage, using the language of folklore, music, and dance. Ljevaković's choreographic opus consists of about thirty choreographies (Ladarke, Prigorski dances, Posavski dances, Vrličko kolo, Krčki tanac, Dubrovnik kolo poskočica - Linđo, Drmeš etc.) and despite the changes in the artistic policies of his successors and the expansion of the program with new choreographic visions, forms the basis of the Lado Ensemble's artistic program. After more than two decades of artistic leadership of Lado, Ljevaković departs, but his artistic vision of performing folklore on stage has remained to this day. After Ljevaković, Ivan Ivančan (1974 – 1980) came to lead the Ensemble, who is also important for Lado as a choreographer (he is the author of about twenty choreographies in Lado's repertoire). Aware of Ljevaković's importance, Ivančan designs concerts whose backbone is Ljevaković's choreography, but Lada's dance repertoire begins to expand with new choreographies, he is the author of some of them, and for some he engages other folklore creators (Branko Šegović, Savo Popović, Mirko Ramovš, Stanimir Višinski etc.). It certainly brings variety to Lado’s program and thus opens a new page of Lado’s artistic activity. He also creates thematic concerts, which were a great step forward for those times, when the concept of dance folklore performances was based on the exchange of choreographies from different regions. He invites the distinguished pedagogue and choirmaster Dinko Fio to work daily on vocal technique and expand the Ensemble's musical repertoire. Also, an important point should be noted is his role in educational development. For example, he designes many educational concerts for school-age children. After the departure of Ivančan in 1980, Lado was without an artistic director for three years, and during that period the dance leaders, Ivan Šulina, Stjepan Poček and Ivica Dabac, work with the Ensemble and shape concert programs according to the experience and performance capabilities of Lado. Considering the activities of Lado during the time of Hanibal Dundović (1983 – 1991), we can say that there was a lack of great strides and folklore achievements in Lado, however, it was a period of stability. In his tenure, most of the new choreographies were signed by folklore creators: Vido Bagur, Karlo Mikačić, Dobrivoj Putnik, Branko Šegović, Vlado Šoć, Ivica Ivanković etc. It should be mentioned that Dundović created three choreographies for Lado. Also, Dundović accepted the initiatives of music directors Tomislav Uhlik (1983 – 1985) and Bojan Pogrmilović (1985 – 1998) for the increased activity of Lado as a concert ensemble, which improved the Ensemble's vocal potential. Analyzing the activities of Lado during the time of Ivančan Jr. (1992 - 2016), it can be said that it was a fruitful creative period. Lado’s repertoire has been enriched with about 40 new choreographies in the spirit of the "Zagreb school of folklore" (by Dr. Ivan Ivančan, Branko Šegović, Vidoslav Bagur, Miroslav Šilić, Ajša Ruždija, Milan and Goran Oreb, Andrija Ivančan, Vlado Šoć, Tomislav Miličević, Ivica Ivanković, Mojmir Golemac, Krunoslav Šokac, Valentina Šepak etc. Ivančan Jr. is the author of the choreography of the songs and dances of Međimurje Med Murom i Dravom. Furthermore, Ivančan Jr. designed and very successfully directed many thematic concerts and was also open to different musical and dance expressions inspired by folklore to attract a younger, non-folkloric audience (the first was the Lado Electro album by Hrvoje Crnić Boxer and Boris Harfman). The Ensemble's musical potential developed to unimagined heights. Until then, Lado, was known for singing related to the musical traditions of central and northern Croatia, and had mastered the stylistic features of the southern Croatian regions (thanks to the collaboration with Joško Ćaleta). Within Lado, the Orchestra, female vocal ensemble Ladrice and male vocal ensemble Lado’s Vocalists operate as independent performing bodies. The third point being that there is a collaboration between Lado and numerous collaborators, leading Croatian composers, arrangers, and ethnomusicologists, systematically researches and presents folk sacred traditions of the Lenten and Christmas cycle and Marian songs. Lado’s sacred repertoire was permanently enriched by: Božo Potočnik, Tomislav Uhlik, Marijan Makar, Joško Ćaleta, Dražen Kurilovčan, Ljubo Stipišić Delmata, Ivica Ivanković, Mihael Ferić, Branko Ivanković, Branko Starc. This laid the foundations of Lado's musical activity in the field of sacred music, which contributed to Lado growing into a top folk choir with high performance capabilities, which for the first time received awards usually reserved only for classical music performers. Ivančan Jr.’s role as artistic director during the four-year period (2016-2020), was followed by Andrija Ivančan, and Krunoslav Šokac. Given the brevity of their tenure and activity, during which there were no changes in Lado’s identity, we didn’t particularly look at the features of their artistic policies.
