Approach to identification and development of mountain tourism regions and destinations in Serbia with special reference to the Stara Planina mountain

This paper deals with theoretical-methodological issues of tourism offer planning and regulation of settlements in mountain destinations. The basic determinants of the development of mountain tourist regions destinations in EU countries, in which respectable development results have been achieved, first of all in terms of income, together with appropriately adjusted development and environmental management system, have been emphasized. The ongoing transition and structural processes in Serbia will have an impact on application of these experiences. At the same time, a basis for competitiveness of mountain regions will not be determined only by spatial capacity and geological location, but also by creative-innovative developing environment. Taking into account the spatial-functional criteria and criteria for the development and protection, the possible spatial definition of mountain tourist regions/destinations in Serbia are presented. The justifiability and positioning of tourism development projects are analyzed aiming at uniform regional development, where two segments of demand are of particularly importance, i.e. demand for mountain tourism services and for real estates in mountain centers. Furthermore, holders of tourism offer will be analyzed through a contemporary approach which may be defined as the development and noncommercial and market and commercial one. International criteria which are evaluated while selecting city/mountain destination for Winter Olympic Games are particularly analyzed. Considering experience of countries with higher level of development of mountain regions, the main starting point for positioning projects for sustainable development of tourist destinations are defined by specifying them according to specific local and regional conditions. A rational model for spatial organization of tourism offer is shown on the example of the Stara Planina tourist region

The effect of negative mood intensity on autobiographical recall: Evidence for the underlying role of affect in mood congruence effect

In the present study we test the hypothesis that affective state underlies the effect of mood congruence in autobiographical recall. Forty-five participants were subjected to negative and neutral mood inductions, and then asked to recall one personal memory. We also introduced another negative mood condition in which participants were exposed to the same mood inducing material (i.e., pictures), but were supposed to feel a less intense affective state. We replicated the congruence effect between the mood inductions and the valence of the participants’ recalled memories. Furthermore, mood congruence was influenced by the intensity of negative mood inductions. Although the participants in negative mood conditions were exposed to the same semantic material, the recalled memories were more negative in standard (strong) than in moderate negative mood condition. Furthermore, this effect was mediated by mood, as measured by the self-report questionnaire. The results suggest that affect influences the mood congruence effect in a way that cannot be explained by semantic priming alone

Phylogeographic study of brown trout from Serbia, based on mitochondrial DNA control region analysis

In order to illuminate the phylogeography of brown trout (Salmo trutta) populations in the Balkan state of Serbia, the 561 bp 5'-end of mtDNA control region of 101 individuals originating from upland tributaries of the Danubian, Aegean and Adriatic drainages were sequenced and compared to corresponding brown trout sequences obtained in previous studies. Among 15 haplotypes found, 14 were considered native, representing the Danubian and Adriatic lineages of the brown trout, while one haplotype (ATcs1), found only in two individuals originating from two stocked rivers, corresponded to the Atlantic lineage and was considered introduced. Native haplotypes exhibited a strong geographic pattern of distribution: the Danubian haplotypes were strictly confined to the Danubian drainage, while the Adriatic haplotypes dominated in the Aegean and Adriatic drainages; most of the total molecular variance (69%) was attributed to differences among the drainages. Phylogenetic reconstruction, supplemented with seven haplotypes newly described in this study, suggested a sister position of the Atlantic-Danubian and Adriatic-Mediterranean-marmoratus ("southern") phylogenetic group, and pointed to the existence of a distinct clade, detected within the "southern" group. The data obtained confirmed our expectation of the existence of high genetic diversity in Balkan trout populations, and we recommend more widespread surveys covering trout stocks from the region

