Role of local community in tourism development: Case study village Zabrega

Studies and researches on the role of a local community in tourism development of rural areas emphasize the significance of inhabitants’ attitudes about the state and perspectives of this activity. In this context, in the professional literature, the term CBT (community-based tourism) is used, which implies the involvement of local communities and planning of tourism development. The aim of the study is to determine the local population’s influence on starting an initiative for a tourist arranging of the village Zabrega in the Municipality of Paraćin, especially the sacral objects in the Crnica River Gorge. The following methods were applied: method of direct observation, analysis, synthesis, interview and survey in which the questions were of a closed and open type. Results of the research survey were analyzed in the software package for statistical processing and analysis of the data SPSS 20.00. It has been stated that the population has a positive attitude about the Society Petrus, which is the main organizer of the activities when the prosperity of the village Zabrega is in question, and that the local community is interested in engaging in the tourist activities, as demonstrated by numerous practical examples. [Projekat Ministarstva nauke Republike Srbije, br. 176017 i br. 176008

Generisanje superkontinuuma i primena u optičkim telekomunikacijama

Supercontinuum generation is a phenomenon ofsignal spectrum broadening, due to the interplay between nonlinear and dispersive effects of the nonlinear medium. This phenomenon has been the subject of numerous studies in different mediums, due to its wide range of applications in a number of fields, such as tomography, metrology, spectroscopy, biomedical optics and in the field of optical telecommunications. For the analysis and modeling of the supercontinuum characteristics, it is crucial to select a medium in which signal propagation and supercontinuum generation are performed. For the application of supercontinuum in the field of optical telecommunications, optical fibers of the specific microstructure, i.e.PCF (Photonic Crystal Fiber) fibers are used, due to the high nonlinearity and the ability to model its dispersion profile, by modeling the structure of the fiber itself. In addition to the dispersive and nonlinear characteristics of the fiber, characteristics of the supercontinuum spectrum depend on a number of input signal parameters, such as wavelength, power, shape and duration of the input pulse. These parameters significantly influence the dynamics of the supercontinuum, in terms of the formation of processes responsible for the generation of supercontinuum, such as soliton fission, dispersive waves generation, self-phase modulation, etc. On the other hand, they also affect the width of the supercontinuum output spectrum and its coherence, which is crucial for supercontinuum applications in different fields. This doctoral thesis presents the investigation of supercontinuum characteristics in PCF fibers of different dispersion profiles, for different input signal parameters. Supercontinuum generation is performed at wavelengths corresponding to the first, second and third optical windows. The processes responsible for spectrum spread in different optical windows and dispersion regimes, for different values of the input parameters, are analyzed. Supercontinuum generation in PCF fibers is numerically investigated and the process itself was modeled by the nonlinear Schrödinger equation. Also, the thesis gives an overview of the probability of distribution of extreme events, RW (Rogue Wave) waves, in supercontinuum generated in the anomalous dispersion regime. Furthermore, study was focused on determining the characteristics of the supercontinuumspectrum and its coherence in the anomalous and normal dispersive regime, in order to define the optimaldispersion regime, the type of PCF fiber and the input parameters of the signal, to obtain supercontinuum spectrum, suitable for use as a multi-wavelength optical source in WDM (Wavelength Division Multiplexing) systems

THE EFFECTS OF EXERCISE PROGRAM ON THE BALANCE OF YOUNG PEOPLE WITH INTELLECTUAL DISABILITIES

The aim of this study was to determine the effects of the 12 weeks experimental exercise program on the balance of adolescents with mild intellectual disabilities. Participants were 15 adolescents aged 15-20 years (18.18±1.54 years) with mild disturbances in intellectual functioning attending a special school „October 14th" in Nis. The program consisted of games with the balls and polygons on the basketball court. The balance ability was tested by nine tasks of the BOT-2 (Bruininks-Oseretsky Test of Motor Proficiency). The results indicate that the applied exercise program contributed to the statistically significant increase in total score of balance (p = .002), walking foreward heel-toe on the line (p = .045), standing on one leg on a line with eyes closed (p = .027) and standing on one leg on balance beam with eyes closed (p = .006). The applied exercise program had a positive influence on the balance of young people with mild intellectual disabilities. Additionally, the results can provide useful information in optimizing the training loads of students with mild intellectual disabilities throughout Physical Education classes

Korišćenje otpadnih koštica šljive kao izvora ulja i katalizatora za proizvodnju biodizela