LADO AS A NATIONAL AND CULTURAL BRAND AND ITS IDENTITIES: The identity of the Lado Ensemble was shaped and changed under the influence of artistic policies, the development of performance possibilities, and the socio-political circumstances in which it was founded and in which it has operated since its foundation. From 1950 to 1989, depending on the politics of the time, it was obliged to perform the so-called the Yugoslav program, and since the creation of the independent Croatian state in 1991, only the Croatian program has been carried out (except for special thematic projects). Furthermore, research into the artistic activities of Lado confirmed that, regardless of the socio-political circumstances in which the Ensemble operated, the artistic leadership and members expressed a strong sense of national identity. Lado has always been recognized as an artistic ensemble that primarily cherishes the values of Croatian dance and music tradition, and thanks to its founder and first artistic director Zvonimir Ljevaković, it strives to be as close as possible to traditional forms. Furthermore, by analyzing the work, we confirmed that Ljevaković's artistic expression of high aesthetics with respect for local stylistic features is what makes Lado recognizable, and that Ljevaković's refinement and subtlety in the artistic representation of folklore is what separates Lado from other folklore ensembles. Ljevaković's conception continued to be applied and developed by his successors, and it has remained until today. At the same time, the Ensemble's performance abilities, especially musical ones, have developed. The analysis of artistic policy confirmed that Lado’s identity is cultural and national, which was formed during more than seven decades of artistic activity as an ensemble identity, unique in comparison to other ensembles. Identities are the starting point for showing the value of a brand, including Lado, and include all those features that show that, compared to other folklore ensembles, it is Lado that best fulfills the needs, expectations and wishes of the audience and that it means the greatest value to them. The brand's values are the brand's identities, and Lado's identities are: Lado - the "guardian" of the Croatian dance and music tradition; "2 in 1" - Lado is a superb dance folklore ensemble and a great folklore choir; Lado – "ambassador" of Croatia in the world; Lado – "traveling museum"; Lado – center for education on national intangible heritage; Lado – a successful symbiosis of tradition and modernity; Lado trademark – Posavina wheel. Independent performing bodies in the Ensemble, the female vocal ensemble Ladrice, the male vocal ensemble Lado’s Vocalists and the Orchestra, act as sub-brands, which have become part of Lado's identity. Today's Ladarice consists of the Lado female choir, which continued the work of the legendary nonet Ladarice, although with a completely different sound and program. Namely, Ladarice were not officially part of the Lado Ensemble until 2008, but with their artistic activity under the leadership of Božo Potočnik, they significantly influenced the popularity of traditional music and the popularity of Lado among a wide audience. The performing body of Lado is also the Orchestra, which consists of musicians who are mostly multi-instrumentalists and perform independent concerts, as well as Lado Vocalists who cherish the musical expression of Dalmatia.
COMPARISON OF CROATIAN FOLKLORE ENSEMBLE LADO WITH RUSSIAN ENSEMBLE IGOR MOJSEJEV AND IRISH RIVERDANCE ENSEMBLE: Comparing the performance of Lado with the spectacular performances of other well-known professional ensembles, we question whether Lado as a folklore ensemble, whose artistic expression is far from what is called a spectacle, can gain a greater presence on the world cultural market. We received a positive response from reviews by well-known American dance critics Heather Desaulniers and Anthony Shay. Desaulniers (2009) believes that spectacles like Riverdance and Lord of the Dance attract the audience like some television reality shows of dance competitions and expresses the opinion that attracting a mass audience is a success, but that these excessively produced performances leave a feeling of fakeness. He emphasizes that their technical excellence was indisputable and absolute, but what he remembers most about that evening was the artistic emptiness on stage. In the following, Heather Desaulniers positively comments on the performance of the Croatian ensemble Lado: "This past weekend, Music Center Strathmore proved that an evening of ethnic dance can be both technically great and deeply emotional. They hosted Lado, the Ensemble of Folk Dances and Songs of Croatia, which was generous and graceful in its performance and in which it honestly shared its customs and folk dances. Anthony Shay believes that Lado is a symbol of Croatian identity and says that Lado has an advantage over other national ensembles because it has retained the traditional values. "And the source has always been in the field, in the countryside. Ljevaković has always been my biggest role model. He respected the original folk dance, costumes, musical accompaniment much more than other choreographers. He managed to make art without being spectacular, and Lado respects that to this day" (Shay according to Derk 2008: 39).
