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Background/Aim. Liver damage, with potentially serious consequences, is not uncommon in hospitalized cardiac patients. The aim of our study was to determine the risk factor profile for liver damage in patients hospitalized from a deterioration of their acute or chronic cardiac illness. Methods. The study had observational case-control design with retrospective data collections from medical files of adult patients hospitalized in a tertiary health care center. The cases (n = 140) were subjects with novel liver injury (which emerged during hospital stay) and three control subjects were matched (age, date) for each case subject (n = 420). The primary outcome was hepatotoxicity (present or absent) and independent variables were proposed risk factors. Statistical analysis included descriptive methods, hypothesis testing and univariate and multivariate binary logistic regression, with p ≤ 0.05. Results. In the whole study population, there were 432 (77.1%) females and the mean age of patients was 64.1 years [standard deviation (SD) = 10.7, range 24–85 years]. The most common illnesses were coronary heart disease (n = 385), hypertension (n = 334) and arrhythmia (n = 115). Mean value of Charlson Comorbidity Index (CCI) score was 3.8 (SD=1.7; range 1-10) corresponding to estimated CCI 10-years survival rate of 54.4% (SD = 33.5%). In the group of cases, 114 (81.4%) of the patients had hepatocellular, 9 (6.4%) cholestatic and 17 (12.2%) mixed type of hepatic injury. Factors independently associated with hepatotoxic event were previous occasional alcohol intake odds ratio (OR) 96.47; 95% confidence interval (CI) 28.95–321.43; p < 0.001), amiodarone (OR 3.70; 95% CI 1.82–7.53; p < 0.001), enoxaparin (OR 3.29; 95% CI 1.79–6.05; p < 0.001), obesity (OR 2.78; 95% CI 1.15– 6.71; p < 0.023), atorvastatin (OR 2.67; 95% CI 1.33–5.38; p < 0.006) and CCI total score (OR 1.89; 95% CI 1.53–2.34; p < 0.001). Conclusion. Major factors associated with acute liver damage in patients hospitalized in cardiology ward of a tertiary health care institution were patient’s constitutional and habitual characteristics (occasional alcohol intake, obesity, CCI total score) and drugs with known hepatotoxic properties (amiodarone, enoxaparin, atorvastatin).

The aim of the paper is to present various methods for the evaluation of biological maturity which can define the differences between chronological age and biological maturity in young athletes. Biological maturation is a nonlinear process, taking place at all organic levels, differing from the flow of time after birth. From this point of view, there is a need to determine the differences in the rate of biological maturation within the chronological period. Defining the biological maturity of athletes has a multidimensional significance, the evaluation of youth's maturity in comparison with the chronological age has an implicit value, the selection and prediction of sports achievement at the individual level is crucial for the planning and programming of the training process. Maturity evaluation feedback has a function in preventing and restraining injuries of athletes who are behind their peers. Athletes who are advanced in comparison to their chronological generation, in younger selections, reach a plateau of sports performance early, which can negatively affect success in the senior period. The paper presents the basic methods of evaluation of biological matrices used in the diagnosis of young athletes. Biological maturity can be determined by means of radiography, anthropometric measurements, and sex-based indicators.

The aim of this paper is to define the population indicators of the nutritional status among the working population of the Republic of Serbia based on the value of Body Mass Index (BMI). The sample consisted of a total of 7.125 working subjects, among which 4.525 males (63.51%) and 2.600 females (36.49%). The subjects were from the following regions: Northern Serbia-Vojvodina, Capital city - Belgrade, Central Serbia, Western Serbia, Southern Serbia and Eastern Serbia. The average BMI values based on test groups of men and women were 26.53±4.07 and 24.07±5.09 kg, respectively. On the basis of the obtained results, it was determined that statistically significant BMI differences exist among subjects in general, i.e. in relation to gender (F=58.412, p

