Barokno slikarstvo u samostanima i rimokatoličkim crkvama u Vojvodini: doktorska disertacija

Disertacija je obranjena 6. travnja 2014. godine na Filozofskom fakultetu Sveučilišta u Zagrebu

Barokno slikarstvo u samostanima i rimokatoličkim crkvama u Vojvodini: doktorska disertacija

Disertacija je obranjena 6. travnja 2014. godine na Filozofskom fakultetu Sveučilišta u Zagrebu

Sadržaj teških metala u odabranim đubrivima koja su u upotrebi u Srbiji

Levels of heavy metals Cd, Cr, Ni and Pb obtained by analysis of inorganic and organic fertilizers available on the Serbian market are discussed in this paper. The first estimation of the heavy metal input in soils due to use of phosphate fertilizers is also given. The heavy metal contents of all analysed inorganic fertilizers were below the MAC according to the current Serbian regulations. Elevated concentrations of Ni were detected in two and a high Cr concentration in one sample of the substrates. The average (theoretical) heavy metal input in Serbian soils was calculated based on the application of 20 kg ha-1 P2O5 per year. The calculated heavy metal input was lower than European average and it is similar to the inputs recorded in Finland and Denmark.U radu su prikazani rezultati analize sadržaja teških metala Cd, Cr, Ni i Pb u uzorcima neorganskih i organskih đubriva koja se nalaze na tržištu u Srbiji, a data je i početna procena količine teških metala koja se unose u zemljište prilikom upotrebe fosfatnih đubriva. Sadržaj teških metala u svim analiziranim neorganskim đubrivima je ispod MDK po važećem Pravilniku, a u uzorcima supstrata, koji se svrstavaju u organska đubriva, izmerena je povišena koncetracija Ni (2 uzorka) i Cr (1 uzorak). Prosečan (teorijski) unos teških metala u zemljište u Srbiji pod pretpostavkom da se godišnje po hektaru primeni 20 kg P2O5 niži je od evropskog proseka i blizak je podacima za Finsku i Dansku

Supplementary data for the article: Mrđan, G. S.; Vastag, G. G.; Škorić, D. Đ.; Radanović, M. M.; Verbić, T. Ž.; Milčić, M. K.; Stojiljković, I. N.; Marković, O. S.; Matijević, B. M. Synthesis, Physicochemical Characterization, and TD–DFT Calculations of Monothiocarbohydrazone Derivatives. Structural Chemistry 2021, 32 (3), 1231–1245. https://doi.org/10.1007/s11224-020-01700-y.

Supplementary material for: [https://doi.org/10.1007/s11224-020-01700-y]Related to published version: [https://cherry.chem.bg.ac.rs/handle/123456789/4453

