bluuebunny/crossref_metadata_2025 huggingface dataset:
Prophylactic efficiency of glass-ionomer fissure sealant
Authors: Petrovic Bojan , Markovic Dejan , Filipovic Danka
Published: July 2008

One of the most efficient prophylactic measures in caries prevention is sealing pits and fissures. After improvements of physical and mechanical properties, glass-ionomers are frequently used as sealing materials. The aim of this study was to evaluate the prophylactic efficiency of Fuji VII, a glass-ionomer fissure sealant, through adaptation ability and fluoride reeasing potential assessment using scanning electron microscopic and energy dispersive spectroscopic techniques. The sample consisted of 20 extracted intact human teeth, 10 premolars and 10 molars. Six sections of each tooth were analyzed using SEM. EDS analysis was conducted one week and three months after material placement. The parameters used for the evaluation included: adaptation ability, penetration depth, material structure, integrity of the interfacial zone and ion exchange extent. The sealant penetration depth was observed at 30 X magnification, and the interfacial zone between the material and the enamel at 500-10000 X. EDS was used for quantitative analysis of the material structure, interfacial zone and the enamel surface. The results were statistically analyzed the using chisquare test and descriptive statistical methods. SEM analysis revealed the zone of interaction between the enamel surface and the glass-ionomer with predominant cohesive failures within the sealant material, and satisfactory adaptation ability of the sealing material. The mean value of the penetration was 83% of the total fissure depth, without a statistically significant difference between the tested teeth groups. A lower penetration ability was observed in deep pits and fissures with a larger diameter of unfilled space (p<0.05). EDS analysis revealed the potential of the glass-ionomer for ion exchange with dental tissues. The presence of fluoride ions was detected in 2 sections 3 months after material placement. Glass-ionomers, chemically cured, biocompatible materials demonstrate satisfactory prophylactic characteristics.
The role of synthetic biomaterials in resorptive alveolar bone regeneration
Authors: Kalicanin Biljana , Ajdukovic Zorica , Kostic Milena , Najman Stevo , Savic Vojin , Ignjatovic Nenad
Published: July 2008

The alveolar bone tissue resorption defect has a significant role in dentistry. Because of the bone tissue deficit developed by alveolar resorption, the use of synthetic material CP/PLGA (calcium-phosphate/polylactide-co-gliycolide) composite was introduced. Investigations were performed on rats with artificially produced resorption of the mandibular bone. The results show that the best effect on alveolar bone were attained by using nano-composite implants. The effect of the nanocomposite was ascertained by determining the calcium and phosphate content, as a basis of the hydroxyapatite structure. The results show that synthetic CP/PLGA nanocomposite alleviate the rehabilitation of weakened alveolar bone. Due to its osteoconductive effect, CP/PLGA can be the material of choice for bone substitution in the future.
Adsorption of nicotine on different zeolite types, from aqueous solutions
Authors: Stosic Dusan , Dondur Vera , Rac Vladislav , Rakic Vesna , Zakrzewska Joanna
Published: July 2008

The plant alkaloid, nicotine, is a strongly toxic heterocyclic compound: the lethal dose for an adult human being (40-60 mg) is importantly lower in comparison with the other known poisons such as arsenic or strychni?ne. Cigarettes represent "the most toxic and addictive form of nicotine". Besides the negative effects of nicotine on public health produced by self-administration, recently another potentially very dangerous effect has been recognized: because of its miscibility with water, nicotine can be found in industrial wastewaters, and consequently, in groundwater. Therefore, the problem of nicotine removal from aqueous solutions has became an interesting topic. In this work, the removal of nicotine has been probed by adsorption on solid materials. Adsorption of nicotine on different zeolites (clinoptilolite, ZSM-5 and ? zeolite) and on activated carbon was investigated from aqueous solutions, at 298 K. The obtained results are presented as adsorption isotherms: the amount of adsorbed nicotine as a function of equilibrium concentration. These data were obtained from the residual amount of nicotine in the aqueous phase, by the use of UV spectroscopy. The highest amounts of adsorbed nicotine was found for activated carbon and p zeolite (~ mmol?g-1). The attempt to modify the adsorption properties of ZSM-5 zeolite has been also done: ZSM-5 was modified by ion-exchange with VIII group metal (Cu2+ and Fe3+). In addition, the adsorption of nicotine on ZSM-5 zeolite with different Si/Al ratios has been done. It has been noticed that ion-exchange did not improve the adsorption possibilities, while the adsorption was importantly lower in the case of higher silicon content in ZMS-5 structure. 13C NMR spectra were collected for suspensions formed of solid adsorbent and aqueous solution of nicotine; in this way, the part of nicotine molecule which is most probably connected with the adsorbent was recognized.
Zn-Mn-O: Ferromagnet at room temperature
Authors: Milivojevic Dusan , Blanusa Jovan , Spasojevic Vojislav , Kusigerski Vladan , Babic-Stojic Branka
Published: July 2008