Introduction: Myasthenia gravis (MG) can be associated with other autoimmune diseases (AID), most frequently with Hashimoto's thyroiditis, systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Familial occurrence (FOMG) is rare and it exists in 3.5-4.2% patients with MG. Aim: To determine the occurrence of FOMG, the occurrence of AID associated with MG and to identify potential risk factors for developing MG in a cohort of patients from Belgrade. Material and Methods: This study gathered data from 453 patient histories from the period from1992-2014, from the Clinic of Neurology, Clinical Center of Serbia. Three analyses were performed. The first one measured the frequency of associated AID in patients with MG. In the second one, patients who had MG associated with AID were compared to patients without associated AID. The third one included patients with FOMG and compared them with patients without FOMG. The demographic and clinical characteristics of these patients were analysed and comparisons were made between observed and control groups. Results: The associated AID were present in 54 (11.9%) patients, the most frequent was Hashimoto thyreoiditis (4%), then SLE (1.3%), and RA, polymyositis and pernicious anaemia (0.9%). Patients with co-occurrence of MG and other AID were, in comparison with control group, more often female, and the difference was on the border of statistical significance (p=0.056). They had late onset MG (LOMG) more frequently, a mild form of MG and positive anti-AChR antibodies, but these differences weren't statistically significant. FOMG was seen in 2.2% of patients. They had LOMG more frequently, were predominantly men, seropositive, and with mild form of the disease, but with no statistical significance compared to the control group. Conclusion: In the Belgrade cohort, MG was often associated with other AID, while FOMG was relatively rare. There was no significant difference, statistically, in the observed clinical and demographic characteristics of analysed groups, compared to control groups.

Waste disposal is an important element of integrated waste management. In order to dispose of waste that is free of environmental risk, the proper design of landfills during their construction and/or closure is necessary. The first section of the paper presents the current state of landfills in Serbia, the second deals with problems in project design of landfills, especially in regard to their: a) program of waste disposal; b) impermeable layer; c) leaching collection and treatment; and d) gas collection and treatment. Analysis shows that many modern landfills in Serbia do not meet environmental protection requirements, therefore, they need reconstruction. All existing landfills owned by municipalities, as well as illegal dump sites, should be adequately closed. This paper presents the guidelines for successful landfill design which are to serve to meet the requirements and recommendations of Serbian and European regulations. Sound design of landfill technological elements should insure full sustainability of landfills in Serbia.

Software for chemical processes modeling and simulation, in the past few decades, play an important role in the development of chemical-process industry with their growing capabilities and wide range of application. Usage of process simulators in Serbia for the process design is very limited. This paper gives a brief overview of the numerous process simulators that are used in the chemical-process industry today. The conceptual design is responsible for most of the investment costs in chemical process industry. Importance of precise design on preliminary level is obvious. Wrong decisions made at the conceptual level could be carried out throughout the chain in process design to the detailed design procedures and procurement of equipment. Although preliminary design phase comprises only about 2% of the total cost of the project, it contributes significantly to the reduction of cost of the project by more than 30%. Therefore process simulators play important role in elimination of unnecessary errors in basic process design. Here is also shown a case study of parallel process simulated in different process simulators which tests the results, the reliability and usefulness of these programs in solving specific engineering tasks. Comparison of given simulation results confirm that the modern process simulators are at high level of confidence, no matter they are based on different models, equations, methods, operations, interfaces or data bases. Usage of software speeds up the arrival of optimized solution during the design and the operational procedures. Therefore software have significant impact on reducing time of pre-project phase such as research, conceptual design, and proving project abilities. It’s development lead to faster commercialization of industrial ideas. [Projekat Ministartsva nauke Republike Srbije, br. TR 34009]

Storage of crude oil and petroleum products inevitably leads to evaporative losses. Those losses are important for the industrial plants mass balances, as well as for the environmental protection. In this paper, estimation of evaporative losses was performed using software program TANKS 409d which was developed by the Agency for Environmental Protection of the United States - US EPA. Emissions were estimated for the following types of storage tanks: fixed conical roof tank, fixed dome roof tank, external floating roof tank, internal floating roof tank and domed external floating roof tank. Obtained results show quantities of evaporated losses per tone of stored liquid. Crude oil fixed roof storage tank losses are cca 0.5 kg per tone of crude oil. For floating roof, crude oil losses are 0.001 kg/t. Fuel oil (diesel fuel and heating oil) have the smallest evaporation losses, which are in order of magnitude 10-3 kg/tone. Liquids with higher Reid Vapour Pressure have very high evaporative losses for tanks with fixed roof, up to 2.07 kg/tone. In case of external floating roof tank, losses are 0.32 kg/tone. The smallest losses are for internal floating roof tank and domed external floating roof tank: 0.072 and 0.044, respectively. Finally, it can be concluded that the liquid with low volatility of low BTEX amount can be stored in tanks with fixed roof. In this case, the prevailing economic aspect, because the total amount of evaporative loss does not significantly affect the environment. On the other hand, storage of volatile derivatives with high levels of BTEX is not justified from the economic point of view or from the standpoint of the environment protection.

