Workplace bullying in Serbia: The relation of self-labeling and behavioral experience with job-related behaviors

Workplace bullying has been identified as a widespread problem in contemporary organizational research. The aim of the paper was to acquire theoretically based and comparable findings about workplace bullying in Serbia: to explore the behavioral experience and self-labeling approaches (applying the Negative Acts Questionnaire - Revised, NAQ-R) and their relationship with job-related behaviors. The sample comprised 1,998 employees. Prevalence rates of workplace bullying based on self-labeling and behavior experience approaches overlap significantly (70% of employees operationally identified as bullied had also labeled themselves as bullied). Both the self-labeling and behavioral experience approach showed significant correlations with job-related behaviors (perceived threat to a total job, absenteeism, intention to leave, and perceived productivity). Previously bullied, presently bullied and non-bullied employees differed significantly on all four job-related behaviors, with large effect size for the intention to leave and medium effect size for the perceived threat to a total job. The findings support combining self-labeling and behavioral experience approaches in workplace bullying research. [Projekat Ministarstva nauke Republike Srbije, br. 179018

It was great, they were all young! Is there ageism in students’ reflections on professional internship?

Noting the tendency of students of work and organizational psychology to choose internships among a smaller number of hosting organizations paired with satisfaction with completed internship expressed by the sentence ‘It was great, they were all young’, we performed qualitative content analysis of students’ reflections on age in the context of internship attractiveness. The materials for the analysis were 1) Fifty internship reports and 2) Discussions with students. There was no explicit ageism in students’ reports. Students were equally satisfied with mentors from more and less popular organizations. Four categories related to attractiveness of internship hosting organizations emerged: organizational culture, organizational climate, working conditions and mentors’ work. As in the case of more attractive organizations they point to ‘younger’ organizations, as a factor of their attractiveness, they could be discussed as ‘clear manifestations of ageism’, but also they could be regarded as ‘younger generation centeredness’, and partly a form of ‘covert ageism’. Reflections could also be interpreted as a consequence of students’ professional insecurity, need for peer support, ease of communicating with peers and those of similar age. Psychological distance from older generations of colleagues and mentors at work can both be the source of covert and overt ageism. In order to enable students to fully utilize the benefits of internship for their professional development, it is important to work on recognizing and preventing ageism and overcoming generational distances

Histochemical observation and the analysis of biochemical bone regeneration markers in treatment of an osteoporotic rat bone with Ca/Co-HAp nanoparticles

One of the prerequisites for a good prosthetic rehabilitation is well preserved bone tissue. However, osteoporosis as a modern age disease often compromises a good dental treatment. Oral implantology offers a solution through the use of various biomaterials. Most researchers focus on the synthesis of the nanomaterials with magnetic and paramagnetic properties. The aim of this study is to examine the role of Ca / Co-HAp nanoparticles in the regeneration of the osteoporotic alveolar bone in experimental animals by analyzing the biochemical blood markers (ALP, Ca, Mg, and P) and through histochemical analysis. The research was carried out on female Westar rats, aged 6-8 weeks. The obtained results for the biochemical blood markers showed statistically significant rise. Histological analysis revealed high level reparatory skills of the biocomposite implanted in the bone defect as early as in the 6th week of the experiment as well as an increased alkaline phosphatase activity in the mineralized tissues. The implantation of the biomaterials facilitates osteogenesis, justifying their use in the accelerated regeneration treatment of the osteoporotic alveolar bone

Evaluation compensation of an osteoporotic rat bone with Ca/Co-HAp nanoparticles

This study examined the role of Ca / Co-HAp nanoparticles on time distance in regeneration of osteoporotic alveolar bone in rats by biochemical blood markers analysis (ALP, Ca, Mg, P) and through histochemical analysis. The research was carried out on female Westar rats, aged 6-8 weeks. The obtained results for the biochemical blood markers showed statistically significant rise. Histological analysis revealed high level reparatory skills of the biocomposite implanted in the bone defect as early as in the mineralized tissues. It can be concluded that Ca/Co-HAp stimulates the regeneration of osteoporotic alveolar bone in tested animals as confirmed by the increased levels of biochemical blood markers and through histochemical analysis. Therefore, it can be concluded that Ca/Co-HAp nanocomposite should be choise material in the osteoconstructive processes in the future

