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The objective of this research is to assess the breeding value of male individuals and calculate heritability values for body weight and body length at 12 months of age in the rainbow trout population in the Republic of Serbia. The study utilized data on the physical development of trout obtained through the Center for Fisheries and Applied Hydrobiology “Mali Dunav”, Experimental Estate “Radmilovac” of the Faculty of Agriculture, University of Belgrade (CEFAH) Breeding Program for rainbow trout in the Republic of Serbia. The fish were raised in individual tanks under tightly controlled conditions at the CEFAH, until they reached 5 months of age. At this point, the fish were marked (with PIT tags Norway) and transferred to commercial fish farms, where monitoring of their production results continued. To estimate the breeding value for body weight and body length of rainbow trout at 12 months of age, we analyzed data collected between 2016 and 2020, which included a total of 2014 individuals. The breeding values were estimated using a sire model. The mixed model incorporated fixed effects (spawning year and sex) and a random effect for the individual sire. The heritability estimate at 12 months of age was 0.44 for body weight, and 0.45 for body length. The breeding values were estimated for 107 sires, with body weight values ranging from −37.83 to +37.83 g and body length values ranging from −14.00 to +14.00 mm. The substantial variation observed within the studied rainbow trout population suggests the potential for further genetic improvement. The high heritability values confirm that further selection can be based on the phenotype. The inclusion of high-quality and validated males in breeding programs will contribute to the enhancement of production characteristics within the existing rainbow trout population in Serbia.

Ruthenium complexes have gained significant attention due to the ruthenium similarity to iron, lower toxicity, and higher anticancer effectiveness than other compounds. In this contribution, five new isonicotinate-polyethylene glycol ester ligands were synthesised and characterised by NMR and IR spectroscopies. The corresponding Ru(II) complexes were also obtained, and their structure was investigated by traditional methods. The optimisation of structures was performed at B3LYP/6-31+G(d,p) level of theory for H, C, N and O atoms and B3LYP/LanL2DZ for Ru. The intramolecular stabilisation interactions were assessed through the natural bond orbital approach. The NMR chemical shifts were predicted by the gauge independent atomic orbital method and compared to the experimental values. High correlation coefficients and low mean absolute errors between these data sets proved that the predicted structures described well the experimental ones. The theoretical and experimental IR spectra were also compared, and differences in the most notable bands were described. One of the ligands (L5) and complexes (5) showed fluorescent properties due to methylisatoic moiety. The electronic spectra of this compound were modelled by the time dependent-density functional theory method. The difference of 11 nm between the experimental and the theoretical wavelength was explained by the interactions between the solvent and the solute. Further biological and theoretical studies are advised for this series of compounds.

Effective management of the maintenance of medical equipment (ME), especially high-tech one, is one of the main issues for the quality of health care, for the provision of cost-effective health services and for saving , even in developed countries, insufficient resources. Medical equipment maintenance (EM) includes all activities related to ensuring an adequate level of service and limiting the downtime of medical equipment in a healthcare organization. Traditionally, EM is categorized as preventive maintenance (PM) and corrective maintenance (CM). The principle of PM is prediction. PM can be planned and predictive, ie. Just-In-Time (JIT) maintenance. Predictive maintenance can only be applied to new high-tech medical devices that have built-in self-testing. Planned preventive maintenance is carried out in accordance with the maintenance plan for a certain period of time. As a rule, when creating the plan, we follow the manufacturer's recommendations for preventive maintenance of ME given in the technical documentation of the ME, especially in the instructions for the maintenance of the ME. Predictive or JIT maintenance makes it possible to detect and solve the problem before problems and contingencies actually occur, and this is done on the basis of intelligent monitoring and analysis of the state of ME at the right moment, which ensures the optimal time for intervention, so that maintenance performed only when necessary. The information system for the management of the maintenance of ME in healthcare institutions would interconnect healthcare institutions and enable the fast and safe exchange of data and information related to the maintenance of ME and enable the optimal maintenance of ME in healthcare institutions, increasing the availability of this equipment, especially high-tech equipment, with significant reduction of the total cost of maintaining ME (of the order of 30%). One of the main reasons for the unsustainability of the existing approach to the maintenance of ME in the healthcare institutions of Serbia is that each healthcare institution independently takes care of the maintenance of its own ME. This approach is expensive and significantly affects high maintenance costs. This approach needs to change.

