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The intent of this paper is to demonstrate the possibilities of transforming housing according to the contemporary needs of users in the conditions when the user is known. The methodological work starts from the thesis that housing is one of the demonstrative elements of everyday cultural patterns of a wider culture, a form of everyday behaviors but also that in daily routines of the known user lies the key for the design development direction. Agent(user) based analysis enables architecture to become a real service-not because it gives what is expected of it, but because in order to give what is expected of it, it previously studies a system of possible expectations, and then researches the possibilities of their realization, their understanding and acceptability. The paper will show the development of the concept of an ongoing design that will be realized and will discuss formal-functional preferences based on the space use analysis and the residents' habits enhanced by a moderate method of designing as the chosen methodological direction. The contribution of this paper can be seen in the demonstration of the designing process by interpreting ideas, making designing decisions grounded on facts and compromises as standard forms of behavior in procedures of practical action. In a wider sense the contribution of this paper is in demonstrating the need towards a programmatic questioning of strict differentiation's of housing spaces that were brought into question with the modern lifestyle.

Cotoneaster multiflorus is a large deciduous, ornamental shrub, suitable for landscape use. It has long arching branches and very abundant white flowers followed by scarlet-red fruit. It is low-demanding species which can grow on clay soils. As a drought tolerant species, it has potential to withstand the effect of climate change. Generative propagation of this species is difficult due to its combined embryo and seed coat dormancy. For that reason, the aim of this study was to establish quick and effective method for generative propagation of selected elite genotypes of C. multiflorus that are growing in the Belgrade area. The seeds were collected in a public green spaces in the park in Petlovo brdo, Belgrade, and after maceration, the effect of different treatments was examined. These treatments included soaking seeds in sulfuric acid at 96 % for 60 or 90 minutes, 5 months of cold stratification at 3-5oS in perlite or without substrate (naked stratification), and combinations of these treat­ments. The obtained results showed that C. multiflorus requires the combination of sulfuric acid pre­treatment and a cold stratification in perlite for germination. The seeds treated with sulfuric acid followed by 5 months of naked stratification didn’t germinate. The length of sulfuric acid treatment also influenced germination rate and better results were achieved with seeds that were soaked for 90 minutes in sulfuric acid compred to 60 minutes treatment. However, the maximum germination percentage obtained in this research did not exceed 40%, real ger­mination rate was 59%. It is necessary to perform additional research in order to improve germination.

Chinese catalpa is a medicinal and ornamental, low demanding tree which tolerates urban pollution, drought and poor soils. It should be planted more often in Serbia, and gen­erative propagation is the most suitable method for mass production of this species. The aim of this research was to investigate the effects of red and far-red light on Catalpa ovata seed germination, as well as the influence of seed storage length on germination. The seeds were collected in 2003 and 2007 from the same tree, stored for one and five years and exposed to red light (R) or far-red light (FR) before seed germination tests. After one year of storage, seed germination was high (74-82%) in a control treatment (white light conditions, 16h light and 8h dark), and the seeds did not germinate in dark conditions. Red light and a combination of red light and far red light treatments induced germination, but the obtained values varied (7 - 66%) depending on the year of seed harvesting. The seeds collected in 2003 had a higher germination percentage (51.0%) compared to the germination of seeds collected in 2007 (up to 14%) after red light treatment. The time of exposure to red light pulse (10, 15, 20 or 30 min) did not considerably affect germination rate. After 5 years of storage, germination percentage was considerably lower, reaching only 30% in white light conditions. The results obtained in this research confirmed that C. ovata seeds are photoblastic and can be stored for one year preserving a high germination rate.

The paper analyzes the levels of magnetic flux density in the apartment located above the 10/0.4 kV distribution transformer station. During the first magnetic field testing, it was concluded that in the case of the rated load of the transformers, increased values of magnetic flux density would occur in the apartment. The main sources of magnetic field in the apartment were the busbars and cable lines connecting the transformers and the 0.4 kV distribution cabinets. For that reason it is proposed to apply measures to reduce the levels of magnetic flux density, which are described in detail in the paper. After implementing the proposed measures, magnetic field testing in the apartment was repeated. The paper presents magnetic field testing results before and after the application of the measures and gives a conclusion regarding the effectiveness of the applied measures as well as regarding the compliance of the levels of magnetic flux density with the exposure limit prescribed by the current national regulations.