Semiconductor Zn-Mn-O crystallites were synthesized by a solid state reaction method starting from the thermal decomposition of the appropriate oxalates. Samples were thermally treated in air at temperatures ranging from 400 to 900?C. The nominal concentrations of manganese werex = 0.01, 0.02, 0.04 and 0.10. The samples were investigated by the X-ray powder diffraction method, magnetization measurements and by electron paramagnetic resonance. X-ray diffractgrams show a dominant wurtzite structure of Zn-Mn-O. Room temperature ferromagnetism was observed in Zn-Mn-O samples with manganese concentrations x ? 0.04, thermally treated at low temperature (500?C). The saturation magnetiza?tion for the sample with x = 0.01 was 0.05 ?B/Mn. The room temperature ferromagnetism seems to be due to the diffusion of Zn into the Mn-oxides grains.
Calculation of phase equilibria of the Ag-In-Sb system by the calphad method
Authors: Borisov Ivana , Manasijevic Dragan , Zivkovic Dragana
Published: July 2008

The ternary Ag-In-Sb system is a promising candidate for use as a Pb-free solder. The results of phase equilibria calculation by the CALPHAD method are presented in this study. The isothermal section at 400?C was calculated using optimized thermodynamic parameters of the constitutive binary systems. Calculated vertical sections from the indium and antimony corners were compared with the DTA results from this study and from the literature.
The influence of fullerenol on antioxidative enzyme activity in irradiated human erythroleukemic cell line (K562)
Authors: Bogdanovic Visnja , Stankov Karmen , Nikolic Aleksandra , Icevic Ivana , Solajic Slavica , Bogdanovic Gordana , Djordjevic Aleksandar
Published: July 2008

Cell culture K562 samples were treated with fullerenol (C6o(OH)24) at a concentration of 10 nmol/mL and thereafter irradiated with X-rays (24Gy). The activity of gamma-glutamyltransfrease (?-GT), total superoxide-dismutase (SOD) and glutathion-peroxidase (GSH-Px) was determined 1, 24 and 48 hours after irradiation. Irradiation induces an increase in the activity of all the investigated enzymes. Fullerenol in the applied dose decreased the ?-GT activity 24 and 48 h after irradiation. The total SOD activity is increased in both pretreated groups except in the iradiated group at the 48th hour. Treatment with fullerenol before irradiation increased GSH-Px activity in irradiated groups and decreased it in the control groups.
Synthesis of copolymer of styrene and ethylhexyl-methacrylate for the application as sizing agent during paper production
Authors: Radovanovic Itana , Jeremic Katarina , Jovanovic Slobodan
Published: July 2008

Experimental results obtained during investigation of emulsion co-polymerization of styrene (ST) and ethylhexylmethacrylate (EHA) in the presence of cationic or mixtures of cationic and nonionic surfactants are presented in this paper. Potassium persulfate is used as an initiator and hexadecyltrimethylamonium chloride as cationic and ethoxilated benze-nealkane (Triton, N-101) as nonionic surfactant. The influence of concentration of initiator and surfactant, as well as the influence of temperature on copolymer yield and stability of the obtained product was investigated. The electrical charge of the synthesized copolymer particles was determined by electrophoresis. It was found that the particles were positively charged. The zeta potential was equal to 2.5-1CT2 V, which made copolymer dispersion stable for one year. Besides, the possibility of hydrophobization of cellulose fibers by using dispersion of synthesized poly(ST-co-EHA) was qualitatively determined. It was shown that the dispersion could be used for Wet End and surface Sizing Agents of Paper.
Reconstruction and modernization of factory "Hartija Kocani", Macedonia
Authors: Krgovic Milorad , Markovic Aleksandar , Ristovski Vojislav , Rankovic Dragan , Isakov Acko
Published: July 2008

This work presents the reconstruction and modernization of Factory HARTIJA Kocani, for production of high quality graphic paper. Part one analyses the goal of modernization and the approach to its realization. Part two describes the pre-reconstruction state and points to the trouble spots and technical shortcomings of the paper machine. Part three shows the state of technology after the modernization. Here, the companies that took part in realization of project are presented and the quality of their engagement is graded. The final part gives the evaluation of usefulness of the reconstruction and modernization. The evaluation is given for reaching projected capacity and quality, as well as for financial efficiency of the investment, i.e. the price of the execution of the project assignment.
Biological control and management of the detoxication wastewater treatment technologies
Authors: Topalova Yana
Published: July 2008

Detoxication technologies require the combination of theoretical and practical knowledge of xenobiotic biodegradation, wastewater treatment technologies, and management rules. The purpose of this complicated combination is to propose specialized strategies for detoxication, based on lab- and pilot-scale modeling. These strategies include preliminary created algorithms for preventing the risk of water pollution and sediments. The technologies and algorithms are essentially important outcome, applied in the textile, pharmaceutical, cosmetic, woodtreating, and oiltreating industries. In this paper four rehabilitation technologies for pretreatment of water contaminated by pentachlorophenol (PCP) have been developed in the frame of the European and Bulgarian National projects. Emphasize is put on the biological systems and their potential of detoxication management. The light and transmission electron microscopy of the reconstructed activated sludges the microbial, kinetic and enzymological indicators are presented and approved as critical points in the biocontrol.
Extraction of green tea and drying with a high pressure spray process
Authors: Meterc Darja , Petermann Marcus , Weidner Eckhard
Published: July 2008

