Effect of cadmium stress on antioxidative enzymes during the germination of Serbian spruce [Picea omorika (Pan..) Purkynĕ]

When considering the effect of heavy metals on trees generally and on forest ecosystems especially,  importance is given to their influence on seed germination in metal polluted soil. There is insufficient data on  this subject, especially when conifers are concerned. In this work, the influence of high cadmium  concentrations on percentage germination, specific activities and isoenzyme patterns of catalase (CAT),  superoxide dismutase (SOD), and peroxidase (POD) during the germination of Serbian spruce [Picea omorika (Pan..) Purkynĕ] was studied. Cadmium chloride concentrations of up to 0.1 mM did not cause an inhibition of germination, while 1 mM concentration inhibited germination and the activities of catalase, superoxide  dismutase and peroxidase. The isoenzyme profile of catalase and superoxide dismutase did not change at high cadmium concentrations, while peroxidase expression of basic peroxidase (B5) with pI value of 9.1 increased. This isoform of POD can play an important role in the early development of Serbian spruce and its defense mechanism against heavy metals.Key words: Seed germination, catalase, peroxidase, superoxide dismutase, heavy metals

Analiza profitabilnosti hotelijerskih preduzeća u Republici Srbiji

The purpose of the research is to examine the level and trends of profitability ratios of hotel companies operating in the Republic of Serbia in the period from 2016 to 2019. The research was conducted on a sample of 100 hotel companies, where profitability was measured by the operating profit rate, the net profit rate, the rate of return on total assets and the rate of return on equity. The results of the research show that the values of the used profitability indicators have increased in 2017 compared to 2016, but decreased in 2018 and 2019. Statistical analysis found that changes in the operating profit rate and net profit rate during the observed four-year period were not statistically significant, while the decline in the value of the rate of return on total assets in 2018 compared to 2017 and the decline in the rate of return on equity in 2018 compared to 2017 and in 2019 compared to 2018 was statistically significant. The results of the research can be important for (1) the management of a company, (2) its owners, because they enable gaining an insight into the level of profitability of entrusted companies, i.e. the companies that are in the ownership, and (3) investors and creators of tourism development policy.Publishe

Axial crushing analysis of characteristics of empty and foam filled circular tubes

This paper describes experimental research of improved type of collision kinetic energy absorber. Absorber works on the principle of shrinking a foam filled tube of circular cross section. During collision, a seamless tube is passing through a special cone bush, extrusion the tube and compressing the foam. Energy is absorbed by the plastic deformation of the tube, friction between the tube and the cone bush and through deformation of the PU foam. The tubes were filled with PU foam higher density. This new type of absorber enables gradual increase of deformation resistance and greater absorption power with compact dimensions. Scaled samples have been tested in the laboratory conditions. The influence of the PU foam and different geometries on absorption characteristics, as well as the benefits of using such an absorber, are presented and discussed in this paper. The results show that the foam filled absorber has approximately 12% higher absorption power than the only extrusion absorber by itself

Korelaciona povezanost između tjelesne mase prije klanja i klaničnih randmana trupova brojlerskih pilića različitih provenijenci

The aim of this study was to determine the strength of the correlation of phenotypic correlation between body weight before slaughter and meat yield (slaughter yields) chickens two hybrids (Coob 500 and Hubbard) at different ages which is closely related to the current demand in the market of Bosnia and Herzegovina (RS) and the environment and whether consumers are interested in one - portion "chicken" or prefabricated meats. The determined data in this paper are to some extent are reaching the conclusion to which the period reasonably imaginative broiler chickens of Cobb 500, Hubbard or in relation to the fact that the hybrid show more fattening and carcass value.Cilj ovog rada је da se utvrdi jačina fenotipske korelacione povezanosti između tjelesne mase prije klanja i prinosa mesa (klanični randmani) pilića dvije provenijence (Coob 500 i Hubbard) u različitom uzrastu što je usko povezano sa trenutnom potražnjom na tržištu BiH (RS) i okoline, odnosno da li su potrošači zainteresovani za jednoporcijskim „piletom“ ili konfekcionisanim mesom. Utvrđeni pokazatelji u radu su u određenoj mjeri omogućili donošenje zaključka do kog je perioda opravdano toviti brojlerske piliće hibrida Cobb 500, odnosno Hubbard u odnosu na činjenicu koji će hibrid pokazati bolje tovne i klanične vrijednosti