The paper analyses the neutrality of taxation of investment projects on the example of Serbia. The aim of the research is to confirm/reject the existence of uniformity of the tax burden on investment projects that differ regarding the asset type, industry and the source of finance. The uniformity of tax burden, that is, the absence of discrimination and distortive effects of taxation, may be considered a confirmation of the tax neutrality. To investigate neutrality of taxation the analysis employed King-Fullerton framework of calculating effective marginal tax rates. The research results show that the tax treatment of investment projects in Serbia is nondiscriminatory. Marginal effective tax rates for different types of investment projects do not vary widely; that is, there are no investment projects that have a markedly favourable (unfavourable) tax treatment compared to the other types of investment projects.

The main goal of the research in this paper is to, starting from the role that financial system has in operating of every market economy, analyze the strengths and failures of a bank-based and market-based financial system when performing basic economic functions. In order to achieve the defined goal, a qualitative research was conducted. In this sense, an innovative interpretation of the relevant scientific literature was made using descriptive and comparative analysis methods. The paper examines four approaches that represent a critical analysis of the role and importance of banks and the securities market - bankbased, market-based, financial services and legal-based approach. Emphasizing the positive role of banks, the bank-based approach highlights the comparative failures of the securities market. On the other hand, the market-based view highlights the advantages of the securities market, while at the same time emphasizing the failures of banks in performing their basic functions. However, the focus of a financial services approach is not the debate over whether a better financial system is based on banks or the securities market, but the extent, quality and availability of financial services is important. Finally, the legal-based approach, which represents addition to the financial services approach, emphasizes compliance with the provisions of financial contracts and the protection of the rights of participants in financial transactions. Accordingly, the key research findings relate to identifying assumptions that contribute to the better functioning of the financial system and to pointing out that the functional compatibility of banks and securities markets contributes to their complementarity and more efficient transfer of funds from savings towards investment entities.

The question of the status of architecture in the set relation, is always modern due to its basic feature - utility, pragmatism. Architecture, between its two elementary components of art and engineering creates a wide, though none concluded entity in whose context new meanings and interpretations are constituted. Methodologically, the paper is envisioned as a polyphone discussion regarding most frequent questions that the authors of this paper come across as lecturers. Its goal is to unlock potential context and open subjects for wider discussions. Each of the authors has seen the subject from a theoretical context in which they act. As the practices, the contexts are very different to each other.

The subject matter of the research study conducted in this paper is the interactive relationship between banks' credit activity and economic growth. In connection with that, the paper is aimed at examining the existence and direction of the cause and effect relationship between the credit activity of the banking sector and the overall economic activity in the Republic of Serbia. The quarterly data related to the period from 2003 to 2019 were collected for the purposes of the research. The share of the loans granted to enterprises in the GDP and the share of the loans granted to households in the GDP are used as the indicators of the credit activity in the study, whereas the real GDP growth rate is determined as the indicator of economic growth. Given the fact that the observed time series are of the different order of integration, the analysis is conducted within the VAR model by applying the Toda-Yamamoto procedure of the Granger causality test. The results of the research show a significant unidirectional causal relationship according to Granger, which starts from the direction of banks' credit activity towards economic growth. The results of the conducted research study can be useful to the makers of the economic policy and the creators of a strategy for the development of the national economy.

During the past twenty years, the need to reach theMoon by the private space missions has been growing. Some of the private missions are supported by Google Lunar X-prize and Space-X. In the period between 2020 and 2050 private companies will be planning landing to the Moon with their own capacity. These missions can send new geodesy and cartography data. Lunar topography modelling with new satellite and remote sensing data gives plenty of possibilities for its exploration. GIS (Geographical Information System) may be successfully to the Moon topography analysis. According to the results after GIS numerical analysis 30% of the territory of the Moon showed excellent characteristics for landing. The most useful parts of the Moon for potential landing belong to the altitude between 2,000 and 3,000 m and on the plateaus with the north-east direction of azimuth. These plateaus have an excellent inclination of 3° and azimuth of 120°. The main aim and goal of this investigation would be in better understanding of Moon topography and relief. With help of GIS numerical methods, the astronomical geodesy may be applied in better way. A potential mission to the Moon can use this topography investigation, presented maps and results.