Green tea is a beverage widely consumed throughout the world and is produced from non-fermented leaves of Camellia Sinensis. Traditionally, green tea leaves are extracted with water. To form solid products, these aqueous products have to be dried. The main focus of the investigation is how to avoid antioxidant degradation during solvent removal. The work was separated in two major sections, firstly investigation of the extraction process secondly, optimizing of the drying process. In the first experiments extractions with different solvents (H2O, EtOH and MeOH), at different temperatures (20, 40, 60 and 80 ?C) and extraction times (15, 30, 60, 90 and 120 min) were preformed to obtain optimum conditions for further processing. For further work extracts obtained with water extraction at 80?C for 15 min were used. In the PGSS (Particles from Gas Saturated Solutions) drying process, extracts with up to 98 wt % water are mixed with preheated carbon dioxide in a static mixer in order to obtain a homogenous mixture. The mixture is led via a single path nozzle into a spray tower. Driven by the expansion of the gas, fine droplets are formed and the heated gas evaporates the solvent, which is exhausted together with CO^ by a blower. Fine powder is formed and collected in the spray tower. The amount of solvent which is to be removed and the residual humidity obtained in the product depend strongly on flow rate and temperature of the gas. From obtained results it can be seen, that high pre-expansion temperatures Tp (145 ?C) cause degradation of polyphenols (1.05 wt %). Maintaining Tp at approximately 130 ?C and lower gave satisfying results; total amount of polyphenols in the obtained powders was between 4.97 and 8.77 wt %. Temperature in spray tower ranging from 33 to 65 ?C has no significant effect on the amount of total polyphenols, but higher temperature results in lower water residue in the sample.
Supercritical CO2 impregnation of polyethylene components for medical purposes
Authors: Gamse Thomas , Marr Rolf , Wolf Christian , Lederer Klaus
Published: July 2008

Modem hip and knee endoprosthesis are produced in titanium and to reduce the friction at the contact area polymer parts, mainly ultra-high molecular weight polyethylene (UHMW-PE), are installed. The polyethylene is impregnated with a-tocopherol (vitamin E) before processing for remarkable decrease of oxidative degradation. Cross linked UHMW-PE offers much higher stability, but a-tocopherol cannot be added before processing, because a-tocopherol hinders the cross linking process accompanied by a heavy degradation of the vitamin. The impregnation of UHMW-PE with a-tocopherol has to be performed after the cross linking process and an accurate concentration has to be achieved over the cross section of the whole material. In the first tests UHMW-PE-cubes were stored in pure a-tocopherol under inert atmosphere at temperatures from 100 to 150 ?C resulting in a high mass fraction of a-tocopherol in the edge zones and no constant concentration over the cross section. For better distribution and for regulating the mass fraction of a-tocopherol in the cross linked UHMW-PE material supercritical CO2 impregnation tests were investigated. Again UHMW-PE-cubes were impregnated in an autoclave with a-tocopherol dissolved in supercritical CO2 at different pressures and temperatures with variable impregnation times and vitamin E concentrations. Based on the excellent results of supercritical CO2 impregnation standard hip and knee cups were stabilized nearly homogeneously with varying mass fraction of a-tocopherol.
New functionalities in cellulosic fibers developed by chemical modification
Authors: Kostic Mirjana , Skundric Petar , Praskalo Jovana , Pejic Biljana , Medovic Adela
Published: July 2008

This paper gives an overview of the current state in the field of cellulosic fibers functionalization by chemical modification. The emphasis is placed on the selective (periodate and TEMPO oxidation) and non-selective (permanganate and peroxide) cellulose oxidation, non-conventional methods for obtaining man-made cellulosic fibers, methods for obtaining antimicrobial cellulosic fibers, as well as method for obtaining two-component polysaccharide fibers. To provide evidence on the achieved functionalities we mainly used capillary rise method, moisture and iodine sorption method, water retention power, NaOH uptake, different ions sorption, Cu-number, carbonyl-and carboxyl-selective labelling and antimicrobial tests.
Biotechnology: Challenge for the food industry
Authors: Popov Stevan
Published: July 2008