Procena ekološkog rizika u funkciji zaštite životne sredine

This paper proposes an appropriate methodology for ecological risk assessment. The methodology has been applied in the region of Boka Kotorska Bay (Bay), Montenegro. The emphasis of the research is on the analysis of the impact of various stressors on the ecological components of Bay. The consequences of that impact can be seen in an increased level of eutrophication of water environment, mostly through the influence of nitrogen and its compounds. The actual research at/about the region of Boka Kotorska Bay was performed in the period of 2008. The study emphasized the importance of the acquisition, processing and analysis of various ecologically related data for more efficient monitoring and management of the environment. The suggested methodology of the ecological risk assessment is, therefore, a remarkable scientific and expert contribution in the area of environmental protection in our country and in general.U radu je predstavljena primena metodologije procene ekološkog rizika. Metodologija je primenjena na primeru Bokokotorskog zaliva (Zaliv). Istraživanjem je razmatrana procena uticaja većeg broja stresora na ekološke komponente Zaliva. Posledice ovih uticaja ispoljene su kroz povećan stepen eutrofikacije vodene sredine i dovode se u vezu sa koncentracijom azotnih jedinjenja (nitrata i nitrita) Konkretna merenja vršena su u 2008. godini. Istraživanjem je posebno ukazano na značaj razvoja sistema prikupljanja i obrade ekoloških i drugih informacija radi efikasnijeg upravljanja životnom sredinom datog prostora. Primenjena metodologija procene ekološkog rizika trebalo bi da u naučnom i stručnom pogledu predstavlja doprinos u oblasti zaštite životne sredine,kako kod nas, tako i u svetu

Genetic characterization of broodstock brown trout from Bled fish-farm, Slovenia

Background and Purpose: Due to environmental and economic concerns, Bled fish-farm is interested in establishing broodstocks of native brown trout (Salmo trutta L.). Progeny would be reared and released into rivers managed by the Fishing Club Bled. In this study was performed genetic characterization of broodstock from Bled fish-farm in order to assess hybridization of native brown trout of Danubian phylogeographic lineage with trout of the allochtonous Atlantic lineage. Material and Methods: DNA was isolated from fin clips of 20 males and 20 females from broodstock. PCR-RFLP technique was used for distinguishing between Atlantic and Danubian lineages on the basis of control region of the mitochondrialDNA(CRmtDNA) and lactate dehydrogenase gene (LDH). Results: Results show a high percentage of allochthonous genetic markers especially among females and confirm hybridization between native and introduced brown trout. Conclusions: Because of low percentage of native trout markers, Bled fish-farm decided to continue with collecting and genotyping fish to establish a broodstock with higher percentage of genetic markers characteristic for native trout of Danubian lineage

Tribological Assessment of Aluminum Cylinder Material for Piston Compressors in Trucks and Buses Brake Systems

Applying new technologies to reduce friction and wear in vehicles and equipment can minimize mechanical losses. This reduces power loss in internal combustion engines and reduces fuel consumption and emissions. Consumption of fuel energy can be reduced by the use of light metals, for example aluminum alloy, to produce vehicles and their aggregates and parts. In this case, the problem is poor tribological properties of those light weight metals, as well as the lower strength compared to the cast iron construction. For tribology research purposes, the contact surface of the aluminum cylinder of an experimental piston air compressor is reinforced with inserts of cast iron. The results of tribology research of the composite material are presented in the paper, explaining how parameters such as the sliding speed, contact time and contact area influence friction and wear of the material in relative tribological contacts, under constant normal force. The test procedures were performed on the ball-on-plate CSM® nanotribometer, in linear reciprocating sliding conditions with no lubricant. Material composition of the samples was determined using the Energy-Dispersive Spectroscopy. All measurements were realized at the Faculty of Engineering, University of Kragujevac

Correlation between Emission and Combustion Characteristics with the Compression Ratio and Fuel Injection Timing in Tribologically Optimized Diesel Engine

Diesel engines are economical thanks to their combustion process characteristics, which is why they have a high noise emission level as well as exhaust emissions of nitrogen oxide and particulate matters. By continuously changing the value of compression ratio, it is possible to control the power and emissions. Implementation of variable compression ratio has many benefits, such as being able to work with different types of fuel. In this way, it is possible to optimize the combustion process for operation with minimum fuel consumption and emission generation, so that diesel engines can be applied to the framework of future hybrid vehicle concepts, and so forth. As far as the crucial objective of the manuscript is concerned, experimental diesel engine investigation was performed on a roller test-bench by using zero-dimensional computer model (specifically AVL IndiCom Indicate Software). Engine indication was executed with the factory compression ratio value and with three lower values. During our examination, the change in the compression ratio value was achieved by changing the volume of a combustion chamber at a piston-bowl. The results of laboratory research on the experimental engine are presented in the paper when discussing a series of specific parameters (characteristics), such as compression ratio, fuel injection timing, engine speed, as well as load influence on combustion process and exhaust emissions