The paper examines the influence of the key determinants of success in hotel industry in the Republic of Serbia. The research was conducted for the period from 2015 to 2020 on a sample of 23 hotels. The chosen length of the observation period covers a sufficient time interval to cover all heterogeneities in the structure of the observation units, as well as their changes over time, using the dynamic panel analysis model. The adequate sample size was determined by considering the size of the population, the desired level of confidence, and the value of the allowable sampling error. The results of the research have shown that determinants such as business success from the previous period, efficiency of use of total business assets, belonging to a hotel chain, size and increasing hotel concentration index have a positive impact on success in hotel industry. On the other hand, determinants such as hotel indebtedness, operating leverage and hotel age have a negative impact on business success. Determinants such as the quality of environmental protection management and socially responsible hotel business do not have a significant impact on success in hotel industry in the Republic of Serbia.

In order for the Health Technology Management Policy at the state level to be successfully implemented, first of all, adequate personnel are necessary, and among these, biomedical engineers play an important role. Biomedical engineers (clinical engineers) work in a wide range of settings and disciplines in the health sector and play a key role in: innovation, design and development of new technologies in health care; testing, implementation and development of new diagnostic tools and medical equipment; defining safety standards for medical equipment; maintenance of (complex) medical equipment. The Ministry of Health of the Republic of Serbia labeled the biomedical engineering workforce as a "critical workforce". This critical workforce is defined as "a workforce that contributes to critical and essential elements of health technology management, especially in the domain of maintenance and replacement of (complex) medical equipment, now and in the future".

Brown trout is a common type of fish grown for consumption in open and flowing fish ponds on the rivers of Bosnia and Herzegovina. We conducted this study during three seasons (spring, summer and autumn) to obtain a complete picture of the morphological and histological characteristics of selected trout tissues. The physicochemical characteristics of the water from the Pliva River near Pljeva and the fish pond where intensive breeding of trout is carried out were analyzed. These analyses have shown that there are no major deviations in water quality and that the water in the pond is of excellent quality. A total of 90 trout were harvested during all three seasons and their morphometric characteristics were determined by analyzing ten parameters. After the dissection of all individuals, histological and stereological analysis was performed to compare the tissues of the liver, stomach, gills and muscles. These analyses showed significant differences in the histoarchitecture of selected trout tissues from the pond compared to the river. Liver tissue had altered hepatocyte shape and presence of adipocytes; stomach tissue had stronger mucosa and weaker muscle layer; gill tissue had lower respiratory lamellae; while muscle tissue had a significant presence of adipose tissue in brown trout living in the fish pond compared to those in the river. All these changes are due to the quality of commercial feed and the inability to move freely.

Serbian aquaculture is practiced in warmwater (carp) farms, coldwater (trout) farms, cage systems, recirculating aquaculture systems (RAS) and fish tanks. The total area under carp farms (ponds) registered by the Statistical Office of the Republic of Serbia (SORS) in the last fourteen years has varied between 6,192 and 8,940 ha, while under the area under trout farms was between 33,255 m2 and 81,411 m2. Total fish production over the last fourteen years varied between 5,070 tons, recorded in 2017 and 8,195 tons of market fish, recorded in 2010. Fish production is dominated by common carp and rainbow trout (about 90% of total production). In addition to these two species, several other species are cultured at carp farms, such as catfish, pikeperch, pike, silver carp, bighead carp, grass carp, Prussian carp and tench. In trout farms, additional cultured species are usually brook trout, huchen and grayling, while cultured fish species in RAS systems are sterlet and Russian sturgeon.