ATTITUDE TOWARDS ONESELF AND OTHERS IN NON-CLINICAL POPULATION, DEPRESSED AND PARANOID EXAMINEES

Background: The theoretical concept of existential/life positions describes person’s basic beliefs about oneself and others. Most of authors on TA postulated that every person has one of four possible basic life positions: I’m OK, you’re OK; I’m not OK, you’re OK; I’m OK, you’re not OK and I’m not OK, you’re not OK. The aim of this study was the authentication of Existential positions as theoretical concepts in Transaction Analysis, and it’s potential to discriminate clinical from non-clinical examinees, and paranoid from depressive examinees within the clinical population. Subjects and methods: The research conducted was co-relational. The sample belongs to the convenience sample type, and comprised 200 examinees, 100 from the non-clinical and 100 from the clinical population of adults. Results: The results of the research confirm a statistically significant difference between the non-clinical and clinical part of the sample in the examined theoretical concept. The “I am not OK” existential position is more expressed in the clinical part of the sample. The differences between the examinees with depressive and paranoid disorders indicate that the examinees with the depressive disorder are more likely to express the “I am not OK, you are OK” and “I am not OK, you are not OK” Existential position. Conclusion: In general, we can infer that the assumptions which the research was aimed at testing received partial validation. Examinees from the clinical part of the sample have a statistically significantly higher score at the position “I am not OK”. Examinees with depressive characteristics have a more pronounced “I am not OK, you are not OK” position

Interface amorphization of two‐dimensional black phosphorus upon treatment with diazonium salts

Two-dimensional (2D) black phosphorus (BP) represents one of the most appealing 2D materials due to its electronic, optical, and chemical properties. Many strategies have been pursued to face its environmental instability, covalent functionalization being one of the most promising. However, the extremely low functionalization degrees and the limitations in proving the nature of the covalent functionalization still represent challenges in many of these sheet architectures reported to date. Here we shine light on the structural evolution of 2D-BP upon the addition of electrophilic diazonium salts. We demonstrated the absence of covalent functionalization in both the neutral and the reductive routes, observing in the latter case an unexpected interface conversion of BP to red phosphorus (RP), as characterized by Raman, 31P-MAS NMR, and X-ray photoelectron spectroscopies (XPS). Furthermore, thermogravimetric analysis coupled to gas chromatography and mass spectrometry (TG-GC-MS), as well as electron paramagnetic resonance (EPR) gave insights into the potential underlying radical mechanism, suggesting a Sandmeyer-like reaction

A hygiene report regarding slaughter process of pig and cattle carcasses for 2017 in Serbia

For the successful validation and verification of the HACCP system, a food business operator is obliged, among other duties, to have continuous microbiological data of carcasses which are followed by a certain dynamic that the subject himself prescribed. To obtain these data, it is necessary to perform systematic monitoring of indicator microorganisms. The most important meat hygiene indicators are Total Viable Counts (TVC) and Enterobacteriaceae (EC). TVC are defined as indicators of overall slaughter hygiene (equipment, environment, tools, workers), while EC are indicators of faecal contamination on carcasses. The aim of this study was to determine the microbial contamination of cattle and pig carcasses, level of hygiene of the slaughter process as well as whether variations hygiene levels were related to seasonality in Serbia during 2017. The year was divided into four quarters of three months each, while the microbiological results were classified into three levels of hygiene status (unsatisfactory, satisfactory or acceptable). The highest percentage of the results surveyed during the entire study was at a satisfactory hygiene level. Furthermore, we found there were differences in results between the quarters, which could be associated with seasonality. The best microbiological results, and so the best hygiene of carcasses, was recorded in the period April, May, June, while the worst microbiological results were observed in the period of July, August and September

Influence of Mg doping on structural, optical and photocatalytic performances of ceria nanopowders

Nanosized Mg-doped ceria powders were obtained by self-propagating room temperature reaction without using surfactants or templates. X-ray diffraction analysis and field emission scanning microscopy results showed that the doped samples are solid solutions with fluorite-type structure and spherical morphology. Raman spectra revealed an increase in the amount of oxygen vacancies with the increase of Mg concentration. This increasing results in a narrowing of the bandgap of CeO2. The photocatalytic performances of the Mg-doped ceria solid solutions were evaluated by decomposing an organic dye, crystal violet under UV irradiation. The Mg-doped ceria solid solutions exhibit significantly better photocatalytic activity than the pure CeO2 and commercial TiO2. The higher first rate constant of the Mg-doped samples demonstrated that they are much more efficient than TiO2 and CeO2 under UV light. Mg2+ dopant ions and oxygen vacancies play a significant role in the enhancement of photocatalytic performances of the Mg-doped ceria