The introduction of environmental legislation improvement for industrial producers in Serbia, notably the Integrated Pollution Prevention Control (IPPC) license, will oblige the industrial producers to provide annual report on the pollutant emissions into the environment, as well as to pay certain environment fee. Wastewater treatment plant can be a significant source of volatile organic compounds (VOCs) diffuse emissions, which are difficult to measure directly. In the near future reporting obligations might expend to benzene and other VOCs. This paper deals with gaseous emissions calculations from API separator based on the emission factors and the adequate software applications. The analyzed results show that the estimated emission values differ depending on the applied method. The VOC emissions have been estimated using US EPA and CONCAWE emissions factors. The calculated emissions range from 40 to 4500 tons/year for oil refinery WWTP of 2,000,000 m3/year. The calculations of benzene and toluene emissions have been performed using three methods: US EPA emission factors, WATER9, and Toxchem+ software. The calculated benzene and toluene emissions range from 5.5-60 and 0.7-20 tons/year, respectively. The highest emission values were obtained by the US EPA emission factors, while the lowest values were the result of Toxchem+ analysis. The sensitivity analysis of obtained results included the following parameters: flow, temperature, oil content, and the concentration of benzene and toluene in the effluent. Wide range of results indicates the need for their official interpretation for the conditions typical for Serbia, thus establishing adequate national emission factors for future utilization of the “polluter pays principle” on the VOC and benzene emissions.

Landfills are complex systems which could potentially contaminate the environment. It should be prevented by providing impermeability during the landfill design. In that aim related regulations should be followed and adequate materials that provide impermeability should be used. The first part of the paper presents review of the current regulations, interpretations, and recommendations from U.S., EU and Republic of Serbia. Knowing that the Serbian regulation should fully follow related European Directive, in analyses some inadequate formulations and terms were observed related to the Directive Annex I, 3.2. Request of the Regulation that deals with the bottom of the landfill leakage is formulated differently than in Directive as well. Mentioned problems enable some design solutions which are not among the best available techniques. In the second part the paper presents comparative analysis of possible alternatives in impermeable layer design, both for the bottom and landfill cover. Some materials like clay, CCL, GCL might not be able to satisfy prescribed requirements. The longest lifetime and the lowest coefficient of permeability, as well as excellent mechanical, chemical and thermal stability, show the mixture of sand, bentonite and polymers (PEBSM). [Projekat Ministarstva nauke Republike Srbije, br. TR 34009]

The Serbian E-PRTR register (The European Pollutant Release and Transfer Register) was established in 2007 and harmonized with PRTR protocol of Arhus convention and E-PRTR directive. In this paper, the quality of 2009 data reported to the Serbian PRTR register was analyzed. The analysis includes 37 large combustion plants with the capacity equal or greater than 50 MW. The combustion plants include power plants, heating plants and industrial energy units. The calculation is done using EMEP/EEA 2009 methodology and Tier 2 approach. The analysis obtained presents an overview of the quality of the reported data for SOx, NOx and TSP emissions for 61 combustion units e.g. emitters (stacks). The results show that all 61 emitters reported data with the deviation greater than 25%, with 55% of the emitters reporting data that differed from pollutant to pollutant in comparison to the estimated data. Out of those, 30% of the emitters reported smaller and 8% reported greater emissions than estimated emissions with 7% of the emitters not submitting any emissions data. The analysis also includes calculation of the emissions scope limit within 95% confidence interval. According to these results, it can be concluded that only 15% of the emitters have emission levels that fall within the scope limits, 47% of the emitters reported data of which two data fall within the scope limits, 28% of the emitters reported data of which only one data fall within the scope limits, 3% of the emitters had data that didn’t fall within the scope limits, and 7% did not reported any emission data. The results of the analysis can be summarized as: 1) operators in facilities do not know how to calculate emissions from their sources, and 2) the application of global emission factors can lead to considerable errors. The main reasons for significant deviation are different fuel quality, type of technical units and human error, thus national emission factors should be developed.