Valence framing of political preferences and resistance to persuasion

U ovom istraživanju testirali smo efekat takozvane valentne formulacije, koji podrazumeva da su stavovi formulisani u negativnom pravcu (kao suprotstavljanje nepreferiranoj alternativi) otporniji na kasnije pokušaje ubeđivanja. Teorijske osnove rada čine dva relativno nezavisna pravca proučavanja kognitivnih procesa: istraživanje procesa promene stavova i otpornosti na promenu s jedne strane i proučavanje procesa odlučivanja s druge. Dosadašnja istraživanja otpornosti stavova na promenu ukazuju na to da se negativni stavovi brže formiraju i teže menjaju. Postoje podaci i o tome da se negativne informacije pažljivije obrađuju i da im se daje veća težina u memoriji. Ova asimetrija u korist negativnih stavova nazvana je "efekat negativnosti". U okviru izučavanja procesa odlučivanja, s druge strane, otkriven je takozvani efekat formulacije (framing efect), koji ukazuje na pojavu da ljudi donose različite odluke o ekvivalentnim ali različito formulisanim alternativa-ma. U zavisnosti od toga da li je isti ishod formulisan kao dobitak ili gubitak, ljudi će birati ili odbacivati taj ishod. Postoje tri tipa valentne formulacije: formulacija rizičnih ishoda (efekat se formuliše kao dobitak ili gubitak), formulacija cilja (ističe se pozitivna posledica izvođenja radnje ili negativna posledica njenog neizvođenja), i formulacija atributa (ključno svojstvo opisuje se u negativnim ili pozitivnim terminima). Naša namera bila je da u eksperimentu ujedinimo ove dve oblasti i proverimo efekat uokviravanja na otpornost stava u situaciji izbora između dva politička kandidata. Ispitanicima smo davali informacije o dva objekta na osnovu kojih su oni razvili preferencije ka jednom od njih. U tu svrhu koristili smo tekstove dužine oko 700 reči, u formi članaka iz novina, u kojima su opisani kandidati i njihovi programi, tako da se vrlo jasno uočavaju razlike među njima. Jedan kandidat je predstavljen kao politički konzervativac, političar desne orijentacije, dok je drugi opisan kao liberal- demokrata, orijentacije ka levom centru. Preliminarno testiranje pokazalo je da ispitanici vrlo dobro razlikuju ova dva programa (nije bilo ni jednog slučaja preklapanja). U samom ogledu učestvovalo je 120 ispitanika, studenata psihologije na Beogradskom univerzitetu. Nakon prezentacije tekstova, vršili smo manipulaciju kojom je polovina ispitanika navedena da o preferiranom kandidatu razmišlja u terminima podrške tom kandidatu, a druga polovina u terminima suprotstavljanja nepreferiranom kandidatu. Obe grupe su zatim izložene osporavajućoj poruci (u kojoj se ozbiljno narušava kredibilitet odabranog kandidata). Pokazalo se da su ispitanici koji su bili navedeni da o preferiranom objektu razmišljaju u terminima suprotstavljanja otporniji na kontrastavske argumente. Oni ispitanici koji su birali A (B) putem protivljenja B (A) u manjoj meri su promenili stav (M=1.26, SD=1.69) od ispitanika koji su bili upućeni na to da svoje stavove formulišu pozitivno, tj. kao podršku A (B) (M=3.61, SD=2.59). ANOVA je pokazala da je ova razlika značajna (F=14.169, p lt .001). Efekat faktora "kandidat" nije se pokazao značajnim, kao ni interakcija između faktora - nije se javila sistematska razlika u otpornosti između onih koji biraju A i onih koji biraju B. Drugim rečima, osporavajuće poruke imale su ujednačeno dejstvo na ove dve grupe. U našem ogledu je još jednom empirijski potvrđen efekat valentnog uokviravanja, čije se poreklo najčešće traži u adaptivnim mehanizmima: tvrdi se da, zbog toga što negativna informacija može biti signal za postojanje nesklada između očekivanog i postojećeg stanja ili znak nepovoljnih ili pretećih događaja, kod ljudi postoji tendencija da se značajno više kognitivno angažuju i promišljenije analiziraju situaciju. Suprotno tome, kada je informacija pozitivna, ljudi su skloni manje pažljivom i manje sistematskom procesiranju informacija. Za kasniju veću otpornost tako formiranih stavova objašnjenje nude takozvani "dualni modeli" promene stavova. Po njima je reč o dvofaznom procesu, u kojem ljudi (a) prvo opažaju negativne informacije na značajno drugačiji način, a zatim usled toga, (b) na različite načine procesiraju kontrastavske argumente. U našem ogledu to bi značilo da ispitanici upitani "da li su protiv nekoga" ulažu više kognitivne energije da prepoznaju i formulišu razloge protiv, u poređenju sa ispitanicima koji treba da reše "da li su za nekoga". Prva grupa, nazvaćemo ih "oponenti", stiče izgrađeniju bazu stava koja je onda spremnija da se suprotstavi izazivačkom argumentu. Ovi nalazi imaju značajne implikacije u političkoj komunikaciji. Ukazuju na to da je podrška nekom kandidatu ili političkoj opciji znatno nestabilnija nego što se to obično misli; da ljudi odlučuju vodeći se pre svega negativnim, a ne pozitivnim informacijama i da veoma fine varijacije u formi poruka značajno modeliraju njihov efekat, a shodno tome i konačni politički izbor.This study tested the "valence framing effect": an assumption that negatively conceptualized attitudes (as opposing the non-preferred alternative) are more resistant to later persuasion attempts. In the experiment we created choice between two political candidates and experimental subjects were led to conceptualize their political preferences in one of two possible ways: either as supporting the preferred candidate or as opposing the non-preferred candidate. The data indicate that negative preferences show less overall change when exposed to counterarguments. This finding can be incorporated in two theoretical frameworks: dual process theories of attitude change (Elaboration likelihood model) and descriptive decision making theories (Prospect theory). Results are discussed for their implications for the efficacy of political communication

Valence framing of political preferences and resistance to persuasion

This study tested the "valence framing effect": an assumption that negatively conceptualized attitudes (as opposing the non-preferred alternative) are more resistant to later persuasion attempts. In the experiment we created choice between two political candidates and experimental subjects were led to conceptualize their political preferences in one of two possible ways: either as supporting the preferred candidate or as opposing the non-preferred candidate. The data indicate that negative preferences show less overall change when exposed to counterarguments. This finding can be incorporated in two theoretical frameworks: dual process theories of attitude change (Elaboration likelihood model) and descriptive decision making theories (Prospect theory). Results are discussed for their implications for the efficacy of political communication.