Architectural designing is a complicated process. Oftentimes, architects, in an attempt to explain designing steps and decisions, give answers that are not a true description of their actions, often mentioning pure feeling or intuition. What can be explicitly discussed by the designers, is the least important part of the design process. What is withheld represents a methodology of designing. This paper aims to demystify the process of architectural designing through a vision on teaching and approaching designing to students that are coming into contact with it for the first time. Through a careful analysis of contemporary literature and by incorporating exact results, a methodological line of teaching designing has been tested.

The financial system is one of the most important segments of every market economy. The complexity of functioning of the financial system and the importance that it has for real business flows in the economy requires consideration of numerous factors that determine its development. Therefore, the aim of this paper is to identify the key determinants of the development of the financial system and point to their positive and/or negative effects on the performance of the financial system. Paying respect to the complexity of the stated problem, the qualitative methodology is applied, based on the dominant application of the method of analytical description. The results of the research suggest that among the most influential factors determining the development of the financial system are: political and macroeconomic environment, financial repression and liberalization, legal traditions, financial regulation and supervision and ownership structure of financial institutions.

The topic of the paper is related to the ongoing issue of exposure of the general public to high frequency electromagnetic field in the environment. The results of testings carried out in the areas of increased sensitivity located in the vicinity of base stations and radio and TV transmitters are shown in this paper. The obtained results are analyzed and compared to reference levels prescribed by the national legislation referring to the protection of the general public from nonionizing radiation.

Seeds of sweet acacia (Vachellia farnesiana (L.) Wight & Arn.) were mechanically scarified and treated with concentrated sulfuric acid in order to determine the permeability degree of the seed coat. The obtained results suggest a stronger form of seed coat dormancy that prevents potential invasiveness after introduction. The species is recommended for limited cultivation in outdoor conditions and unlimited use in interior spaces as full size or bonsai trees. [ABSTRACT FROM AUTHOR]

The topic of the paper is related to the ongoing issue of human exposure to stray electric and magnetic fields. On the example of a 400/110 kV substation a detailed presentation of power frequency electric and magnetic field testing is provided. The obtained results are analyzed and compared with reference levels prescribed by the national legislation referring to the protection of the general public from non-ionizing radiation.

Dianthus giganteiformis subsp. kladovanus is an endemic, endangered, horticulturally appealing perennial plant that can be used for the revegetation of sand dunes of the Danube region. The appropriate method for its effective production is micropropagation. For this reason, the experiments were conducted in order to establish an efficient protocol for the micropropagation of this subspecies. The sterile culture was initiated from seeds collected in situ and the germination percentage was high (88%). According to the results obtained in this study, the multiplication phase should be performed on an MS medium enriched with 0.1 mg/L BAP and 0.1 mg/L NAA. The concentration of MS salts significantly influenced rooting, and higher rooting percentages were obtained on reduced MS media (91.7 - 95%) than on MS media (73.4 - 76.7%). The addition of NAA slightly increased rooting percentage (up to 95%). Obtained microplants were successfully acclimatized (83.3%) in a substrate composed of peat and sand (1: 1; v/v). Using the protocol presented in this paper, the efficient propagation of D. giganteiformis spp. kladovanus can be achieved for rapid plant production aimed at revegetation, biodiversity protection and floricultural production of this species. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 43007]

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This study examines whether self-concept scores of deaf students vary according to age at diagnosis of deafness, the degree of deafness and the number of visits students receive from a teacher of the deaf. Thirty-seven deaf students between the ages of 12 and 18 attending inclusive educational settings in Western Australia participated in the study. The Piers-Harris Children's Self-Concept Scale, Second Edition (Piers-Harris 2) was used as a measure of self-concept. Overall, group mean self-concept scores on the Piers-Harris 2 were within the average range, with some differences between groups in relation to these. There were no significant main effects of age at diagnosis of deafness or the degree of deafness on Piers-Harris 2 domain scale and total self-concept scores. There was also no significant main effect of the number of visits by a teacher of the deaf on the Piers-Harris 2 total self-concept score. However, a significant main effect of the number of visits from a teacher of the deaf found on Piers-Harris 2 domain-scale scores was attributable to differences between the groups on the Physical Attributes and Happiness and Satisfaction scales. Specifically, students receiving one visit per week scored higher on these self-concept scales than students who received two or more visits per week. Implications and limitations of the study are discussed. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Determining high frequency electromagnetic field levels in urban areas represents a very complex task, having in mind the exponential growth of the number of sources embodied in public cellular telephony systems in the past twenty years. The main goal of this paper is a representation of a practical solution in the evaluation of measurement uncertainty for in-situ measurements in the case of spatial averaging. An example of the estimation of the uncertainty for electric field strength broadband measurements in the frequency range from 3 MHz to 18 GHz is presented.