LADO – AMBASSADOR OF CROATIAN CULTURE IN THE WORLD: From an exhaustive analysis of Lado’s foreign performances, the Croatian professional folklore ensemble performed on the world's most famous stages and that it always received the undisputed and indisputable enthusiasm of a wide audience and expert critics who recognized it as an ambassador of national culture from the very beginning. Considering the presented reviews, it is easy to read that what Lado conquers with, in addition to exceptional dancing and singing qualities and the perfect technique and musical skill of the Orchestra, is a display of folklore art that provides an experience of sincerity and conquers with purity of style and refinement. The comments and criticisms of the domestic and foreign press confirm that Lado is a top performer who does not resort to stylization and acrobatics to impress the audience, but, moreover, tries to present all the splendor, wealth, and exceptional diversity of the Croatian tradition, from folk costumes, dances, songs to customs, with the desire for the audience to feel the spirit of the Croatian people. Expert criticism recognizes the joy and emotion that Lado’s artists give to the audience. In addition to valuable recognitions, Lado was also awarded the INA award for the promotion of Croatian culture in the world for 2006, and the jury wrote in its explanation: "We can rightly say that Lado has been our ambassador in the world throughout its existence, promoting our cultural heritage at the highest level."
PUBLIC PERCEPTION OF THE LADO ENSEMBLE - SURVEY RESULTS: In order to examine the views more closely and empirically on the importance of the Lado Ensemble of Folk Dances and Songs of Croatia for national and cultural identity, a survey was conducted in 2002 using a Google form. In the descriptive part of the questionnaire, demographic characteristics such as gender, age, level of education, habits of attending Lado's concerts etc. were examined, while in the value section, the views on folklore in general, about the Lado Ensemble were examined (questions: "Do you consider yourself a Lado lover?", "Do you consider the Lado Ensemble important for the preservation of Croatian traditional values?", "Do you consider that Lado is an important part of the Croatian national identity?", "Do you consider that is the artistic activity of the Lado Ensemble important for Croatian culture?", "Do you consider the Lado Ensemble a Croatian cultural brand?"...),
Prijenos sila kroz zrnati materijal na pragu cikličke posmične deformacije
No full textZrnati materijal podvrgnut cikličkom opterećenju karakteriziraju promjene modula posmika, pornih tlakova i volumena. Do promjene dolazi kada amplituda cikličke posmične deformacije prijeđe određenu vrijednost tzv. prag cikličke posmične deformacije. Posljedice prelaska praga se odražavaju kao ciklički fenomeni: slijeganja, nagomilavanja pornih tlakova, ojačanja i degradacije čvrstoće.
Kako bi se istražili ciklički fenomeni potrebno je modelirati prijenos sila u sustavu zrna i šupljina, pijesku ovisno o amplitudi deformacije. Osnovni alat istraživanja je numerička metoda diskretnih elemenata. Pomoću trodimenzionalnog numeričkog modela simulira se laboratorijski pokus jednostavni direktni posmik. Numerički model sastoji se od velikog broja zrna (574 507 zrna), a kalibriran je na osnovu tri krivulje (krivulja redukcije, krivulja nagomilavanja pornih pritisaka vode, histerezna krivulja).
Izvlačenje i analiza podataka iz numeričkog modela odvija se na nekoliko razina. Na mikro razini dan je primjer određivanja stabilnosti jednoga lanca sile, definirani su pozadinski mehanizmi (kompresija, ekstenzija i fleksija), a određen je i dominantan kontrolni mehanizam (postepena translacija zrna). Na mezo razini provjereni su kriteriji za definiranje lanaca sile (srednja sila, kut između kontaktnih sila, duljina lanca sile, grananje lanca sile).
