Addressing inequality and poverty with tax instruments

There is a consensus, in both academia and economic policy circles, that the reform of the personal income tax system in Serbia is necessary one. Two frequently discussed reform scenarios are East European style flat tax and the comprehensive income tax model of Western Europe. Most Central and Eastern European (CEE) countries have recently reformed their income tax systems by introducing some form of flat tax scheme, while in numerous countries of Western Europe the possibility of flat tax reform is also seriously considered. Opponents of the reform usually stress the adverse distributional effects of flat tax schemes. The aim of our paper is to contribute to the empirical literature on the distributional effects of alternative tax reform scenarios. The analysis is based on the tax and benefit micro-simulation model for Serbia (SRMOD). The results suggest that redesigning the existing income tax system so as to introduce a uniform tax rate and increase the basic allowance would somewhat reduce inequality and improve vertical inequity in taxation. On the other hand, in the case of the introduction of comprehensive income tax, considerably larger equalizing and progressivity effects would be achieved. At the same time, since in both cases redistribution will not affect the bottom decile group, no significant effects (in either cases) on poverty reduction will be achieved

Design of peptide and small molecule inhibitors of cyclin dependent kinase 9 / cyclin T1 protein-protein interaction using computational methods

Cilj ove doktorske disertacije je razvoj direktnih inhibitora interakcija u kompleksu CDK9 / ciklin T1. Ciklin zavisna kinaza 9 u kompleksu sa ciklinom T1 čini katalitičko jezgro P-TEFb kompleksa. Inhibicija funkcije P-TEFb kompleksa je od značaja u terapiji više patoloških stanja kod ljudi: nekih tipova maligniteta, HIV-1 infekcije, hipertrofije miokarda, hroničnih inflamatornih bolesti. Postojeći inhibitori P-TEFb funkcije imaju ograničenu selektivnost dejstva, koju je moguće poboljšati primenom direktnih inhibitora CDK9 / ciklin T1 interakcije. U ovom istraživanju urađena je in silico studija P-TEFb kompleksa. Ispitana je struktura, hidratisanost i dinamika vezivnih površina kompleksa. Utvrđene su energetski najznačajnije hot spot aminokiseline u strukturi kompleksa i upotrebljene za dalji dizajn inhibitora. Struktura slobodne CDK9, neophodna za dizajn liganada je, u nedostatku eksperimentalno utvrđene strukture, simulirana klasičnom i ubrzanom molekularnom dinamikom. Ispitana je sposobnost vezivne površine kompleksa da interaguje sa ligandima, kao i postojanje, otvaranje i postojanost privremenih hidrofobnih džepova na vezivnoj površini CDK9, pogodnih za vezivanje liganada. Dobijene informacije o vezivnim površinama kompleksa CDK9 / ciklin T1, upotrebljene su za dizajn peptidnih i nepeptidnih inhibitora interakcije. Peptidni inhibitori su dizajnirani po ugledu na strukturu ciklina T1, ali i de novo dizajnom iz aminokiselina. Peptidne strukture sa najpovoljnijom energijom vezivanja za CDK9, iskorišćene su u razvoju nepeptidnih inhibitora. Predložene su strukture potencijalnih nepeptidnih inhibitora interakcije CDK9 / ciklin T1. U okviru ovog istraživanja urađeno je i ab initio ispitivanje prelaznih stanja intramolekulske Heck-ove ciklizacije alilnih alkohola i predloženo je objašnjenje za eksperimentalno zapaženu regioselektivnost procesa.The goal of this doctoral dissertation is the development of direct inhibitors of CDK9 / cyclin T1 protein-protein interaction. Cyclin dependent kinase 9 in complex with cyclin T1 forms the catalytic core of P-TEFb protein complex. Inhibition of P-TEFb function is of significance in the therapy of several pathological states in humans: some malignancies, HIV-1 infection, cardiac hypertrophy, chronic inflammatory diseases. Existing inhibitors of P-TEFb function have a limited selectivity of action, which could be improved with the direct inhibitors of CDK9 / cyclin T1 interaction. An in silico study of the P-TEFb complex was conducted in this research. The structure, hydration and dynamics of the complex binding surfaces were examined. Energetically most significant amino acids, hot spots, were determined and used in the design of inhibitors. The structure of the free CDK9, needed for the ligand design, was, in absence of an experimentally determined structure, simulated using classical and accelerated molecular dynamics. The ability of complex binding surfaces to interact with ligands was examined, as was the existence, opening and persistence of transient hydrophobic pockets on CDK9 interface surface, suitable for ligand binding. Information obtained of the CDK9 / cyclin T1 complex binding surfaces was used in the design of peptide and small molecule inhibitors of this interaction. Peptide ligands were designed using cyclin T1 as a template structure, as well as using de novo design from amino acids. Peptide structures with the most favourable binding energy to CDK9 were utilised in the design of small molecule inhibitors. Structures of potential small molecule inhibitors of CDK9 / cyclin T1 interaction were proposed. An ab initio study of transition states in an intramolecular Heck cyclisation of allyl alcohols was also conducted in this research. An explanation for the experimentally observed regioselectivity of the process was proposed