The levels of non-ionizing radiation (electric and magnetic fields) at power frequency, which occur near 110/x kV substations are analyzed in this paper. The results of electric field strength and magnetic flux density measurements in the vicinity of three typical substations of the aforementioned voltage level are shown. With the purpose of estimating the exposure of the population to these fields, the obtained results were compared to the reference maximum levels set for increased sensitivity areas, which amount to 2 kV/m for electric field and 40 μT for magnetic flux density. The objective of the conducted analysis is to reach general conclusions on the levels of electric and magnetic fields, which may occur in the vicinity of the substations mentioned above, and evaluate their compliance with the national regulations on the population protection from non-ionizing radiation.

Balloon angioplasty fails to provide acceptable long-term results for a significant proportion of patients. An intravascular mechanical support, developed with the aim of preventing restenosis and acute closure of diseased arteries after transluminal angioplasty, was implanted in 44 patients (39 male and five female), aged from 35 to 70 years (mean 56 years) with documented restenosis of native coronary artery (41 stents) and bypass grafts (12 stents). In the group of bypass graft patients there was no local restenosis and no major complication. In patients in whom stents were placed in native coronary arteries, the complication rate was higher (two patients died after coronary bypass surgery). One patient died suddenly at home. Except for one patient, in whom a new lesion developed proximally with extension into the stent, no case of restenosis could be observed.Despite the still relatively high complication rate, we feel that stenting may present a rational approach to the unresolved problem of restenosis after coronary angioplasty. [ABSTRACT FROM PUBLISHER]

We evaluated the efficacy of flecainide acetate (given intravenously to a maximal dose of2 mg kg and then orally in a dose of 100 mg b.d. or 100 mg t.d.s.) in the conversion to sinus rhythm of 50 patients exhibiting supraventricular arrhythmias (39 with atrial fibrillation, 6 with atrial flutter, 4 with supraventricu tachycardia and onewith supraventricular tachycardia in association with the Wolff—Parkinson—White syndrome). Conversion was achieved in 36 patients (72%) (29 cases with atrial fibrillation, 4 cases with supraventricular tachycardia, 2 cases with atrial flutter and one case with Wolff—Parkinson–White syndrome), over a mean period of 7.4 ± 9 h. The patients in which conversion was achieved had arrhythmias which had been in existence for a shorter time (5.3 ± 9.8 days) than those in which conversion was not achieved (16.7 ± 26.2 days) (P<0.01). The mean dosage of flecainide used to achieve conversion was 2.5 ± 2.36 mg kg. Flecainide appears to be an effective agent for the conversion to sinus rhythm of atrial fibrillation and supraventricular tachycardias. Its efficacy in cases of atrial flutter has not yet been demonstrated. [ABSTRACT FROM PUBLISHER]

The intent of the article is to highlight the fact that Roma micro-environments contain as part of their context certain social and cultural premises, embodied in spatial forms and informal settlement construction manners that all together correspond with the principles of sustainable architecture. Methodologically, the article begins with the idea that the informal Roma settlements were built by the Romani, without an explicit professional influence and represent a quality induced by the need to functionally organize a community where everyday activities take place. Hence, the physical entities and the construction techniques in the settlements are the objects of research on knowledge and skills of a community in which the individuals are connected horizontally and hierarchically and can thus achieve positive relations inevitable for such realization. In that manner, it is possible to systematize inside a settlement a base of characters of physical structure as completed individual and group knowledge and potentials for further, acceptable advancements in that area of construction. The purpose of the paper is in drawing the attention to very concrete resources of the Roma community which should, with a gradual increase of capacities, be taken into account during the realization of the projects themselves and during the organized self-build and self-help processes as well as the process of housing condition advancement in the settlements. In a broader sense, the reduction of cost for the Romani has the potential to reduce a social distance towards them, especially in the Western Balkans where a significant portion of the population faces the same financial limits when it comes to housing advancement.