The aim of this study was to replace fish meal (FM) with soy protein concentrate (SPC) in carp diets. During a carp feeding trial, the replacement of FM with SPC in four diets 100% replacement (SPC100); 50% replacement (SPC50); 25% replacement (SPC25), and; 0% replacement (SPC0) had no negative effects on the feed conversion ratio or the feed efficiency ratio of the live carp. However, significant differences in the specific growth rate and condition factor were found. The data obtained showed the four different carp diets led to differences in the chemical composition of the resultant carp meat. Between dietary treatments, significant differences were seen in the level of saturated fatty acids (FAs) in carp meat (P < 0.05). The levels of monounsaturated FAs and polyunsaturated FAs in carp meat differed significantly between dietary treatments (P ˂ 0.05). Pearson's correlation coefficient indicates a statistically significant correlation between the FA composition of the diet and the resultant carp meat. It is possible to replace up to 25% of the FM with SPC. Diets SPC25 and SPC0 had no significant FA composition and had amino acid balances that, more than the other diets studied, closely met the requirements of the carp.

Numerous research papers emphasise the problems of regular Physical Education lessons. The most common problem is insufficient influence on the development of motor abilities. The goal of the present research was to study possible statistically significant differences in the transformation of motor abilities of younger school-age female students in relation to regular and additional body movements and exercises. The research was conducted during the second term of 2021/2022 school year in the primary school "Jovan Jovanović Zmaj" in Svilajnac in the form of a pedagogical experiment of longitudinal character with parallel groups. The sample of 39 female students was divided into two special sub-samples - according to the criterion of the additional body movement-exercise: the experimental group with 19 female students who had two additional exercises during one week which lasted for 90 minutes apart from regular Physical Education lessons. The additional exercises were in the form of volleyball training. There was also the control group with 20 female students who did not have any additional exercises apart from regular Physical Education lessons. 6 standardised movement tasks were applied in the evaluation of students' motor abilities. Apart from the procedures of descriptive statistics, for the processing of data the t-test was applied both to the dependent and independent samples. On the basis of the obtained results and the observed differences, it can be stated that the effects of experimental treatment in the studied variables of motor abilities influenced the improvement of motor abilities in both groups from the initial to the final evaluation. All the improvements are greater in experimental group, so that statistically significant differences between the experimental and the control group in the final evaluation were observed in five out of six studied variables and they are in favor of the experimental group. The results indicate that the application of the additional body movement - exercises outsideregular Physical Education lessons is completely justified.

Health systems are under significant pressure in many countries. Every day, with the introduction of new methods/techniques, expensive equipment of high technological value, the latest very expensive drugs... the price of health care is growing much faster than the growth of the national product and the most developed countries, despite the fact that in many countries the percentage of health expenditures in the national product is growing. Funding constraints in health systems are evident even in wealthy countries. The cost of health care is significantly influenced by: the increase in the number of the population, changes in the age structure of the population, constant demands for increasing the level of quality of health services, as well as an increase in the demand for new services. The application of international management standards in healthcare institutions and in state institutions in charge of healthcare can significantly alleviate evident problems in healthcare.

Human perception of floor vibrations and uncompromised serviceability of equipment are two most important acceptability criteria considering floor vibrations. While verification of deflection is a simple and well-known procedure in structures' design for serviceability limit state, the fulfilment of floor vibrations acceptability criteria are presented in different standards in the form of various calculation procedures. Results achieved through those calculation procedures are presented in the form of various classification of floor structures. Classification of composite floor structures due to vibrations is inconsistent considering different calculation procedures. Comparison of various calculation procedures for the definition of composite floor vibrations is presented in this paper. In addition, a parametric analysis is performed on the wide range of steel-concrete composite floor structures, through analysis of various composite floor layouts and a wide range of imposed loads values. The analysis of the relation between deflection, vertical vibrations and accelerations of steel-concrete composite floor beams is presented in this paper. The results of the parametric analysis are given through direct relation between deflections of composite beams and achieved floor class for the fulfilment of vibrations acceptability criteria due to the pedestrian walking.