Testing the antimicrobial activity of hydroxyapatite nanoparticles in vitro

Antimicrobial materials based on hydroxyapatite are very attractive for wide application in medicine and stomatology. The goal of this work was to test antimicrobial activity of hydroxyapatite nanoparticles Co/Ca- hydroxyapatite and biphasic calcium phosphate/ poly (lactide-co-glycolide) composite biomaterial. Antimicrobial activity of the samples was tested using dilution method and disk diffusion. The results of antimicrobial tests were obtained by determining the reduction percentage the number of bacteria in physiological solution where bacteria cells were exposed to the samples. It can be concluded that synthesized HAp biomaterials have satisfactory antimicrobial activity against tested bacteria strains

Aktivnost alkalne fosfataze u kosti nakon implantacije nanočestičnog kalcijum-kobalt hidroksiapatita

Istraživanje je sprovedeno sa ciljem da se dokaže aktivnost alkalne fosfataze, lokalizovane u dekalcifikovanoj kosti, uzete sa leve strane mandibule pacova, u kojoj je arteficijalno napravljen defekt i implantiran nano kalcijum-kobalt hidroksiapatit. Studija je obuhvatila 48 životinja, starosti 6-8 nedelja. Posle šest i dvadeset četiri nedelje od implantacije biomaterijala, uzeti su uzorci za histohemijsku analizu i fiksirani u PLP fiksativu. Zatim su dekalcifikovani, ukalupljeni u parafinski blok i obrađivani za svetlosno-mikroskopska ispitivanja i histohemijsko dokazivanje aktivnosti alkalne fosfataze. Histološka analiza je pokazala visok stepen reparatornih sposobnosti ugrađenog biokompozita u koštani defekat. Histohemijskom analizom je dokazana aktivnost alkalne fosfataze u mineralizovanom tkivu

The effect of herbal extract Foeniculum vulgare Mill. solution on the mechanical and wetting properties of heat polymerized denture base resin

Introduction. Commercially used chemical dental cleansers adversely affect mechanical properties of denture. Therefore, there is a need for finding an alternative which will not change the surface properties of material. Aim. This paper studied the effect of the herbal extract (Foeniculum vulgare Mill.) solution on the wetting and mechanical properties of heat-polymerized denture base resin compared to the same properties of the same resin in the native state (in air) and exposed only to aqueous environment. Material and methods. Rectangular shape of heat polymerized acrylic resin (15 mm x 15 mm x 3 mm) were prepared and divided into: (i) sample continuously exposed to air - AIR; (ii) sample continuously exposed to distilled water - DW; and (iii) sample exposed to 10% solution of the fennel leaves extract - PES. Wetting properties were measured by sessile drop method, whereas mechanical properties were analyzed by nanoindentation method. Results. Results showed that samples AIR had the lowest ΘC value 64.5±2.3 °, while the other two samples DW and PES had similar ΘC values (75.4±3.3 °, 75.7±4.7 °, respectively). Furthermore, there was no statistically significant difference in hardness coefficient, while Young's modulus showed a significant difference (p < 0.005) only between the samples AIR and DW. Conclusion. The obtained values confirmed that fennel extract can be used as successful and efficient cleanser, without degradation of denture surface