The paper presents the measured results of the resistivity values of dense ash slurry and return water mixture originating from the 'Kostolac A' thermal power plant. The four different ash slurry water mixtures with different ash concentrations are tested under laboratory conditions. The results of the tests are listed. The practical implementation of the proposed measurement method is strongly supported by the results.

The review of recent researches regarding the in vitro culture of 30 endangered Dianthus taxa is presented in this paper. Various in vitro protocols developed for selected rare and threatened Dianthus taxa are analysed in order to provide a useful synthesis of the data obtained with the main principles, techniques and recommendations for futher research and practice. The recapitulated data presented in this review can be used as a tool for the micropropagation of other endangered Dianthus taxa, enabling their propagation and obtaining a sufficient amount of plants for reintroduction. In addition, the obtained results represent the basis for ex situ conservation of the investigated taxa, especially for medium-term and long-term conservation (cryopreservation). [Projekat Ministarstva nauke Republike Srbije, br. 43007]

The aim of this study was to determine the possibility of micropropagation of the medicinal plant A. millefolium on half-strength MS medium and ex vitro rooting and acclimatization of the obtained microshoots in hydroculture in order to establish an efficient production method. Two explant types were used: basal and terminal cuttings, and better results were achieved when terminal cuttings were used. The development of shoots in the multiplication phase was successful with a regeneration percentage of 100%. Ex vitro rooting in a modified Hoagland nutrient solution was successful (83%), but the percentage of in vitro rooting on half-strength MS medium without hormones was higher (95%). However, bearing in mind that mass production of A. millefolium is more efficient when the phase of in vitro rooting is excluded, this method could be recommended for commercial propagation of this medicinal plant. It is necessary to conduct additional research in order to optimize the composition, EC and pH value of the hydroponic nutrient solution. [Projekat Ministarstva nauke Republike Srbije, br. 43007]

This paper presents an analysis of the technical-economic requirements for the construction of a solar power plant on the roof of the business building of the Electrical Engineering Institute 'Nikola Tesla' in Belgrade. Calculation of solar irradiation is performed and the conceptual design of the disposition of solar panels on the roof of the building is shown as well as their connections to the inverters. Conditions for connecting the plant to the distribution network are checked and an economic analysis of the project is performed.

In this paper are presented the analyzes of some morphometric properties, leaves area stomata density and the intensity of leaves transpiration of white poplar, Populus alba L. and canadian poplar, Populus x canadensis Moench ‘I 214’ in populations at (1) flooded (wet) and (2) unflooded (dry) habitats on the Ada Ciganlija river island during the growing season. Six trees of each species from both habitats were selected, with similar height, age and physiological condition. The morphometric analysis of the analysed poplar species show that the type of habitat did not influence tree height and trunk as well as the leaves area. However, crown width and trunk diameter were greater in the wetter habitat. It was found that the intensity of transpiration of Populus x canadensis ‘I 214’ trees had higher average values (0,73 gH2Odmˉ²hˉ¹) than white poplar (0,68 gH2Odm ˉ²hˉ¹). Transpiration of both taxa was more intensive on the drier than on the flooded habitats. By analyzing the number and size of stomata on leaves of the investigated Populus x canadensis ‘I 214’ trees, it was found that stomata are more numerous but of smaller size on the leaves from drier habitats. It could be concluded that both species could have impact on microclimate conditions by increasing air moisture content and decreasing air temperature but Canadian comparing to white poplar, slightly greater. Increasing air temperature is a consequence of evident global climate change. Through transpiration plants reduce summer air temperature indirectly, by increasing its relative humidity. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Studying climate change and its influence on the environment: impacts, adaptation and mitigation]