According to the broadest definition, biotechnology is the use of living matter (plants, animals and microorganisms) in industry, environment protection, medicine and agriculture. Biotechnology takes a key position in the field of food processing during thousands of years. Last about fifty years brought dynamical development of knowledges in the natural sciences especially in domain of genetics and manipulation of genes. Biotechnology for which active role in the on-coming times could be foreseen, not only with respect of R&D, but also in general technological development represents scope of priority in the USA and in European Union (EU) as well. It is accepted that the results achieved in biotechnology oversize scientific domain and find their entrance into economics, legislation, quality of life and even of politics. Corresponding with the definition of biotechnology as "the integration of natural sciences and engineering in the application of microorganisms, cells, their components and molecular analogues in production (General assembly of the European federation for Biotechnology, 1989) European Commission (1999) adopted the biotechnological taxonomy, i.e. fields and sub-fields of biotechnology. R&D activities in this domain are oriented to eight fields and branched through them. Fields of biotechnology (EC, 1999) are: 1) Plant biotechnology (agricultural cultivars, trees, bushes etc); 2) Animal biotechnology; 3) Biotechnology in environment protection; 4) Industrial biotechnology (food, feed, paper, textile, pharmaceutical and chemical productions); 5) Industrial biotechnology (production of cells and research of cells - producers of food and of other commodities); 6) Development of humane and veterinarian diagnostics (therapeutical systems) 7) Development of the basic biotechnology, and 8) Nontechnical domains of biotechnology. In concordance with some judgments, in the World exist about 4000 biotechnological companies. World market of biotechnological products is increasing at the rate of some 30 percents per year, and in the year of 2000 amounted to about 140 billions of US$. Owing to this, biotechnology became one of the most intensive industries in the world. American biotechnological industry spent even in the year of 1998 about US$ 10 millions for R&D activities. European Union included the development of biotechnology into its R&D programs and projects somewhere during eighties of the last century.
Environmental-friendly wool fabric finishing by some water plant extracts
Authors: Smelcerovic Miodrag , Mizdrakovic Mirjana , Djordjevic Dragan
Published: July 2008

In this article, environmental-friendly finishing of wool fabric were processed with several water extract plants, such as hibiscus, St. John's wort, and marigold. The plant extracts have good basis in the commercial dyeing of wool, for garment and carpet industry. At the same time, the environmental-friendly finishing by water extracts plants shows very good fastness of the antimicrobial properties and coloration of wool fabric. From an ecological viewpoint, the substitution of chemical dyes with "natural products" may represent not only a strategy to reduce risk and pollutants but also an opportunity for new markets and new businesses, which can expend involving of ecology in trade policy.
Application of inverse gas chromatography for polymer characterization
Authors: Nastasovic Aleksandra , Onjia Antonije , Milonjic Slobodan , Jovanovic Slobodan
Published: July 2008

The possibility of polymer characterization by inverse gas chromatography (IGC) was illustrated with the study of sorption properties of macroporous crosslinked poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate), PGME, synthesized by suspension copolymerization, and copolymer modified with ethylene diamine, PGME-en. The data collected from IGC experiments at infinite dilution are used for the calculation of the thermodynamic parameters of adsorption, dispersive components of the surface free energies, and the acid/base constants. .
Semi-interpenetrating networks based on POLY(N-isopropyl acrilamide) and POLY(N-vinylpyrrolidone)
Authors: Zugic Dragana , Spasojevic Pavle , Djonlagic Jasna
Published: July 2008

Three series of semi-interpenetrating polymer networks based on cross-linked poly(N-isopropylacrylamide), PNIPA, and 1, 2 and 3 wt% of linear poly(N-vinylpyrrolidone), PVP, were synthesized in order to improve the mechanical properties of PNIPA gels. The effect of the incorporation of the linear PVP polymer into the temperature responsive networks on the phase transition temperature, swelling behavior and mechanical properties was studied. Polymer networks with four different crosslinking densities were prepared with various molar ratios (25/1 to 100/1) of the monomer (N-isopropylacrylamide) to the cross linker (N,N'-methylene-bisacrylamide). The hydrogels were characterized by determination of the equilibrium degree of swelling at 25 ?C, the dynamic shear modulus and the effective crosslinking density, as well as the ultimate hydrogel properties, such as the tensile strength and elongation at break. Furthermore, the deswelling kinetics of the hydrogels was also studied by measuring their water retention capacity. The inclusion of the linear hydrophilic PVP in the PNIPA networks increased the equilibrium degree of swelling, the highest values of which were obtained for samples with 2 and 3 wt% of PVP and the NIPA/MBA molar ratio of 75/1 and 100/1. The highest reinforcement effect, evaluated from the ratio of G'red(semi-IPN) to G'red(PNIPA), was obtained by incorporation of 2 wt% PVP. The tensile strength of the semi-IPNs reinforced with linear PVP was higher than that of the PNIPA networks. The elongation at break of these semi-IPNs varied between 22 and 55%, which are 22^11% larger than those for single PNIPA networks. The tensile measurements confirmed that the presence of 2 wt% of the linear polymer significantly reinforced the PNIPA network.
Some sharp Ostrowski-Grüss type inequalities
Authors: Liu Zheng
Published: July 2008

Using a variant of Gr?ss inequality, to give a new proof of a well known result on Ostrowski-Gr?ss type inequalities and sharpness of this inequality is obtained. Moreover, a new general sharp Ostrowski-Gr?ss type inequality is given.
Some properties of C-reflexive locally convex spaces
Authors: Radenovic Stojan
Published: July 2008