Određivanje genetičke strukture potočne pastrmke (Salmo trutta) iz ribnjaka "Braduljica", Srbija

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.U cilju zaštite ţivotne sredine i genetiĉkih resursa potoĉne pastrmke (Salmo trutta) u radu je ispitivana genetiĉka struktura ove vrste na ribnjaku ―Braduljica‖ u blizini Ivanjice. DNK je izolovana iz odseĉaka peraja 10 jedinki, a nakon toga molekularne PCR-RFLP metode su korišćene za razlikovanje izmeĊu atlantske i dunavske linije na bazi kontrolnog regiona mitohondrijalne DNK (KR mtDNK) i jedarnog gena za laktat dehidrogenazu (LDH nDNK). Na osnovu fenotipskih karakteristika procenjeno je da je pet jedinki pripadalo alohtonoj atlantskoj liniji, a preostalih pet autohtonoj dunavskoj liniji potoĉne pastrmke. MeĊutim, rezultati molekularnih analiza pokazali su prisustvo visokog procenta alohtonih gena u analiziranom uzorku, što potvrĊuje hibridizaciju izmeĊu ove dve linije. TakoĊe, rezultati ukazuju na to da selekcija na osnovu fenotipa nije adekvatna. Kako bi ribnjak nastavio da se bavi gajenjem potoĉne pastrmke za potrebe poribljavanja okolnih reka, neophodno je da se eliminišu jedinke atlantske linije iz matiĉnog fonda

Hucho hucho (Linnaeus, 1758): last natural viable population in the Eastern Carpathians - conservation elements

There is great variation in the conservation status of the last habitats with long-term natural viable populations of the salmon species Hucho hucho in Maramureş Mountains Nature Park, Eastern Carpathians (Romania). According to the specific guidelines for Natura 2000, 42.11% are in good conservation status, 31.57% are of average status, and 26.32% are in a partially degraded condition. In this study area, 6 main risk elements were identified related to human impact on the environment: poaching, minor riverbed morphodynamic changes, liquid and solid natural flow disruption, habitat fragmentation leading to isolation of fish populations, organic and mining pollution, and destruction of riparian tree and shrub vegetation. All of them have contributed to the decrease of H. hucho distribution in the study area to about 50% of the previous local range. Individuals of this species were recorded in only 21 of the 370 sampling stations

Solving the Problem of Friction and Wear in Auxiliary Devices of Internal Combustion Engines on the Example of Reciprocating Air Compressor for Vehicles

Using vehicles and other mobile systems to transport passengers and goods, approximately 25% of Europe\u27s greenhouse gases are generated. At the same time, many research papers, published by researchers and students, promote the use of electric vehicles as zero-emission vehicles. Given that, more broadly, the emission of electric vehicles is higher, especially in countries where electricity is obtained by burning coal, the use of internal-combustion engines is still dominant. There are other reasons for using an internal-combustion engine, such as already developed pumping station infrastructure, which is not the case when recharging electric vehicles. Improvements in engine design contribute to meet the regulations relating to the fuel consumption and toxic gas emissions. This refers to the use of alternative fuels, improving the combustion process, and increasing efficiency (efficiency coefficient) by reducing losses. The research is focused on the problem of friction and wear in internal combustion engines and reciprocating air compressors, as auxiliary devices on engines. For that purpose, construction of the reciprocating air compressor in motor vehicles was redesigned. The paper presents the characteristic test results of material used to strengthen liner of the aluminum cylinder. Specifically, a method for testing the performance characteristics of a single-cylinder reciprocating compressor inside of an experimental installation for compressed air supply has also been proposed