Lanci sile imaju ključnu ulogu kao mehanizam prijenosa sile u zrnatom materijalu i određuju mehanička svojstva materijala: stabilnost, elastičnost i protočnost. Više lanaca sile čini jaku mrežu, čija stabilnost, a time i stabilnost sustava je određena na osnovu promjene: broja lanaca sile, mehaničkog koordinatnog broja i raspodjele veličina kontaktnih sila. Način širenja poremećaja sustavom je određen grafičkom analizom konfiguracije lanaca sile ovisno o amplitudi i ciklusu. Za opis cikličkog ponašanja zrnatog materijala na makro razini predlažu se dva praga. Prag akumulacije γt = 4∙10-5 i prag stabilnosti γt = 3∙10-4.Granular material subjected to cyclic loading is characterized by the change of shear modulus, pore water pressure and volume. The change occurs when the amplitude of the cyclic shear strain exceeds a certain value, i.e. the cyclic threshold shear strain. The consequences of exceeding the threshold are reflected as cyclic phenomena: settlement, pore water pressure build-up, stiffening and degradation of stiffness.
In order to investigate cyclic phenomena, it is necessary to model the force transmission in the system of grains and voids (sand), depending on the strain amplitude. The basic research tool is the numerical discrete element method. Using a three-dimensional numerical model, the laboratory simple shear test was simulated. The numerical model consists of a large number of grains (574,507 grains), and is calibrated on the basis of three curves (reduction curve, pore water pressure accumulation, hysteresis loop).
Extraction and analysis of data from the numerical model takes place on several levels. At the micro level, an example of determining the stability of a single force chain is given, the underpinning mechanisms (compression, extension and flexion) are defined, and the dominant control mechanism (gradual grain translation) is also defined. At the meso level, the criteria for defining force chains were verified (mean force, angle between contact forces, length of force chain, branching of force chain).
Force chains play the key role as a force transfer mechanism in granular material and they determine the mechanical properties of the material: stability, elasticity and flow. Several force chains form a strong network, the stability of which, and thus the stability of the system, is determined based on changes in: the number of force chains, the mechanical coordinate number and the distribution of contact force sizes. The propagation mode of disturbances in the system is determined by graphical analysis of the configuration of force chains depending on the strain amplitude. Two thresholds are proposed to describe the cyclic behaviour of granular material at the macro level. Accumulation threshold γt = 4∙10-5 and stability threshold γt = 3∙10-4
Properties of homo- and heterometallic complexes prepared using tris(oxalato)chromate(III) and tris(oxalato)ferrate(III) building blocks with alkyl-ammonium cations
No full textReakcijama vodenih otopina građevnih blokova [M(C2O4)3]3– (M = Cr3+, Fe3+) koji sadrže katione (CH3)2(C2H5)NH+ odnosno (CH3)(C2H5)2NH+ s jednostavnim solima prijelaznih metala (Cu2+, Mn2+ ili Co2+) uz dodatak N-donorskih liganada priređena su 23 nova spoja s ugrađenim alkil-supstituiranim kationima. Izolirano je 13 heterometalnih (8 [MnIICrIII], 3 [CoIICrIII], 1 [MnIIFeII] i
1 [CoIIFeIII]) i 10 homometalnih (7 [CrIII], 2 [FeIII] i 1 [MnII]) spojeva, različite nuklearnosti i dimenzionalnosti. Svojstva priređenih sustava istraživana su IR- i UV/Vis-spektroskopijom, termičkom analizom, difrakcijom rendgenskih zraka u monokristalu i prahu, te mjerenjem magnetizacije. Električna svojstva odabranih spojeva su istražena impedancijskom spektroskopijom mjerenjem ovisnosti vodljivosti o relativnoj vlažnosti i temperaturi. Tri izabrana heterometalna spoja istražena su kao molekulski prekursori za dobivanje čistih faza oksida spinelne strukture termičkom razgradnjom u jednom koraku. Četiri spinelna oksida su dobivena pirolizom smjese dvaju ili triju oksalatnih kompleksa pomiješanih u odgovarajućem omjeru. Svim oksidima istražena su (mikro)strukturna i optička svojstva, te fotokatalitička aktivnost u razgradnji organskih bojila pod vidljivim zračenjem bez i uz dodatak H2O2, a odabranima magnetska i električna svojstva.By reacting aqueous solutions of the building blocks [M(C2O4)3]3– (M = Cr3+, Fe3+) containing cations (CH3)2(C2H5)NH+ or (CH3)(C2H5)2NH+ with simple salts of transition metals (Cu2+, Mn2+ or Co2+), with the addition of N-donor ligands, 23 new compounds with incorporated alkyl- substituted cations were prepared. 