The design rules for centrically compressed stainless steel equal-leg angle members are not explicitly stated in the current European standard SRPS EN 1993-1-4. This paper summarizes the results of extensive research conducted on this type of structural elements aiming to define recommendations for their design. Based on a systematic experimental investigation, a detailed numerical analysis was performed, and a database of columns' resistances were defined. Material and geometric nonlinear analysis included three key stainless steel alloys, austenitic, ferritic and duplex. The design curves for flexural and flexural-torsional buckling check have been proposed in accordance with European codified procedures.

Fish are the most commonly cultivated vertebrates in the world. They respond to stress like other vertebrates, and they can feel pain, fear and suffering. These facts are the basis for considering their welfare. The question of formal protection of fish welfare is becoming more relevant with the significant development of aquaculture in the last few decades. However, fish welfare protection is encountering difficulties. Like many terrestrial farm animals, farmed fish are often subjected to poor living conditions and cruelty. Harvesting, transport, and stunning and killing are the most significant welfare issues. This review describes some of the most important procedures that compromise animal welfare during fish farming and the negative effects these procedures have on the fish. It also gives a brief overview of the situation in Serbia in terms of research into fish welfare, public attitudes on this issue, and the state of legislation. Data presented in this paper indicate the need for more effective protection of fish welfare in the legal and executive aspects.

This paper aims to develop design recommendations for closely spaced built-up stainless steel columns, based on findings gained in performed research at the University of Belgrade. The research focuses on pin-ended built-up columns formed from two press-braked channel chords oriented back-to-back and addresses their flexural buckling capacity about the minor axis. The impact of overall and local chord slenderness, interconnection stiffness, geometric imperfections and material nonlinearity is evaluated. In order to fully exploit their structural performance, two separate approaches for the design of built-up columns with welded or bolted interconnections are defined that include different formulas for shear stiffness.

Evaluation of differences in yield and quality of grapevine is often based on the random samples of berries harvested on the same date. Due to differences in ripeness of berries from the same cluster, and among berries from different clusters of the same vine, the determined differences among examined treatments (clones, agricultural practices etc.) based on random berry samples may be over- or underestimated. The aims of this study were to determine: (1) differences among three 'Plavac mali' clones in the proportion of berries of different density classes (sugar concentration level) using the flotation method; (2) differences in berry weight and chemical composition among density classes of the same clone, and (3) differences between clones of the same density class. Significant differences were determined for all observed characteristics, among different berries density classes and clones. The results obtained indicate that berry samples used to compare different clones should be, to the greatest possible extent, at the same level of ripeness, as this significantly effects chemical composition. This can be achieved using the density separation of berries with the simple flotation method presented in this study. The presented results could be useful in the future improvement of clonal selection methodology as well as in improvement of sampling strategy for other types of researches. [ABSTRACT FROM AUTHOR]

A comprehensive examination of the solvation enthalpies and Gibbs energies of the proton and electron in twenty solvents of different polarities was carried. Eleven quantum mechanical methods were applied in conjunction with the 6-311++G(d,p) basis set and C-PCM solvation model. It was found that different methods produce consistent values for the solvation enthalpy and Gibbs energy of the proton in all solvents, while the corresponding values for the electron are mutually notably different. The fact that the Minnesota functionals often produced inconsistent solvation enthalpy and Gibbs energy values of the electron indicates their unreliable performance without the corresponding SMD solvation model, whereas other studied methods only slightly depend on solvation models. A comparison of the results of the present investigation to those obtained by employing SMD reveals that C-PCM produces slightly more negative (less positive) solvation enthalpies and Gibbs energies of the electron, and less negative values for the proton. These results are also in accord with the literature data where the IEF-PCM solvation model was used. [ABSTRACT FROM AUTHOR]