Protein-protein interakcije u razvoju novih lekova

Protein-protein interactions form the basics of both physiological and pathological processes, which makes them important targets for drug discovery. Structural characteristics of protein complexes, features of their binding interfaces and theoretical foundations relevant to the design of small molecules modulators of protein interactions have been briefly described in this text. Several experimental methods applicable to the design of drugs acting on protein-protein interactions are listed. The research progress achieved so far is illustrated through several examples of successfully designed modulator molecules. Due to the extraordinary significance of protein-protein interactions in living systems and our improved understanding of them, protein-protein interactions are becoming an increasingly important part of drug discovery research projects. Drugs modulating protein-protein interactions are likely going to represent an increasing percentage of therapeutically active compounds.Interakcije među proteinima nalaze se u osnovi kako fizioloških, tako i patoloških procesa, što ih čini važnim metama za razvoj novih lekova. U ovom radu su ukratko prikazane strukturne karakteristike kompleksa nastalih interakcijom proteina, osobine njihovih vezivnih površina i teorijske postavke na kojima se zasniva dizajn malih molekula modulatora proteinskih interakcija. Navedeno je nekoliko eksperimentalnih metoda primenjivih u razvoju organskih molekula koji deluju na protein-protein interakcije. Dosadašnji razvoj istraživanja u ovoj oblasti ilustrovan je kroz više primera uspešno dizajniranih modulatorskih jedinjenja. Zbog izuzetnog značaja u živim sistemima, a zahvaljujući sve boljem razumevanju protein-protein interakcija, one postaju sve važniji deo istraživačkih programa za razvoj novih lekova. Lekovi koji deluju kao modulatori proteinskih interakcija u budućnosti će verovatno predstavljati sve veći procenat terapijski aktivnih supstanci

Electrochemical behaviour of serpentinite and forsterite in ferri/ferro cyanide benchmark redox system

Serpentinite rock collected near Kopaonik Mountain in Serbia is considered as a multiphase assemblage mostly consisting of mineral lizardite. Forsterite has been obtained by chemical-thermal treatment of grounded sample of serpentinite. Electrochemical features of these two materials were investigated by using modified carbon paste electrode (CPE) which included mixing analytes, graphite powder and parafin oil as a binder and packing the mixture in a Teflon holder. Morphological and structural characteristics of the samples were analyzed by SEM and XRD techniques which revealed presence of certain crystal phases and agregates of irregular shapes sized from 10 to 40 μm. Cyclic voltammetry was employed to study their electrochemical characteristics. The peak current height and peak-to-peak separation showed that the electrochemical reaction is quasi-reversible. Kinetic parameters were derived from Tafel analysis. Calculated kinetic parameters indicated prominent electrocatalytic effect of the minerals for ferri/ferro cyanide redox reaction in aquaeous solutionBook Of Abstracts of 4th Conference of The Serbian Society for Ceramic Material

Application of AHP method in cities' certification process

Due to the global phenomenon of competitiveness, which is also present among the cities and municipalities, there is a need to evaluate the cities' strength and potential, or to estimate their value. Aswell as in case of enterprises, the value of cities and municipalities has to be expressed in certain numbers, since this enables their benchmarking, over the time and with competitors. One of the most popular methodologies for evaluating the competitiveness of cities and municipalities is the one introduced by NALED. It includes twelve criteria that cities and municipalities have to satisfy in certain percentage (at least 75%). However, the practice has shown that the successfulness of so far certified cities and municipalities in Serbia is not the same (measured by the sum of attracted direct investments). Therefore the need for the identification of the importance of certification criteria has appeared. The aim of this paper is to check whether all criteria are equally important and to point out the most important criteria for efficiently attracting direct investments. The AHP method is used to determine the weights in the multi-criteria model and the results have shown that NALED's methodology can be and should be improved

Effective determination of clomazone and oxyfluorfen in aqueous samples by differential pulse stripping voltammetry