13 heterometallic (8 [MnIICrIII], 3 [CoIICrIII], 1 [MnIIFeII] and 1 [CoIIFeIII]) and 10 homometallic (7 [CrIII], 2 [FeIII] and 1 [MnII]) compounds with different nuclearity and dimensionality were isolated. The properties of the prepared compounds were investigated by IR and UV/Vis spectroscopy, thermal analysis, single-crystal and powder X-ray diffraction and magnetization measurements. The electrical properties of selected compouns were investigated using impedance spectroscopy by measuring the dependence of conductivity on relative humidity and temperature. Three selected heterometallic compounds were investigated as molecular precursors for the preparation of pure oxide phases with spinel structure by thermal decomposition in one step. Four spinel oxides were obtained by pyrolysis of a mixture of two or three oxalate complexes in a suitable ratio. The (micro)structural, optical and photocatalytic properties in the degradation of the organic dyes under visible irradiation without and with addition of H2O2 were investigated for all oxides, as well as the magnetic and electrical properties for selected oxides
Illuminations of the manuscript of Hatifi's Tīmūrnāma in Croatian Academy of Sciences and Arts (HAZU) in Zagreb
No full textEpska poema Tīmūrnāma (Knjiga o Tīmūru) perzijskog pjesnika ‘Abdullāha Hātifīja (oko 1416. - 1520.), u islamskom se svijetu ubraja u red najpopularnijih stihovnih povijesnih kronika na perzijskom jeziku. Napisana je između 1492. i 1498., na poticaj Badī‘ al-zamāna Mīrze (umro 1514.), u vrijeme vladavine njegova oca Sultana Ḥusayna Bāyqare, posljednjeg vladara Timuridske dinastije. Posvećena je velikom ratniku, osvajaču i zaštitniku umjetnosti Tīmūru (oko 1336. – 1405.), osnivaču Timuridskoga Carstva i obnovitelju mongolskog poretka, koji je pokorio golema prostranstva od Indije do Sredozemlja. Premda veliča osvajačke pothvate i vladavinu rodonačelnika suparničke dinastije, najveći broj prepisanih i oslikanih rukopisa Tīmūrnāme nastao je pod Safavidima, iranske vladarske dinastije u periodu od 1501. do 1736. U Orijentalnoj zbirci Arhiva Hrvatske akademije znanosti i umjetnosti u Zagrebu, pod signaturom OZHA R 754, sačuvan je iluminirani prijepis ovog značajnoga djela, oslikan s do danas sačuvanih šest minijatura, rukom nepoznata safavidskoga sitnoslikara. Iznimno važan s više aspekata, rukopis zagrebačke Tīmūrnāme do sada nije bio predmetom sveobuhvatne kritičke povijesnoumjetničke obrade. Riječ je o rukopisu čiji nastanak nije nužno povezan s narudžbom nekog uglednika ili vladara, već je izrađen kao knjižni proizvod za potencijalnog kupca iz krugova imućnije obrazovane klijentele toga vremena. Njegove minijature odražavaju temeljne stilske i ikonografske karakteristike iluminiranih rukopisa kronika u stihovima iz Širaza XVI. stoljeća, nastalih u radionicama koje su stvarale za širu publiku. U sklopu kodikološke obrade čitavoga rukopisa, posebna se pažnja posvećuje analizi i interpretaciji njegove likovne opreme. Minijature, koje sa stajališta povijesti umjetnosti i kulture zaslužuju osobitu pozornost, predmetom su formalne, stilske i ikonografske analize. U radu se temeljem komparativnih spoznaja podrobno analizira njihov odnos prema tekstu, moguće podrijetlo njihova stila i njihovo mjesto u povijesnom i kulturološkom kontekstu perzijske minijature. Dosadašnji podatci o rukopisu i njegovom nastanku kritički su revidirani i stavljeni u kontekst novijih internacionalnih saznanja.The epic poem Tīmūrnāma (A Book on Tīmūr) by Persian poet 'Abdullāh Hātifī (ca 1416 – 1520) counts among the more popular Persian chronicles in verse composed in the Islamic world. Commissioned by Badī' al-zamān Mīrza (d. 1514) during the reign of his father Ḥusayn Bāyqara, who was the last ruler of the Timurid dynasty, the Tīmūrnāma was composed between 1492 and 1498. It is dedicated to the great warrior, conqueror, and arts patron Tīmūr (ca 1336 – 1405), who, in an attempt to establish the Mongol order anew, conquered vast swaths of