The study deals with the influence of growth regulators on the germination of Judas tree (Cercis siliquastrum L.) seed which is double dormant. We simultaneously tested seeds prepared in the conventional procedure: scarification + stratification and scarified seeds treated with phytohormones from the groups of gibberellins, auxin and cytokinins. The results indicate a positive effect of gibberellic acid (GA), as well as some combinations of this phytohormone with others. Recommendations for practice are to combine the conventional procedure with GA. The procedure may shorten the duration of stratification; the application of GA should follow stratification because the temperature of 4°C does not provide growth regulators activity. The study results can serve as the base for easier generative reproduction of this valuable woody ornamental species which could have a wide use in changed climate conditions. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Studying climate change and its influence on the environment: impacts, adaptation and mitigation]

In this study, the effect of concentration of indole-3-butyric acid (IBA) (powder dip), cutting type as well as the time of taking cuttings on the rooting of softwood cuttings of cornelian cherry was examined. Four types of cuttings were used: basal cuttings, terminal cuttings, basal cuttings with 2-year-old wood and terminal cuttings with 2-year-old wood. The obtained results showed that IBA concentration, cutting type and time of collecting have significant effect on rooting. The best results were obtained using 1% IBA and cuttings collected in the second term (in mid-July) had a higher rooting percentage. Terminal cuttings treated with 1% IBA (powder dip) should be used for optimum results. In that case the rooting percentage was very high (over 90%) in both terms of cuttings collection. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Istraživanje klimatskih promena na životnu sredinu: praćenje uticaja, adaptacija i ublažavanje]

The aim of this study was to investigate the effect of different concentrations of sorbitol on the development of the in vitro culture of D. serotinus in the multiplication phase. The obtained results showed that sorbitol generally had a positive effect, depending on its concentration and explant type. In addition, the presence of sorbitol affected the change of pH value of the media after autoclaving and after 25 days of in vitro culture, which could affect the availability of certain ions to plants. Therefore, the obtained results indicate that sorbitol can be used as an energy source for the in vitro culture of D. serotinus, but this should be further investigated. [Projekat Ministarstva nauke Republike Srbije, br. 43007]

The effect of the concentration of MS salts and explant type on D. serotinus rooting and acclimatization was investigated in order to optimize a protocol for the micropropagation of this species. The obtained results showed that explant type as well as the concentration of MS salts had a significant effect on rooting, and the highest rooting rate (85-86,7%) was achieved when culturing single-node cuttings and terminal buds on a half-strength MS medium supplemented with 0,5 mgL-1 NAA. Nevertheless, mean number of roots per explant was higher on the MS media (15,3-18,6) than on the half-strength MS media (11,8-13,4). The best acclimatization rate was obtained in a 4:1 mixture of peat and sand (83,3-86,7%). The explant type from which in vitro plantlets developed had no effect on the acclimatization rate. [Projekat Ministarstva nauke Republike Srbije, br. 43007]

This paper presents the soil resistivity testing results carried out at the location designated for the construction of substation 110/35/10 kV 'Zlatibor'. Testing results show that the tested soil is double-layered. Interpretation of the results of geoelectric sounding based on a mathematical model of double-layered soil shows good matching with the test results.

Propagation by cuttings is one of the most successful methods of vegetative propagation of floral crops. In addition to applications in interior decoration, ficuses belong to the group of plants that will potentially be used in green spaces of Belgrade due to global climate changes. In this paper, the possibility of rooting stimulated by adding different concentrations of the indolbytric acid phytohormone was investigated in the commonly cultivated species Ficus benjamina L. and Ficus elastica Roxb.. This is the most commonly used phytohormone in the propagation of ornamental plants due to its stability and stimulation of the rooting process, i.e. its favourable impact on the formation of adventitious roots, their size, number and weight. In this research, the rooting percent of cuttings was 100 % in F. benjamina and 77.66 % in F. elastica. It was found that the highest dose (2 %) of the phytohormone significantly increased all indicators of rooting success in F. benjamina and that the application of weaker concentrations also showed good success. The rooting of F. elastica cuttings was not successful without phytohormones, and the best results were achieved at the phytohormone concentration of 2 %, which increased the dry weight of the roots of this ficus about 4 times. It would be useful to examine higher concentrations of this phytohormone and also some combinations with other rooting stimulators, to be able to make sound recommendations on the optimal dose for the mass production of these ficuses. [Projekat Ministarstva nauke Republike Srbije, br. 43007]