Possibilities of using waste plum stones in biodiesel production were investigated. The plum kernels were used as a source to obtain oil by the Soxhlet extraction method, while the whole plum stones, the plum stone shells that remained after the crashing, and the plum kernel cake that remained after the oil extraction, were burned off to obtain ashes. The collected ashes were characterized by elemental composition, porosity, and base strength and tested for catalytic activity in transesterification of esterified plum kernel oil. Dominant elements were potassium, calcium, and magnesium at different contents in the three obtained ashes. The most active catalyst was the plum stone shell ash, so the effect of temperature (40, 50, and 60°C) on the reaction rate was investigated. The reaction rate constant increased with the reaction temperature with the activation energy value of 58.8 kJ mol-1. In addition, the plum stone shell ash can be reused as a catalyst after recalcination.U ovom radu istraživana je mogućnost korišćenja otpadnih koštica šljive u proizvodnji biodizela. Jezgra šljive su iskorišćena kao sirovina za dobijanje ulja primenom Soxhlet-ove metode ekstrakcije. Cele koštice, ljuske koštica šljive i pogača dobijena nakon ekstrakcije ulja iz jezgra šljive spaljeni su da bi se dobio pepeo, koji je korišćen kao katalizator. Dobijene tri vrste sakupljenog pepela su najpre okarakterisane u pogledu hemijskog sastava, poroznosti i baznosti, a zatim je testirana katalitička aktivnost u transesterifikaciji esterifikovanog ulja koštica šljive. Dominantni elementi u pepelu, kao što su kalijum, kalcijum i magnezijum, imali su različit sadržaj u sve tri vrste pepela. Najveću katalitičku aktivnost pokazao je pepeo koštica šljive, zbog čega je dalje istraživan uticaj temperature (40, 50 i 60 °C) na brzinu reakcije katalizovane ovim pepelom. Konstanta brzine reakcije povećavala se sa porastom temperature reakcije, a vrednost energije aktivacije je 58,8 kJ mol-1 . Pored toga, pepeo koštica šljive može se ponovo koristiti kao katalizator nakon rekalcinacije

The quest for excellence and a socially responsible approach in the planning process for sustainable tourism development: A case study of Slovenia

The article deals with the significance of the quest for excellence and a socially responsible approach in planning for sustainable tourism. Research and experience show that tourism organisations need to search for alternative sources and innovative elements in order to improve their competitiveness. This can be done by forming a social-relationship-network in the field of tourism, which is an important factor in creating added value and innovation. There has to be a continuous pursuit of excellence and a socially responsible approach, starting from the idea, via development, and right through to project implementation. One of the beneficial methodologies for developing and expanding a level of tourism which is sustainable and enhances the totality of local and regional environments is a multi-stakeholder approach. The second part of this paper presents a case-study of "Heritage trails through Dolenjska and Bela krajina in South East Slovenia", in which sustainable rural development1 was pursued by using an integrated approach in terms of start-up, implementation and development. This initiative was supported by and benefitted from the notion of having a core of multiple stakeholders

Theoretical study of the relationship between molecular geometry and strength of hydrogen bonds in acetylsalicylic acid

Acetylsalicylic acid is a pharmaceutical drug well-known for its anti-inflammatory and antipyretic effects, and it is commonly used for the treatment of pain and fever caused by different diseases.[1] However, it is well known that pharmaceutical properties highly depend on the geometry of chemical compounds. [2] Herein, we present a theoretical study of the relationship between molecular geometry and chemical properties for various acetylsalicylic acid structures obtained from the Cambridge Structural Database (CSD). It is significant to emphasize that studied structures were synthesized and studied under different experimental conditions, and some of them were classified as different polymorphic structures. In this work, we used quantum chemical calculations to study the influence of differences in geometries on values of calculated electrostatic potentials in critical points of selected acetylsalicylic acid molecules. The results showed that different crystal structures have significant deviations in electrostatic potential values in critical points above the ortho-Ar hydrogen atom. In addition, we studied the influence of geometry differences on the strength of C-H/O interaction between acetylsalicylic acid and water molecules. The results suggest that minor differences in the molecular geometry of acetylsalicylic acid could significantly influence the strength of C-H/O interaction. In conclusion, the geometry differences could have a crucial effect on the strength of non- covalent interactions and pharmaceutical properties of acetylsalicylic acid

DETERMING THE PRICE OF TRACTOR OPERATION DEPENDING ON THE ANNUAL ENGAGEMENT

The paper presents a calculation of fixed and variable costs for a John Deere 6110 B tractor, depending on the annual engagement of 400 and 600 working hours. Depreciation, interest, insurance, garage, repair and registration costs are calculated as fixed (ownership) costs. The costs of tractor maintenance, fuel and lubricants are presented as variable (operating) costs. The gross salary of workers and profit margin are also calculated. The value of fixed costs was calculated, regardless of the hiring of tractors during the year, 4,910 EUR. Depending on the number of working hours of tractors during the year, variable costs ranged from 14,942 EUR to 21,906 EUR. The price of tractor operation per hour was 62.67 EUR for 400 and 56.73 EUR for 600 hours of operation. With the increase in the annual engagement of tractors from 400 to 600 hours, the costs of labor per hour decreases by 5.94 EUR. In the calculation of the price of tractor work, variable costs participated with 59.61% and 64.36%, fixed costs with 19.59% and 14.42%, workers salaries with 4.95% and 5.46% and profit margin with a share of 15.85% and 15.76% for 400 and 600 hours of work, respectively. Taking into account the calculated costs, the prices of services provided by the tractor and machinery can be realistically determined, so based on that, farmers will choose whether it is more profitable for them to buy a new tractor or to rent a tractor as needed

Structural characterisation of late embryogenesis abundant proteins in Ramonda serbica Panč.