An empirical model for the calculation of the heat capacity of alkanes is recommended. This model was tested and compared to known models (Luria-Benson and Růžička-Domalski) using 68 sets with 1155 literature experimental heat capacity data of 39 alkanes. The obtained results indicate that the new model is slightly better of the existing models, especially near the critical point.

This paper presents empirical relations for predicting the normal freezing point of organic compounds. Nine relations were tested with 90 organic compounds. The Meyer-van der Wyk and Kreglewski-Marano-Holder models are recommended for normal alkanes, and the Constantinou-Gani and Wen-Qiang II models for all tested organic compounds.

The aldol condensation product of 1H-indan-1-one, (2E)-2-(2,3-dihydro-1H-in den-1-ylidene)-2,3-dihydro-1H-inden-1-one, subjected to Huang–Minlon reduction conditions was shown, via 1D and 2D NMR analysis, to be a mixture of (1S,1aR,6aR)-2’,3’,6,6a-tetrahydro-spiro cycloprop a indene-1(1aH),1’ 1H indene and its 1R,1aS,6aS enantiomer and not 2,3,1’,3’-tetrahydro- 1,2’ -biindenylidene as originally expected. The full NMR assignment, the coupling constants in the proton NMR, and the couplings in the HMBC and NOESY of the title compound are summarized in the Table.

Biindenylidene isomers are components of pyrolysis oils. The mass spectra were recorded and the fragmentation of the following biindenylidene isomers (E)-2,3,2’,3’-tetrahydro- [1,1’]biindenylidene (Z)-2,3,2’,3’-tetrahydro-[1,1’]biindenylidene 1,3,1’,3’-tetrahydro-[2,2’]biindenylidene and 2,3,1’,3’-tetrahydro-[1,2’]biindenylidene, as well as of spiro[1,1a,6,6a-tetrahydrocyclopropa [a]indene-1,1’-2’,3’-dihydro-1’H-indene]is discussed.

A new saturated-liquid heat capacity model is recommended. This model is tested and compared with the known polynomial and quasi-polynomial models on 39 sets with 1453 experimental heat capacity data. The obtained results indicate that the new model is better then the existing models, especially near the critical point.

In this paper a review of selected literature experimental data for saturated-liquid heat capacities was presented. Two-, three- and four-parameter polynomial correlation models are tested on those data. Obtained results lead to the conclusion that correlation quality depends on the number of parameters, and slightly on the type of models. The best two three- and four-parameter models were proposed.

The reaction of 1H-indene (indene) in the presence of Friedel-Crafts acids was studied. As expected [M. Spiteller, J. Jovanović, Fuel 78(1999)1263] there were dimers and trimers in the product mixture together with higher oligomers. Among products with double molecular weight relative to the molecular weight of indene, the structure of four compounds was determined: 6-(2’,3’-dihydro-1’H-inden-1’-yl)-1H-indene 2-(2’,3’-dihydro-1’H-inden-1’-yl)-1H-indene 1-(2’,3’-dihydro-1’H-inden-2’-yl)-1H-indene and 2,3,1’,3’-tetrahydro-[1,2’]biindenylidene. It was shown that the first one represents an indene alkylation product and that the others were obtained by bonding of the indan-1-ylium ion and indene at the position 2, followed by acid catalyzed 1,2-hydride rearrangement in the case of the third and fourth one. Considering the indene dimerization products as components of pyrolysis oils and as interesting compounds to be used as model substances for NMR, MS and X-ray analysis, the reaction, separation and isolation parameters were optimized in this study.

1H, 13Cand two dimensional NMR analyses were applied to determine the NMR parameters of 2-(2’,3’-dihydro-1’H-inden-1’-yl)-1H-indene. The chemical shifts of all the H- and C-atoms, as well as the appropriate coupling constants were determined and the complete NMR resonance assignments of the molecule are given. The predicted patterns of the four different H atoms of the two methylene groups of the indane structural element coincided completely with the complex patterns in the NMR spectra.