Today, in vitro culture is of the great importance in both scientific investigation of under-researched plant species and plant production. In this paper, a review of development and methods of in vitro culture is presented. The main principles are given and the most commonly used methods are described. Special attention was paid to the propagation of Dianthus spp. Tissue culture of commercially important taxa is described in detail, and the review of propagation of other decorative Dianthus spp. that can be used as ornamental plants is also given. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Istraživanje klimatskih promena na životnu sredinu - praćenje uticaja, adaptacija i ublažavanje]

This paper presents an interlaboratory comparison of the measuring and calculation results of electric field strength near 35 kV overhead power line, in which three testing laboratories participated. This interlaboratory comparison was undertaken for the purpose of ensuring confidence in the quality of the test results. The measuring and calculation results were analyzed with standard method, using En number, based on which the valuation of the laboratories was performed.

The paper describes experimental research of the effects of different shields on power frequency magnetic induction mitigation. This research was performed in order to determine those materials that may be used for magnetic induction mitigation in cases where the reference level is exceeded. Using measured results, the value of the shielding factor has been calculated for all tested shields and the most efficient shields were determined.

The paper describes experimental research on the effects of different shields on power frequency electric field mitigation. This research was performed in order to determine those materials that may be used for electric field mitigation in cases where the reference level is exceeded. Using measured results, the value of the shielding factor has been calculated for all tested shields and the most efficient shields were determined.

Biological invasions are seen as a major threat to biodiversity at a global level, while the number of new invasions is increasing at an alarming rate. Raising the awareness of the public, academic world and policy makers about the dangers caused by invasive species, is essential for the creation of the support needed to implement and coordinate the policies necessary to address this problem. The aim of this study is to determine the level of local public awareness of the existence of these plant species, examine the public attitude towards alien invasive plant species and willingness to get involved in the prevention of their spreading. The survey was conducted in four nurseries on the territory of the City of Belgrade and the investigation dealt only with alien invasive woody plant species. Thirty customers were questioned in each of the four nurseries. The results show that local public is uninformed on the issue of invasive plant species. It is necessary to constantly and intensively raise their awareness of this issue, as well as the awareness of harmful consequences that may occur due to the uncontrolled spreading of alien invasive species. This refers not only to the population that visits the nurseries and buys the plants there and to those employed in plant production and selling, but also to the whole local public and decision makers.

The paper presents a comparison of measured results of magnetic field near 400 kV overhead power lines obtained by three laboratories. This interlaboratory comparison was performed to ensure confidence in the quality of the test results. The measured results were analyzed with standard methods, using En number, based on which the evaluation of the laboratories was performed.

Two methods of rooting of Zelkova softwood cuttings were analyzed: (1) quick-dip method and (2) contact method - the thin polyethylene film (20 mm) laid directly over the cuttings during the rooting process. The control for contact method was a low tunnel with a thick polyethylene film. One group of cuttings in the contact method was treated with quick-dip (IBA 2,500 μg•mL-1, carrier-ethyl alcohol) during 5 sec, and the other group was treated with water solution of IBA (50 μg•mL-1) in 24-hour treatment. The third group was control - untreated cuttings. The same groups of cuttings were also used in low tunnels. The number and length of primary and secondary roots were measured on rooted cuttings. The results of all treatments show that contact method in combination with water solution of IBA was the best with 92% of rooted cuttings. No significant differences were obtained between this treatment and quick-dip + contact method (85.3%). Rooting of cuttings under low tunnel was significantly lower. In general, contact method was better than low tunnel, disregarding the carrier used. These results recommend the almost unknown contact method in nursery propagation of Zelkova, as an alternative, non-invasive species for the conditions in Serbia.