territory in the eastern Muslim world from the Indian Subcontinent to the Mediterranean, and thus laid the foundations for the establishment of a new, Timurid dynasty. Although written to exalt the exploits and rule of the founder of a rival dynasty, the largest number of copied and illuminated manuscripts of the Tīmūrnāma came down from the time of Safavids, an Iranian dynasty that ruled between 1501 and 1736. The Oriental Archive of the Croatian Academy of Sciences and Arts in Zagreb holds one illuminated manuscript of the Tīmūrnāma (call number OZHA R 754) with six hitherto preserved miniatures that are the subject matter of this doctoral dissertation. The Zagrebian manuscript of the Tīmūrnāma is intriguing from several aspects; from the viewpoint of art, history, and culture, the fascinating element of this copy is doubtless its miniatures and their stylistic, i.e., iconographic characteristics. From the vintage of codicology and textual criticism, one interesting aspect of the Zagrebian manuscript is certainly numerous lacunae, the loci of their occurrence, and the nature of the present textual deficiency. The provenance of the Zagreb manuscript is a tough challenge for researchers. Even though it is reasonable to assume that the preserved six miniatures are not the final count of the original manuscript illumination, this manuscript of the Tīmūrnāma represents a noteworthy example of the miniature painting cycle depicting scenes from Tīmūr's life and his military and diplomatic campaign. In this study, methods of stylistic, iconographic, and codicological analysis were deployed in order to elaborate on the miniature painting and overall artistic (calligraphic) features of the Zagrebian manuscript of the Tīmūrnāma. Following the same methodology, a comprehensive comparative study of available manuscripts was conducted to clarify the circumstances and possible timeline of the miniatures' composition. The method of stylistic analysis focused on formal features of the miniatures enables us to contextualize the work more precisely in a historical and stylistic sense, while iconographic analysis facilitates a more precise definition of scenes and a better understanding of their relations with the literary contents of the work. Codicological analysis widens the framework for the study of visual elements of the work, facilitating thus better underpinning of their functionality in the totality of the literary corpus. As regards the inner structure of this study, an introduction brings a survey of the subject matter and topic of the research, with a focus on the beginnings of Persian miniature in general and the tradition of illuminating historical chronicles, as well as an overview of 'Abdullāh Hātifī's life and literary works. A detailed description of the Zagrebian manuscript of the Tīmūrnāma is then given, followed by an overview of the existing studies and reviews of the manuscript from the Croatian Academy of Sciences and Arts. Researchers such as Aleksej Olesnicki, Zagorka Janc, Muhamed Ždralović, Zlatko Karač, and especially and more thoroughly Tatjana Paić-Vukić were to thank for the introduction and presentation of the manuscript to the academic and general readership up today. A second thematic bloc comprises a chapter entitled "Styles and Schools of Persian Miniature in the XVI Century". The miniatures of the Zagrebian manuscript of the Tīmūrnāma cannot be properly comprehended without an insight into the stylistic and iconographic features of the book illumination under the Safavids in the XVI century. Henceforth, an overview of the era's significant painting schools and styles is given based on recent scholarly literature. Firstly, schools of the East, with the inevitable focus on Tīmūr's successors and the school of Herat, were introduced with remarks on the influence of this school in the XVI century. Then, the school of Bukhara, and the overall miniature painting tradition of the Transoxiana are introduced. The school of Tabriz is reviewed both during the reign of Šāh Ismā‘īl, the effective founder of the Safavid dynasty and later during the reign of his successor Šāh Ṭahmāsp. A survey of the school of Shiraz ensued with a particular focus on an illuminated exemplar of the Ẓafarnāma in the XVI-century Shiraz. In light of remarkable