Carbon nanoparticles are a class of materials with extraordinary properties. In the past three decades, four major types of carbon nanoparticles were synthesized and investigated: fullerenes, carbon nanotubes, graphene and carbon quantum dots. One of the main properties of such materials is their hydrophobic nature. At the same time, Langmuir–Blodgett (LB) method the for deposition of thin films of hydrophobic materials provides the possibility to design thin films of different carbon-based nanoparticles with special architectures and features enabling their usage in various fields, particularly in electronics and biomedicine. In this review, the state of art of LB thin films of four types of carbon-based nanoparticles and their application in electronics and biomedicine are presented. The breakthrough in this field was finally achieved by application of carbon quantum dots soluble in solvents optimized for LB deposition. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172003]

Even though structural elements of the elliptical hollow section (EHS) have been introduced to the construction market in the past years, the rules for their design were only partially introduced into the suitable codified procedures. The aim of this paper is to present a comparative numerical analysis of behaviour of coldformed and hot-finished EHS columns exposed to flexural buckling under pure axial compression. Pinended columns of a various slenderness without lateral restrains and with incorporated geometrical imperfections are analysed. Material nonlinear behaviour is included through published experimental tensile test results, conducted in previous researches. In addition, numerical simulations of stub column behaviour are performed in order to obtain a cross-section compressive resistance. Results of the finite element analysis are compared to the design criteria defined in the draft version of Eurocode EN 1993-1-1:2015 and in North American specification for cold-formed member design AISI-S100. It is observed that North American standard provides more accurate predictions of both a crosssection resistance and a buckling column resistance. Equivalent diameter method described in Eurocode 3 led to more conservative results. According to the obtained numerical results, similar buckling behaviour is observed for both hot-finished and cold-formed columns of higher slenderness, while in the lower slenderness region, coldformed compressed members tend to lower buckling curves. Underestimation of a column buckling resistance according to Eurocode regulations is noticed for coldformed members of a higher slenderness.

Individuals with type 1 diabetes have an increased risk of premature atherosclerosis. The aim of this study was to evaluate the possible predictive significance of elevated plasma total homocysteine (tHcy), lower serum 25-hydroxy vitamin D (25(OH)D) concentrations and increased carotid intima-media thickness (CIMT) for the development of coronary atherosclerosis in patients with type 1 diabetes mellitus (T1D) and no previous history of ischemic heart disease. The study included 73 patients previously diagnosed with T1D. The patients were divided into groups with and without non-obstructive moderate coronary artery stenosis. Coronary artery stenosis was examined using coronary multidetector computed tomographic angiography (MDCTA); CIMT was measured by B-mode ultrasound. The patients with moderate stenosis had significantly higher HbA1c (p

Due to the ecological concerns and preservation of genetic resources, the characterization of genetic structure of the brown trout (Salmo trutta) was carried out on the "Braduljica" fish farm. DNA was isolated from fin clips of 10 individuals, and after that molecular PCR-RFLP methods were used for distinguishing between Atlantic and Danubian lineages based on control region of the mitochondrial DNA (CR mtDNA) and lactate dehydrogenase gene of the nuclear DNA (LDH nDNA). Based on phenotypic characteristics it was estimated that out of 10 individuals included in this study five belonged to the allochtonous Atlantic lineage and remaining five belonged to the native Danubian lineage of brown trout. However, results of molecular analyses showed a high percentage of allochthonous genes among the individuals, which confirms the hybridization between these two lineages. Also, the results showed that the selection based on the phenotype is not adequate. In order to continue with proper broodstock management, it is necessary to eliminate allochtonous individuals of the Atlantic lineage from the broodstock.