Ressurection plants are extraordinary because of their ability to withstand long periods without water, enter a state of anhydrobiosis, and fully recover upon water arrival. Ramonda serbica Panč. is a relic and endemic species that belongs to a very small group of desiccation-tolerant plants in Europe. Underlying physiological, molecular and morphological mechanisms that enable these plants to survive harsh environmental conditions have been an appealing subject of many researchers. Most of the genes responsible for this amazing ability are present in other plants, and research of those genes which could be activated in crops is growing much more attention because of the imminent crisis regarding food supplies in the near future. Key components involved in the response to dehydration in R. serbica plants were analysed through a comprehensive transcriptomic, proteomic, metabolite and photosynthetic study. Late embryogenesis abundant proteins play a significant role in the complex defence processes involved in desiccation tolerance. Defining LEAPs physicochemical characteristics and specific physiological functions may lead us to their applicability in other areas of research

Analysis of commercial supplements using a nuclear and MALDI-MS techniques

This paper presents application of a nuclear technique for the analysis of radioactivity in supplements using gas proportional counter as well as application of analytical technique Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry (MALDI-MS) in order to characterize the radioactivity contents and stability of the chemical structures for commercial supplements. Gas proportional counter enables to determination of gross alpha and gross beta activity in the environmental samples, where they are present as ultra trace elements. Also, MALDI-MS method is used, since it represents an excellent analytical technique for detecting large number of biologically important molecules, such as commercial supplements.IcETRAN 2023 : 10th Jubilee International Conference IcETRAN and 67th ETRAN Conference : program and book of abstracts; June 5-8, East Sarajevo, Bosnia and Herzegovin

Optimizacija proizvodnje biodizela kukuruznog ulja metanolizom katalizovanom pepelom kurdeljke

The use of low-cost or priceless feedstocks such as byproducts in biodiesel production results in a reduced overall process costs. The present paper reports the use of corn germs and corn cobs as byproducts from corn-based starch production in the biodiesel production by the methanolysis of the oil extracted from corn germs, catalyzed by the ash produced by combustion of corn cobs. The major aim was to optimize the methanol-to-oil molar ratio, catalyst loading, and reaction time in a batch stirred reactor with respect to the content of methyl ester fatty acids (FAME). The statistical modeling and optimization were carried out using a second-order polynomial (quadratic) model developed by the response surface methodology combined with a 33 factorial design with 3 central points. The FAME content was determined by a high-pressure liquid chromatography method. The analysis of variance showed that only the catalyst amount, the reaction time, the catalyst amount interaction with reaction time and all three quadratic terms were the significant model terms with the confidence level of 95 %. The optimum reaction conditions (the catalyst amounts of 19.8 %, the methanol-to-oil molar ratio of 9.4 mol/mol and the reaction time of 31 min) provided the FAME content of 98.1 %, which was in an excellent agreement with the predicted FAME content (98.4 %). Thus, both corn germs and corn cobs may be suitable feedstocks for biodiesel production.Upotreba jeftinih ili bezvrednih sirovina, kao što su sporedni proizvodi, u proizvodnji biodizela ima za rezultat smanjene ukupne troškove procesa. U ovom radu su prikazani rezultati upotrebe kukuruznih klica i okrunjenog kukuruznog klipa (kurdeljke, krudeljke) kao sporednih proizvoda iz proizvodnje kukuruznog skroba u proizvodnji biodizela metanolizom ulja izdvojenog iz kukuruznih klica, katalizovane pepelom dobijenim sagorevanjem kurdeljke. Glavni cilj je bila optimizacija molskog odnosa metanol-ulje, količine katalizatora i reakcionog vremena u šaržnom reaktoru sa mešanjem u odnosu na sadržaj metilestra masnih kiselina (MEMK). Statističko modelovanje i optimizacija izvršeni su korišćenjem kvadratnog modela, razvijenog metodologijom odzivne površine, u kombinaciji sa 33 faktorijelnim planom sa 3 centralne tačke. Sadržaj MEMK-a je određen metodom tečne hromatografije pod visokim pritiskom. Analiza varijanse je pokazala da su samo uticaji količine katalizatora, reakcionog vremena, interakcije količine katalizatora sa reakcionim vremenom i sva tri kvadratna člana statistički značajni sa nivoom pouzdanosti od 95 %. Pod optimalnim reakcionim uslovima (količina katalizatora 19,8 %, molski odnos metanol/ulje 9,4 mol/mol i reakciono vreme 31 min) dobijen je sadržaj MEMK-a od 98,1 %, koji se slaže sa predviđenim sadržajem MEMK-a (98,4 %). Prema tome, i kukuruzne klice i kurdeljka mogu biti pogodne sirovine za proizvodnju biodizela