similarities between Šaraf al-dīn' Alī Yazdī's Ẓafarnāma and 'Abdullāh Hātifī's Tīmūrnāma, particularly observable in the titles of chapters, a study of Yazdī's poem, its meaning, illumination, and reception are of great interest for the study of Hātifī's work. The central chapter of this dissertation, entitled "Illuminations of the Manuscript of Hātifī's Tīmūrnāma from the Croatian Academy of Sciences and Arts," brings about a detailed analysis of the preserved miniatures. A thorough description of all the miniatures within the composition of their relevant folia and chapters is given, followed by a comprehensive analysis of each miniature and its characteristics. The first miniature is placed in the eighth chapter entitled Nishatsan-i sahibqiran dar shahr-i Balkh bar takht-i bulandpaye-yi khani va sar afrakhtan az afsar-i saltanat va jihanbani (Sitting of the Auspicious Ruler on the glorious throne of Khanate in the city of Balkh and Assuming the Position of Ruling and World Ordering). The scene depicts Tīmūr, who quashed his opponents and was trumpeted as the savior who would unite all the subjects under his banner and deploy them in the service of a world empire. A second miniature is painted in the eleventh chapter, the most illuminated chapter is the existing manuscripts of the Tīmūrnāma. The chapter is entitled Bazm arastan-i musnad nashin-i saltanat va jihanbani jihat-i kam yaftan-i shahzade-yi Jihangir az tharama-yi shajara-yi nakhlistan-i khani (Setting up a public celebration by the Occupant of the throne of world ruling and ordering to delight Prince Ğihāngīr, an offspring from a tree in the Palm grove of Khanate). The chapter narrates the story of the marriage of Tīmūr's eldest son, Ğihāngīr, to a princess from the ruling house of Choresmia. The miniature depicts Tīmūr's envoys in the audience of Yūsuf Ṣūfī of Choresmia. A third miniature comes in the fifteenth chapter entitled Tavajjuh namudan-i an sarvar-i sarafraz bi janib-i Dar al-saltana Shiraz (Turning of that Glorious Leader towards the royal capital of Shiraz), which narrates Tīmūr's sack of Shiraz. The miniature portrays the peaceful surrender of Shiraz, in which representatives of the Muzaffarid dynasty hand over the city keys to Tīmūr and his army. A fourth miniature is part of the twentieth chapter entitled Lashkar arastan-i sahibqiran bi qasd-i Shah Mansur va koshta shudan-i an gardankash (Equipping a Campaign by the Auspicious Leader against Šāh Manṣūr and the ruin of that ruffian). The miniature depicts Tīmūr in splendid attire and a Safavid taj upon his head while killing a lion with his bare hands, a personification of Šāh Manṣūr. A fifth miniature comes in the twenty-fifth chapter entitled Sipah asrastan-i sahibqiran bi nubet-i duvvum az sarhadd-i zulumat bi jang-i Tuqtamish Khan va' anan taftan-i Khan az an mamlikat-i jansitan (Equipping an Army by the Auspicious Leader for the second campaign against Tuqtamiš-ḫān at the frontiers of darkness and the Khan's swift departure from that Perilous region). The miniature portrays taking prisoners from the enemy ranks and their submission to Tīmūr as slaves. The last sixth miniature comes in the thirty-ninth chapter with short title Name navashtan-i sahibqiran bi qayser-i Rum (The Auspicious Leader writes a letter to the Kaiser of Rum). From the context of the relevant chapter and the surrounding verses that narrate the dispatch of emissaries, it could be concluded that the miniature depicts Bayazīd's envoy to Tīmūr. The concluding, most voluminous thematic unit of this study is reserved for a chapter entitled "The Zagrebian Tīmūrnāma – A Comparative Analysis" that comprises of comprehensive comparison of sixteen XVI century illuminated manuscripts of Hātifī's poem that were available for review. The principal aim of the comparison of available illuminated manuscripts of the poem was an attempt to find textual basis and an interpretative key for the miniatures in the Zagrebian manuscript with regard to their positioning within the text of the poem. I sought to ascertain whether there were any common textual stimuli for illumination of the Tīmūrnāma that could stem from some canonical prototype or model. Apart from that, I tried to address an intriguing question of whether there existed sets of illuminated manuscripts