The antiradical activity of L-3,4-dihydroxyphenylalanine (L-DOPA), dihydroxyphenylacetic acid (DOPAC), homovanillic acid and tyrosine towards 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt radical (ABTS-) was investigated experimentally and theoretically by UV–Vis spectroscopy and the DFT theory. The importance of the catechol moiety for this reaction was proven due to the formation of intramolecular hydrogen bond in the formed anions and radicals. The results indicated L-DOPA and DOPAC were more potent radical scavengers than homovanillic acid and tyrosine just because of intramolecular hydrogen bond formation. Based on experimental spectra, it was proved that electron transfer led to the reduction of ABTS•-. The values of thermodynamic parameters were used to predict the preferred mechanism. The reaction rates were calculated for the electron transfer processes and it was shown that these were both kinetically and thermodynamically driven processes. Based on the reaction rate values, thermodynamic parameters, and present species, as determined by electronic spectra, it was concluded that single proton loss electron transfer (SPLET) is the dominant reaction mechanism in the investigated system. [Projects of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172040 and Grant no. 172015]

Extracurricular activities of students got legal basis by the introduction of school law in 1958, when schools got the obligation to organize extracurricular activities in order to successfully organize students’ education, broadening of social life and students’ free time. Extracurricular activities connected with physical education are: school clubs, competitions, street running, excursions, camping and other activities in nature and public manifestations. Cross country running is running on medium and long tracks in nature. This is one of the most frequent sports events in the world. In primary schools’ plan and programme cross country competitions are integral part of physical education and schools are obliged to organize cross country competitions for all primary schools students. Two cross country competitions are planned for one school year and these are spring cross country running and autumn cross country running. The organization of cross country competition especially for younger primary school students demands serious planning. Students’ age, physiological and psychophysical characteristics must be taken into consideration. In order to have nice memories from their cross country competition, students must be prepared. Preparations of students are obligatory for all school years.

Introduction: Overview of periprocedural and postprocedural (early and late) complication giving us access to determine the biological effects of treatment with covered versus uncovered metal stents in patients with irreversible jaundice malignant etiology. The Aim: The aim of study was to compare the clinical therapeutical effects of covered billiary stents versus uncovered billiary stents. Subjects and methods: We treated two groups of patients with irreversible cholestasis malignant etiology. In the first group of patients were used metal covering stents (MCS), while in the other group used metal uncovered stents (MNS). Results: We observed periprocedural complications, technical complications, and the early- to 30-day and late-to 6 months post-procedural complications such as parameters of biocompatibility of inserted endoprosthesis, i.e. biological effects on surrounding tissues. We found statistically high difference in the occurrence of bleeding and periprocedural complications in total of MNS group. In the category of early postprocedural complications, we found a statistically significant difference in the MNS groups for a hemobilia, post-stent cholangitis, stent occlusion, irritative symptoms and appetite loss, and also in the overall appearance of early postprocedural complications in MNS. In the category of late postprocedural complications statistically significant difference we found in the MNS reobstructive cholangitis, reobstruktive jaundice, irritative symptoms, loss of appetite and in full. The cause of stent dysfunction-obliteration, biliary encrustation, ingrowth, overgrowth and mucosal hyperplasia, tells us in favor of the biological effects of the insertion, point applied prosthesis and the final therapeutic effect achieved by them. Conclusions: According to our results, taking into account the parameters of biocompatibility under applicable definitions, authors can conclude that covered stents in contrast to the uncovered are meeting the criteria of almost ideal biological prostheses.

The goal of this work was to study eventual differences in preciseness of the preschoolers. The research was realized in a preschool 'Decija Radost' in Svilajnac in the first term of 2017/2018 school year. 116 preschoolers participated in this research. They were divided into two sub samples according to gender: 62 boys and 54 girls. For the evaluation of the preciseness six standardized movement tasks were used: rolling of a ball under the chair, throwing of a loop onto the post, shooting of vertical targets, shooting of a vertical square, putting the ball into the basket and shooting of the clubs. Multivariant analysis of the variance was applied, discriminative analysis, Roy's test. The values of the multivariant analysis of the variance and discriminative analysis indicate that between boys and girls in relation to all six researched motor variables there is statistically significant difference and clearly defined imit with the level of statistical significance p = 0,000. The significant statistical difference was stated by the use of Roy's test between boys and girls in relation to all six studied variables and it is in favour of the boys.