VALENCE FRAMING OF POLITICAL PREFERENCES AND RESISTANCE TO PERSUASION 1

This study tested the "valence framing effect": an assumption that negatively conceptualized attitudes (as opposing the non-preferred alternative) are more resistant to later persuasion attempts. In the experiment we created choice between two political candidates and experimental subjects were led to conceptualize their political preferences in one of two possible ways: either as supporting the preferred candidate or as opposing the non-preferred candidate. The data indicate that negative preferences show less overall change when exposed to counterarguments. This finding can be incorporated in two theoretical frameworks: dual process theories of attitude change (Elaboration likelihood model) and descriptive decision making theories (Prospect theory). Results are discussed for their implications for the efficacy of political communication

Immobilization of ArRMut11 omega-transaminase for increased operational stability and reusability in the synthesis of 3α-amino-5α-androstan-17β-ol

The aim of this research was to improve the operational stability and enable the reusability of ω-transaminase for synthesis of new enantiopure chiral amines of steroids. Dihydrotestosterone was used to optimize the synthetic procedure of corresponding amino-steroid on a larger scale. The obtained product 3α-amino-5α-androstan-17β-ol was isolated and characterized. The enzyme was immobilized on a methacrylate-based carrier, giving the specific activity of 1.84 U/g of dry polymer. Higher residual activity of the immobilized enzyme in comparison to the soluble form (100 % versus 35%) after 24 h incubation in 35 % dimethylformamide (DMF) was obtained. The soluble enzyme retained 19 % of the initial activity after 2 h incubation in 35 % DMF at 70 °C, while the activity of the immobilized enzyme decreased only to 75 %. Immobilized retained 85 % of initial activity after ten consecutive cycles of 3α-amino-5α-androstan-17β-ol synthesis. We have tested the specificity of the ArRMut11 variant, further increased its stability by immobilization, and used it in several cycles for the synthesis of 3α-amino-5α-androstan-17β-ol. We showed that the enzyme previously evolved for higher stability as the immobilized variant showed more increased stability and high reusability that can more effectively be applied for the biosynthesis of amino steroids

Immobilization of ArRMut11 omega-transaminase for increased operational stability and reusability in the synthesis of 3α-amino-5α-androstan-17β-ol

The aim of this research was to improve the operational stability and enable the reusability of ω-transaminase for synthesis of new enantiopure chiral amines of steroids. Dihydrotestosterone was used to optimize the synthetic procedure of corresponding amino-steroid on a larger scale. The obtained product 3α-amino-5α-androstan-17β-ol was isolated and characterized. The enzyme was immobilized on a methacrylate-based carrier, giving the specific activity of 1.84 U/g of dry polymer. Higher residual activity of the immobilized enzyme in comparison to the soluble form (100 % versus 35%) after 24 h incubation in 35 % dimethylformamide (DMF) was obtained. The soluble enzyme retained 19 % of the initial activity after 2 h incubation in 35 % DMF at 70 °C, while the activity of the immobilized enzyme decreased only to 75 %. Immobilized retained 85 % of initial activity after ten consecutive cycles of 3α-amino-5α-androstan-17β-ol synthesis. We have tested the specificity of the ArRMut11 variant, further increased its stability by immobilization, and used it in several cycles for the synthesis of 3α-amino-5α-androstan-17β-ol. We showed that the enzyme previously evolved for higher stability as the immobilized variant showed more increased stability and high reusability that can more effectively be applied for the biosynthesis of amino steroids

The Effect of Hydroxyl Moieties and Their Oxosubstitution on Bile Acid Association Studied in Floating Monolayers

Bile salt aggregates are promising candidates for drug delivery vehicles due to their unique fat-solubilizing ability. However, the toxicity of bile salts increases with improving fat-solubilizing capability and so an optimal combination of efficient solubilization and low toxicity is necessary. To improve hydrophilicity (and decrease toxicity), we substituted hydroxyl groups of several natural bile acid (BA) molecules for oxogroups and studied their intrinsic molecular association behavior. Here we present the comparative Langmuir trough study of the two-dimensional (2D) association behavior of eight natural BAs and four oxoderivatives (traditionally called keto-derivatives) floated on an aqueous subphase. The series of BAs and derivatives showed systematic changes in the shape of the compression isotherms. Two types of association could be distinguished: the first transition was assigned to the formation of dimers through H-bonding and the second to the hydrophobic aggregation of BA dimers. Hydrophobic association of BA molecules in the films is linked to the ability of forming H-bonded dimers. Both H-bond formation and hydrophobic association weakened with increasing number of hydroxyl groups, decreasing distance between hydroxyl groups, and increasing oxosubstitution. The results also show that the Langmuir trough method is extremely useful in selecting appropriate BA molecules to design drug delivery systems