In this note, we shall prove that the class of C-reflexive spaces is stable with respect to separated quotient, arbitrary product and sum, which is not the case for the closed subspaces and the dense hyper planes. If the quotient mapping lifts compact disks, then the class of C-reflexive spaces is three-space stable.
Stress and it's consequences: A review of transactionist theory
Authors: Zotovic Marija
Published: July 2008

The aim of this paper is to discuss the most important questions concerning stress and its effects on mental health. The author accepts transactionist theory, which basic assumptions are presented in the text. Besides transactionist, reductionist and interactionist models of stress and stress related disorders are explained, as well as the advantages of transactionism. Wider implications and importance of transactionist theory are also pointed.
From 'out there' to 'in between': Preschoolers' interpretation of televised images
Authors: Korac Nada
Published: July 2008

Two studies investigated preschoolers' understanding of how televised images relate to the reality they represent: are they seen as merely showing the visual aspect of reality as it is ('world-window' interpretation), or as representing it by way of specific visual means ('media' interpretation). The first study compared the reactions of younger (4 - 5) and older (6 - 7) preschoolers to very short video clips showing some usual and some unusual (impossible) sights. The children were asked whether what they saw on the screen was true and, if not, how it was possible to show it. The analysis of children's explanations indicates a development toward 'media' interpretation: while younger children tend to explain the impossible images by referring to interventions made 'out there', in front of the camera, the older ones tend to explain them by referring to the interventions of the medium itself. In the second study some of the older preschoolers were given a brief visual literacy training(Videolab method). In the subsequent testing these children demonstrated faster movement toward 'media' interpretations. Cognitive-developmental and educational implications of these findings are discussed.
Close partner relationships
Authors: Stefanovic-Stanojevic Tatjana
Published: July 2008

According to the theory of emotional attachment, specific emotional relationships are being established at an early age between a child and its parents. On the basis of the quality of these relationships the child creates the so-called internal working model ie the image of itself as well as others. The working model persists throughout one's lifetime, shaping in part the quality of adult relationships. Thus, a dominant adult relationship is a close, partner or love one. Within the indicated theoretical context, we were interested in finding out whether there is a statistically significant link between the emotional ties of parents and their children formed in early childhood. The investigation included 180 grown-ups of the same sex and age. For investigating close partner relationships the test Experience in Close Relationship by the American authors (Brenan K.A., Clark C.L., & Shaver P.R. 1998.) was used, while the early emotional relationships were investigated using a test which has been the only one so far to measure this quality in adults - Adult Attachment Interview, (Main M., Casidy J., & Kaplan N., 1985). The results show there is a statistically significant link between the observed variables.
Canonical relations between intelligence and aggressiveness
Authors: Savicevic Dusan
Published: July 2008

Relation between results obtained from 25 tests for estimation of efficiency of perceptual, serial and parallel processor and 8 tests that estimate different modalities of aggressiveness, were analyzed under the biorthogonal model of canonical correlation analysis, on a sample of 647 male subjects, age between 19 to 27. The results show that there is significant, medium high (0,65), logically negative canonical correlation between cognitive efficiency and aggressiveness. Canonical factor derived from cognitive tests was similar to general cognitive factor because all cognitive tests had substantial correlation with it, whereby correlations of tests of serial processing were systematically higher than correlation of tests of parallel and particularly of perceptual processing. Canonic factor derived from tests of aggressiveness was not similar to invert scaled factor of aggressiveness of second order because tests of basic aggressiveness and impulsiveness that were otherwise dominant salient of general factor of aggressiveness, did not have significant correlation with canonical factor derived from tests of aggressiveness. According to that, it seams that inferior functioning of cognitive and particularly serial processor is connected only to those modalities of aggressiveness where there are also disorders of other conative regulators, especially systems for coordination and control of conative functions, but not with basic aggressiveness. That, basically biological characteristic of system for regulation and control of attack reaction, is not, according to all, in significant correlation with efficiency of cognitive processors.
Objective constraints of figural goodness
Authors: Markovic Slobodan
Published: July 2008

The effects of uniformity, compactness and symmetry on pattern goodness estimates were evaluated in three experiments. Ss were asked to choose the pattern which looks the best in respect to other patterns from given set. Patterns within sets differed from each other in uniformity (Experiment 1), compactness (Experiment 2) and symmetry (Experiment 3). Regression analyses indicated that symmetry was a single good predictor of the frequency of good pattern choice. This result is connected with Koffka's concept of perceptual economy: uniformity and compactness have perceptual advantages in the restricted situations (low energy disposal), while symmetry prevails in unrestricted conditions (high energy disposal).
Dynamics of serial position change in probe-recognition task
Authors: Fific Mario
Published: July 2008