with common and shared characteristics or not, in which case the sequence of miniatures would be proved to be entirely arbitrary and on the whim of a manuscript's redactor, commissioner, copyist or miniaturist. I likewise strove to determine to what extent and in what way the Zagrebian manuscript fits within the known class of illuminated copies of the Tīmūrnāma in light of its miniatures' positioning with the text and possible interferences from [the presupposed] canonical model. The manuscripts that were consulted in the comparative preview were the following: [Hātifī, ‘Abdullāh], Tīmūrnāma, National Library St. Cyrill and Methodius in Sofia, Bulgaria OP 994; [Hātifī, ‘Abdullāh], Tīmūrnāma, British Library Or. 2838; [Hātifī, ‘Abdullāh], Tīmūrnāma, Topkapı Sarayı Müzesi Kütüphanesi H.1594; [Hātifī, ‘Abdullāh], Tīmūrnāma, Cambridge University Library Add. 1109; [Hātifī, ‘Abdullāh], Tīmūrnāma, Harvard Art Museums 1957.140; [Hātifī, ‘Abdullāh], Tīmūrnāma, Bibliothèque nationale de France Supplément persan 641; [Hātifī, ‘Abdullāh], Tīmūrnāma, The Walters Art Museum W.648; [Hātifī, ‘Abdullāh], Tīmūrnāma, Topkapı Sarayı Müzesi Kütüphanesi H. 1593; [Hātifī, ‘Abdullāh], Tīmūrnāma, Cambridge University Library King's Pote 85; [Hātifī, ‘Abdullāh], Tīmūrnāma, Sotheby's LOT 140; [Hātifī, ‘Abdullāh], Tīmūrnāma, Bodleian Library Elliott 403; [Hātifī, ‘Abdullāh], Tīmūrnāma, Topkapı Sarayı Müzesi Kütüphanesi R. 1591; [Hātifī, ‘Abdullāh], Tīmūrnāma, The Free Library Lewis O. 43; [Hātifī, ‘Abdullāh], Tīmūrnāma, British Library Add. 7780; [Hātifī, ‘Abdullāh], Tīmūrnāma, British Library Add. 22703; [Hātifī, ‘Abdullāh], Tīmūrnāma, Harvard Art Museums 2014.392. The conducted comparison of the Zagrebian manuscript with the sixteen illuminated manuscripts from the XVI century resulted in several important insights and conclusions pointing to significant overlapping and similarity, as well as specificity of the Zagrebian copy of the work. The results also show what iconographic features characterize the Zagrebian manuscript and set it apart from the rest of the illuminated class, expanding the repertoire of standard scenes for painting. Based on the outcomes of the comparison, it also became apparent that some miniatures that regularly appear in other copies were absent from the Zagrebian manuscript, which could indicate that some miniatures were extracted from the codex with parts of the poem's text. That leaves the Zagrebian manuscript as an incomplete yet significant representative of the tradition of the Tīmūrnāma's illumination from the XVI century. Its miniatures, mainly those unique in tradition in terms of the scenes they depict, offer a new insight into the illuminated narrative accompanying the poem's text. Finally, the study of the miniatures in the Zagrebian manuscript of the Tīmūrnāma contributes to a better understanding of the rich mosaic of Persian miniature painting in the XVI century. It is not possible to give a conclusive answer to the question of when, where, and why since its composition to the acquisition of the manuscript for the Croatian Academy of Sciences and Arts, the Zagrebian manuscript lost large parts of its text. At the same time, the remaining corpus was shifted back and forth haphazardly. Much like the question of the manuscript's ultimate provenance – all that remains to be studied further. Even though the text has numerous lacunae and no logical organization of the salvaged parts, the sequence of the miniatures tallies well with the historical chronology of Tīmūr's conquests and the main events of his life and career. The approximative date and location of the composition of the Zagrebian Tīmūrnāma are given based on the analysis of its six miniatures. Seemingly insignificant iconographic detail, a specific headgear worn by some characters in the miniatures points to the possibility that the manuscript was copied and illuminated sometime around the first half or the middle of the XVI century, i.e., in the early Safavid period. Stylistic features of the miniatures point to the hand of one and the same miniaturist. Drawing and painting characteristics observable in the studied manuscript point to Shiraz, the focal point of a refined artistic production of Safavid Iran, as the most likely location of its composition and illumination