Relative amounts of nutrients, especially nitrogen, the most abundant macro-element, and also the distribution of ammonium ions in relation to nitrate ions, in the soils of different ecosystems, are determined by many factors. The most important are: temperature, pH of substrate, accumulation of organic matter, presence of allelopathic compounds, degree of oxygenation, etc. The ability of plants to adapt to these variations influences their production of bio-mass, the rate of expansion in different habitats, and the impact on ecosystem and biodiversity. This paper analyzes the impact of different forms of nitrogen (NO3 - and NH4 +) on the growth of seedlings of invasive species Acer negundo L. and Ailanthus altissima (Mill.) Swingle. The results show that nitrogen nutrition only in the form of NH4 + ions significantly affects the reduction in shoot dry weight. Compared to the nutrition with both forms of nitrogen together, aerial parts of Ailanthus altissima were reduced by 62.5%, and leaf area by 66.7%, while Acer negundo seedlings had reduction in dry mass of aboveground part by 89.5%, root by 81.2% and leaf area by 85.8%. Nutrition with nitrate form of nitrogen led to a proportionally small, but statistically significant decrease in dry mass of aboveground parts and roots as well as leaf area of Acer negundo, while in Ailanthus altissima seedlings, it was only the mass reduction of aboveground parts that was significantly influenced, so it can be assumed that this species is more resistant to the lack of both forms of nitrogen. The fact that both species produced significantly more biomass when nitrogen was present in both forms may be important in controlling the spread of alien species, or in their potential use in phytoremediation.

Invasive species Aster lanceolatus grows on moist habitats on the whole territory of Serbia. In Belgrade, this species is recorded with a higher degree of presence at a number of localities. With the aim to investigate the community in which this species is dominant, the wide area of Serbia was researched, and 8 localities on the territory of Belgrade were chosen for the analysis of the community. Floristic structure of the community was determined by the standard Braun-Blanquet method (1964), phytogeographical analysis was performed according to Gajić (1980, 1984), and determination of life forms according to Raunkier (Ellenberg, Mueller-Dombois, 1967). pH soil analysis and electric conductivity (EC) were performed at all investigated localities. It was established that the community dominates the moist habitats of Belgrade. It is composed of 104 species and among them Aster lanceolatus Willd., Cichorium intybus L., Agropyrum repens (L.) Beauv., Calystegia sepium (L.) R. Br., Cirsium arvense (L.) Scop., Symphytum officinale L. and Rumex obtusifolius L. are the most frequent. In relation to life forms, the community has hemicriptophytes character, and in relation to phytogeography Euroasian and Middle Europaean floral elements are dominant, with a high presence of cosmopolitan and adventive floral elements. On the locialities Veliko Ratno ostrvo (island) and Makiš, EC values point to the fact that the amount of nutrient in the soil is higher than at other localities.

The Small-winged wingnut is a 12 to 20 metres tall, deciduous and fast growing tree with large substantial branches that spread as wide as the tree is tall. The 15 to 30 cm long winged fruit catkins, which turn brown in the autumn, are suspended below the branches. The species is not described by domestic authors in Serbia. The seed was introduced from Sofia (from the Arboretum of the Forestry University of Sofia, Bulgaria - Lesotehničeski universitet, Sofija), and subjected to classical stratification and naked stratification during the period of 1 and 2 months. Germination capacity varied among the treatments. The largest number of germinated seeds was observed in the shorter stratifications, (1 month) the classical (56.5%) and the naked (51.0%) with no significant difference. The values of real germination of all treatments were between 69-88%. High value of RG, compared to GC, indicated that more than 40% of the seeds were empty. However, the results of the control as well as other parameters of seed germination clearly point to the fact that practically no deep embryo dormancy was observed, but the seed is recalcitrant and microbiotic. The results indicate a non-invasive character of the species in terms of reproductive potential.

It is known that invasive plant species, as the species which most often spread and suppress the native species, form stable populations and become dominant firstly by occupying the sites of urban areas, and later on by continuing their invasion to the neighbouring suburban and rural areas. This paper presents the research of biological and ecological characters of Elaeagnus umbellata Thunb., one of the potential invasive species. The phenological observation of this species yield abundance and periodicity and the biometric analysis of fruits and seeds point to a high quality of its generative reproductive material. The analysis of seed dormancy of this species in our conditions, as the significant factor of the control of potential invasiveness, shows its double dormancy and its elimination requires combined chemical treatments and several months of stratification. The study of mechanisms of autumn olive dormancy breaking (overcoming the reproductive barrier) and seed dispersion (overcoming the dispersion barrier) is very significant for the forecast of further dispersion of this species.