Relationship between practice and serial position effects was investigated, in order to obtain more evidence for underlying short-term memory processes. The investigated relationship is termed the dynamics of serial position change. To address this issue, the present study investigated mean latency, errors, and performed Ex-Gaussian convolution analysis. In six-block trials the probe-recognition task was used in the so-called fast experimental procedure. The serial position effect was significant in all six blocks. Both primacy and recency effects were detected, with primacy located in the first two blocks, producing a non-linear serial position effect. Although the serial position function became linear from the third block on, the convolution analysis revealed a non-linear change of the normal distribution parameter, suggesting special status of the last two serial positions. Further, separation of convolution parameters for serial position and practice was observed, suggesting different underlying mechanisms. In order to account for these findings, a strategy shift mechanism is suggested, rather then a mechanism based on changing the manner of memory scanning. Its influence is primarily located at the very beginning of the experimental session. The pattern of results of errors regarding the dynamics of serial position change closely paralleled those on reaction times. Several models of short-term memory were evaluated in order to account for these findings.
Multiple traumatisation as a risk factor of post-traumatic stress disorder
Authors: Savjak Nadezda
Published: July 2008

Paper presents a part of results obtained in 1998 within action study of the psychological effects of war traumatisation in Republika Srpska. Special attention is paid to the additional impact of multiple exposure to war sufferings regarding the degree of the traumatisation (the loss of loved ones, direct life threat, the participation in combats, and the testimony of the death of other people). 229 persons were assessed in 8 towns of Republika Srpska. The comparison of the results of refugees and domicile persons at the Reaction Index - Revised speaks in favour of their significantly higher vulnerability even after three years after the end of war. Total degree of the traumatisation, as well as the symptoms of intrusion, avoidance, and hyper-arousal are significantly more frequent. In 42.5% of refugees (in relation to 26.7% of domicile persons) there is PTSP risk. The intensification of criteria proves that 17% of refugees are at high risk (in relation to 5.2% of the domiciled). It is obvious, that refuge presents traumatic event for many people, and not only chronic burden. The results suggest that the effect of direct jeopardy, combat stress, and the testimony of somebody else?s death are fading in time, but that the culmination of tangible, social, and human losses in refuge is serious risk factor for mental health.
Psychological and social-cultural factors of the origination and treatment of anorexia nervosa
Authors: Djurovic Dusanka
Published: July 2008

The paper provides and overview of modern literature on psychological and social-cultural factors of anorexy etiology and psychotherapy. Nutrition problems are pointed out, which are necessary to be solved before any psychotherapeutic intervention, and it also provides the overview of our therapeutic approach efficiency.
The role of dysfunctional attitudes in depressive mood and the mediation effect of "hot" evaluative cognitions
Authors: Maric Zorica
Published: July 2008

Previous research has found dysfunctional attitudes to be elevated in persons with elevated depressed mood, and a facet of dysfunctional attitudes referred to as Approval by Others has been a significant predictor of severity of depressed mood. The present study evaluated relations between Approval by Others and depression and examined the role of dysfunctional evaluative cognitions over life problems and hassles as a mediator of this relationship among 100 undergraduates. Approval By Others facet was found to be a significant predictor of severity of depressed mood. However, further analysis provided strong evidence that the effect of this dysfunctional attitudes facet is mediated by evaluative cognitions over life problems and hassles. Results are discussed in the context of previous research and cognitive behavioural therapy practice.
Ethnical distance of the citizens of Republika Srpska and the Federation of Bosnia and Herzegovina to the nations of former Socialist Federal Republic of Yugoslavia
Authors: Puhalo Srdjan
Published: July 2008

The paper presents the study of Ethnical distance with the citizens of Bosnia and Herzegovina. The study was made using Bogardus' scale of social distance, on 1000 interviewees of the Federation of BiH and 850 interviewees of Republika Srpska. The citizens of the Federation of Bosnia and Herzegovina reject the Romas the most, followed by the Albanians and Macedonians. This is followed by the Serbs and Montenegrians, while Slovenians and Croats are the least rejected. Prejudices of the citizens of Bosnia and Herzegovina to the Romas, Albanians, and Macedonians are much more important for the rejection or accepting of offered relations, than it was the case with open hostility and war conflicts with the Serbs, Montenegrians, and Croats. In the Federation of Bosnia and Herzegovina a distinction is made in the degree of ethnical distance of Bosniaks and Croats to the nations who lived in the former Socialist Federal Republic of Yugoslavia. Offered relations are more rejected by the Croats than by the Bosniaks. The citizens of Republika Srpska accept the Muslims (Bosniaks) and Romas the least. This is followed by the Croats, Slovenians, and Macedonians, and the Montenegrians are rejected the least. The citizens of Republika Srpska refuse that they or the members of their family marry a member of another nation. Thus they object any possibility for the members of other nations to be found on managing position, or any situation where they themselves would be in a subordinate position in society in relation to the members of other nationalities.
Cognitive dissonance between religious and secular social attitudes
Authors: Markovic Jelena
Published: July 2008