Two novel types of electrochemical sensors were obtained by chemical deposition of Pt and MoO2 nanoparticles onto multi walled carbon nano tubes (MWCNT) and used for determination of frequently used pesticides clomazone and oxyfluorfen in aqueous media via differential pulse stripping voltammetry (DPSV). Clomazone was determined in 0.1 M phosphate buffer solution at pH 7.0 in the concentration range 0.61-20.56 ng cm-3, with LOQ = 0.61 and LOD = 0.38 ng cm-3. Oxyfluorfen was determined with good reproducibility (RSD <2.4%) in the concentration range 2.5-34.5 ng cm-3, with r = 0.99 and a LOQ of 1.5 ng cm-3. Results were in the same range measured by HPLC/DAD, which was used as comparative method. Structural characterization of the dopped MWCNT performed by Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron (HR-TEM), and X-ray crystallography revealed a preserved MWCNT structure decorated with well dispersed species of the platinum and MoO2 nanoparticles.IX International Scientific Conference "Technics. Technologies. Education. Safety"; June 07-10, 2021; Borovets, Bulgari

Orchid species Anacamptis morio as a potential bioremediator of As, Cd and Pb

In this study concentration of toxic elements as, Cd, and Pb were determined in different soil types and belonging orchid species Anacamptis morio vital parts, in order to examine accumulation patterns and provide new insights about the potential use of this orchid in bioremediation technology. Soils developed on limestone, serpentine, and the chert were subjected to the BCR sequential extraction. Samples of orchid roots and tubers, as underground parts, and stems, leaves, and inflorescences, as above-ground organs, were also analyzed for the content of as, Cd and Pb. During this research, it was observed that metal content in soil is directly proportional to its content in the plant, more specifically in roots, which suggests that A. morio can potentially be used in the phytostabilization of contaminated sites. Values for BCF factors showed Cd immobilization in roots regardless of the soil type. A certain level of arsenic was transferred from roots to leaves indicating the potential for accumulation of this element into aboveground organs. Assessment of the phytoremediation potential of this orchid or another plant species from diverse environments is important as it provides information about the possibility of their future application in environmental remediation programs

The effects of colloidal SiO2 and inhibitor on the solid deposit formation in geothermal water of low hardness

Low solubility of SiO2 and its occurrence in geothermal waters in the form of ionic, colloidal and suspended state are the main cause of the solid deposit occurrence. Certain chemical types of silica, under the influence of Fe2+, Al3+, F−, OH- ions and other micro-constituents, and due to significantly decreased solubility of SiO2, stimulate nucleation, particle growth and solid deposit formation. The aim of this paper is to inhibit the process of nucleation and solid deposit formation by adding originally designed inhibitor in the form of an emulsion, when the total concentration of the present and added colloidal SiO2 is beyond the solubility limit (120 mg/dm3). By turbidimetric, SEM, EDS and XRD analysis, the processes of solid deposit formation were investigated in Vranjska Banja (Serbia) spa geothermal water source (water hardness of 4ºdH), and theoretical and practical conclusions were made

Supplementary data for the article: Ranđelović, D.; Mutić, J.; Marjanović, P.; Đorđević, T.; Kašanin-Grubin, M. Geochemical Distribution of Selected Elements in Flotation Tailings and Soils/Sediments from the Dam Spill at the Abandoned Antimony Mine Stolice, Serbia. Environ Sci Pollut Res 2020, 27 (6), 6253–6268. https://doi.org/10.1007/s11356-019-07348-4

Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/3966]Supplementary material for: [https://link.springer.com/article/10.1007%2Fs11356-019-07348-4

Frequency and approaches in treatment of fractured condylar processes in population of South East Serbia for the period from 2011 to 2017

Introduction: The condyloid process or condylar process (processus condylaris) is the second, more posterior process on the mandible, which takes part in the formation of the temporomandibular joint. Fractures of the condyloid process constitute 25% to 35% of all fractures of the mandible. They rarely occur isolated, whereas they are more often associated with fractures of other localizations on the mandible. Aim: This paper aims at determining the frequency of the fracture of the condyloid process of the mandible in relation to fractures of other localizations; the mechanisms of injury occurrence; as well as the representation of individual surgical procedures within the treatment. Material and Methods: The data obtained from the medical documentation of the Department for Maxillofacial Surgery, the Dentistry Clinic of Niš were analyzed using clinical retrospective study in the period from January 2011 to December 2017. Results: The analysis of the medical documentation established that 343 patients having mandible fractures were treated at the Dentistry Clinic of Niš, at the Maxillofacial Surgery Department in the aforementioned period, out of which 85 patients had a fracture of the condyle and were treated with surgery, while 13 were treated conservatively. Conclusion: It was stated that the mandible fracture most frequently lead to the occurrence of fracture of its condyloid process. Most frequently it occurs with men at the age of 21 - 40 as the consequence of physical violence