The initial finding of the study, which served as the basis for the exploration of cognitive dissonance between religious and secular behavioral norms, was revealed in a tendency of the majority of religious students to accept behavioral norms, attitudes and believes (concerning interpersonal relationships and reproduction-related ethical issues) which are not supported by Orthodox Christian Church viewpoint and teachings. However, certain cognitive and value system consistency appeared to exist: the intensity of religiousness was related to lower degrees of secular norms approval. It has been found that religious and nonreligious subjects differ significantly in their preference of the strategy used to maintain balance between dissonant religious and secular attitudes- in 3 out of 4 issues considered in the study. Religious subjects most frequently chose relativism strategy, claiming that some specific exceptions from a general rule or standpoint do not necessarily depreciate it, while nonreligious subjects most frequently chose dualistic viewpoint that principally separated and restricted domains of reasoning on spiritual and worldly issues, making them psychologically irrelevant to one another.
Annotated corpus and the empirical evaluation of probability estimates of grammatical forms
Authors: Seva Nada , Kostic Aleksandar
Published: July 2008

The aim of the present study is to demonstrate the usage of an annotated corpus in the field of experimental psycholinguistics. Specifically, we demonstrate how the manually annotated Corpus of Serbian Language (Kostic, Dj. 2001) can be used for probability estimates of grammatical forms, which allow the control of independent variables in psycholinguistic experiments. We address the issue of processing Serbian inflected forms within two subparadigms of feminine nouns. In regression analysis, almost all processing variability of inflected forms has been accounted for by the amount of information (i.e. bits) carried by the presented forms. In spite of the fact that probability distributions of inflected forms for the two paradigms differ, it was shown that the best prediction of processing variability is obtained by the probabilities derived from the predominant subparadigm which encompasses about 80% of feminine nouns. The relevance of annotated corpora in experimental psycholinguistics is discussed more in detail .
The effect of subordinate and superodinate class in categorization task
Authors: Injac Bozana , Kostic Aleksandar
Published: July 2008

Categorization as a function of position of subordinate instance and superordinate class (e.g. cat-mammal vs. mammal-cat) was investigated in six experiments. Participant's task was to answer (by pressing yes/no key) whether an instance (e.g. cat) and a class (e.g. mammal) are categorically congruent. In Experiments 1, 3 an 5 instance was presented as the first stimulus in a pair, while in Experiments 2, 4 and 6 it was the second stimulus in a pair. In Experiments 1 and 2 instance was presented within a blocked design, while class was varied (e.g. mammal/insect), while in Experiments 3 and 4 the order was reversed, i.e. class was blocked while instances varied with respect to category (e.g. cat/bee). In Experiments 5 and 6 both instances and classes varied. The outcome of the six experiments indicates that categorization latency depends on order of presentation (instance/class vs. class/instance) and class (mammal vs. insect). Categorization time was slower if the first stimulus in a pair denotes a class. Conspicuous deviation was observed for the class of insects where congruent instance/class pairs were categorized slower than non-congruent pairs. There was also a three-way interaction (class x instance: class congruency x order of presentation).
Processing differences between prepositions and nouns
Authors: Radojcic Vesna , Kostic Aleksandar
Published: July 2008

Processing differences between Serbian prepositions and nouns were investigated in two lexical decision experiments. The outcome of the experiments indicate that processing of nouns presented in their citation form is affected primarily by the amount of information (bits) derived from noun's probability. Processing of prepositions appeared to be more complex because, in addition to probability of preposition, processing latency is also affected by number of syntactic functions/meanings carried by a given preposition and number of congruent noun cases. None of these factors per se is correlated with processing latencies. However, when combined into a single unit (expressed in bits) significant proportion of processing latency variability has been accounted for. It was shown that prepositions are processed faster than nouns of equivalent frequency and equivalent length. We conclude this on the basis of the observed differences in slope from linear regression, but also on the basis of differences in averaged RTs for the two word types.
Critical thinking between fashion and thoughtfulness: Towards the theoretical foundation of concept
Authors: Pesic Jelena
Published: July 2008

Based on the analysis of socialization context within modern society, we justify development of critical thinking as an important educational goal, as well as the necessity of thoughtful, theoretically founded approach in its realization. Discussed difficulties in understanding the genuine meaning of critical thinking concept are related to the complexity of concept itself, but also with diverse and heterogeneous context it is used in, and superficial, purely pragmatic and theoretically unfounded practice. Thus, the paper is an attempt to identify the key theoretical problems regarding the conceptualization of critical thinking, and an invitation to serious consideration of its meaning, importance and practical implications.
Allomorphic development: A major postulate of Vygotskian theory
Authors: Miric Jovan
Published: July 2008

The article stresses the importance of Vygotsky?s postulates on evolution and history for understanding his developmental theory, focusing especially on his thesis on the clear-cut replacement of evolution by history. That thesis shaped the general theoretical plane consisting of several opposing and almost mutually exclusive pairs of solutions, such as biology - culture, individual - collective, animal - human, evolution - history etc. Such general solutions offer too narrow a framework for elaborating a theory of ontogenesis. This is the background on which the true meaning of the postulate of allomorphic development is presented, along with an analysis of several more specific related theses. The article ends with a critical review of Vygotsky?s general postulates, pointing out to the ideological dimension of his developmental psychology.
Toward a Vygotskian theory of textbook
Authors: Plut Dijana , Pesic Jelena
Published: July 2008

This is an attempt to place the problem of textbook theory into a new frame of reference provided by cultural-historical theory of development, using the idea about cultural-historical mediation of individual development and concept of CST as a basic analytical concepts. The new frame of reference introduces a new language on textbooks, opening a range of new research problems, while dealing with the old ones in a new and more complex way. Textbook is shifted from the usual pedagogic-didactic setting and placed in a more basic and cultural context. The paper is an attempt to bring the concept of cultural tools to a completely operational level, as well as to test the actual power of that concept by identifying CST in textbooks. Furthermore, this paper is an attempt elaborate the forms of social assistance that constitute the zone of proximal development, seen as the characteristics of joint activities of the child and a more competent participant (which is "hidden?, i.e., indirectly present, in this case). Vygotsky never specified the forms of social assistance, but rather gave general prescriptions (Moll, 1990), thus presenting one of the central theoretical and practical tasks for the followers of his ideas.
Diagnostic possibilities of three Rorschach indexes for cognitive functioning assessment
Authors: Dzamonja-Ignjatovic Tamara , Djuric-Jocic Dragana
Published: July 2008

The study presents theoretical and empirical comparison of the three indexes in Rorschach Comprehensive System that were developed for psychotic functioning assessment: the Schizophrenia Index (SCZI), the Ego Impairment Index (EII) and the Perceptual Thinking Index (PTI). In spite of the conceptual and nominal differences, these indexes significantly overlap and includes common indicators. The study compared a discrimination value of these three indexes, as well as and theirs indicators and based on the obtained results, tried to formulate a new index as a composite of the best predictors.
The investigation of formal operational thinking on the age 14-19
Authors: Stepanovic Ivana
Published: July 2008

This work deals with formal operations. The following problems were investigated: (1) formal operational thought characteristics, (2) existence of formal operations structured whole, (3) existence of age differences regarding formal operations and (4) existence of sex differences regarding formal operations. There were 339 subjects, from the three age groups (eight grade of primary school, second and fourth grade of secondary school). Formal operations are tested by Bond?s Logical Operations Test. Rasch model was used for data analysis as well as some CTT techniques, basically for testing age and sex differences. The results show that BLOT is easy for our subjects. The hardest items are related to implications and the easiest to correlations and volume conservation. The data confirm assumption of formal operations as structured whole. There are age differences between youngest subjects and other two age groups but there is no differences between younger and older secondary school students. Sex differences were not found. Results were discussed in the light of Piaget's theory and the results of formal operations studies.
Parental styles and the stability of self-esteem in adolescence
Authors: Todorovic Jelisaveta
Published: July 2008

Relationship between parents and children is significantly important for the forming of identity and its affective component of self-esteem. High and stable self-esteem is being developed in certain family conditions through parental influences to which a child is exposed within a family. In this research the results of a role of different parental styles have been presented in forming of stable self-esteem in adolescents. The research has been done in eight secondary school in Nis. The sample was done on N=280 pupils with Global Self-Esteem Rosenberg's scale, and EMBU parental styles scale of Perris-Arrindell's version. This research has shown that stable self-esteem in adolescents is being connected to mother?s emotional warmth and acceptance through the process of parenting. Unstable self-evaluations are connected to inconsistency and overprotection, while rejection leads to stable, but low self-evaluations.
The formal operations: Piaget’s concept, researches and main critics
Authors: Stepanovic Ivana
Published: July 2008

This paper deals with Piaget's concept of formal operations, formal operations researches and critics related to the concept. The first part of the work is dedicated to the formal operations concept. The main characteristics of formal operational thought and formal operations structure, as well as structure logical model are presented in that part of the work. The second part is a review of formal operational researches and it is divided in three parts: (1) problems of researches (2) characteristics of applied methodology and (3) author approaches as a specific research context. In the last part of the work the main critics of formal operations concept are presented and discussed.
Delusion disorder: Neuropsychological aspects
Authors: Leposavic Ivana , Leposavic Ljubica
Published: July 2008

Previous studies concerned with neuropsychological aspect of delusions, were mainly focused on specific forms of this disorder. Comparatively small number of investigations were concerned with cognitive deficiencies accompanying the delusions. The substance of this study includes the detection of neuropsychological disfunctions in patients with persistent delusion disorder, and in tracing of these cognitive distortions to appropriate brain regions. Besides, characteristics of attribution style in these patients are analysed, from the aspect of their connections with unadjusted localized input for their reasoning system. The investigation is designed as a comparative study. The sample includes: a group of patients with persistent delusion disorder; a group of patients with paranoid schizophrenia; a group of healthy individuals. The participants have been tested by a neuropsychological battery that represents the following cognitive functions: attention, memory, vizuospatial and vizuoconstruction organization, executive ability, verbal divergent thinking. Projective Rorschach's method was used for estimation of attribution style.