Profili masnih kiselina i antioksidativna svojstva sirovih i sušenih oraha

Background: Walnuts consumption produces beneficial effects on human health. Health-promoting benefits are dedicated to its desirable fatty acid profile and high content of antioxidants. Heat treatment of walnuts may alter their fatty acid composition and antioxidant capacity. Aim: In general the aim of this work was to compare fatty acids profiles and antioxidative properties of raw and dried walnuts at 60 °C for 12 hours. Methodology and results: FA profiles were analyzed using gas chromatography. Antioxidative capacities of walnut samples were determined by DPPH and ABTS tests. There were no significant differences in fatty acid profiles comparing dried and raw walnuts. The most abundant fatty acid was linoleic with mean content of 61.38 ± 1.11% in raw and 62.40 ± 0.99% in dried walnuts. Walnuts oil contained 10.64 ± 0.46% and 10.49 ± 0.81% of a-linolenic acid (ALA) in raw and dried walnuts, respectively. Antioxidative capacity of methanolic extracts showed no difference comparing raw and dried walnut by DPPH and ABTS test. Heat treatment at 60 °C for 12h induced no change in fatty acid profiles of walnuts and led to minor decrease in antioxidative capacity measured only by ABTS test. Conclusion: We suggest that drying process in our experiment did not decreased nutritional capacity which is mostly mediated by conservation of fatty acids content in walnuts.Dijetarni unos oraha povezuje se sa brojnim pozitivnim efektima na zdravlje. Svoj efekat na zdravlje orasi ostvaruju zahvaljujući povoljnom masnokiselinskom sastavu i visokom sadržaju antioksidanasa. Zagrevanje oraha moglo bi dovesti do promena u masnokiselinskom sastavu i uticati na antioksidativni kapacitet. Cilj ovog rada bio je da se uporede masnokiselinski profili i antioksidativni status svežih i oraha sušenih na 60 °C u trajanju od 12 sati. Masnokiselinski sastav analiziran je gasnom hromatografijom. Antioksidativni kapaciteti uzoraka oraha odreðivani su DPPH i ABTS testovima. Utvrðeno je da nije bilo promena u masnokiselinskim profilima posle sušenja oraha na 60 °C u trajanju od 12 sati. Najzastupljenija masna kiselina bila je linolna sa sadržajem od 61.38 ± 1.11% u sirovim i 62.40 ± 0.99% kod sušenih oraha. Ulje oraha sadržalo je 10.64 ± 0.46% i 10.49 ± 0.81% a-linolenske kiseline (ALA) u svežim i sušenim orasima, respektivno. DPPH testom nije utvrđeno da postoje razlike u antioksidativnom potencijalu metanolnih ekstrakata oraha sušenih u odnosu na sveže kao ni sa ABTS testom. Naš eksperimet je pokazao da proces sušenja oraha nije smanjio njihov nutritivni kapacitet što je verovatno posredovano očuvanjem sadržaja masnih kiselina

In vitro evaluation of antimicrobial activity of nano composite biomaterials based on hydroxyapatite

Antimicrobial materials based on hydroxyapatite are potentially attractive in a wide variety of medical and stomatological applications. The objective of this paper is to examine antimicrobic activity of cobalt-substituted calcium hydroxyapatite nanopowders and biphased calciumphosphate/ poli-lactide-co-glicolide. The antimicrobial effects of these substances (powders) against two pathogen bacterial strains- Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923) were tested by disc diffusion method and quantitative antimicrobial test in liquid medium. It was noted that the inhibition zone of the bacterial cells S. aureus around the sample of the Ca/Co- HAp, was a lot bigger compared to the inhibition zone of bacterial cells E. coli around the sample of the mentioned biomaterial, which means that this material has bigger antimicrobic activity on S. aureus, in relation to E. coli. Quantitative antimicrobial test in liquid medium demonstrate that cobalt-substituted calcium hydroxyapatite samples show viable cells reduction of both tested microorganisms. It may be concluded that nanoparticles of cobalt-substituted calcium hydoxyapatite nano-powders has a satisfactory antimicrobic activity according to the tested bacteria strain

Kalcijum/kobalt hidroksiapatit nanočestice u regeneraciji osteoporotične kosti donje vilice

Osteoporoza kao bolest savremene civilizacije postaje sve aktuelnija u stomatologiji. Jedan od trendova u nalaženju rešenja je u oralnoj implantologiji kroz primenu biomaterijala sa magnetnim česticama. U ovoj studiji ispitivan je uticaj nanočestica Ca/Co-HAp na regeneraciju osteoporotične alveolarne kosti eksperimentalnih životinja analizom biohemijskih markera krvi (Ca, Mg, P). Istraživanje je sprovedeno na 48 Wistar pacovima, starosti 6-8 nedelja kojima je implantiran biometrijal u osteoprotičnoj alveolarnoj kosti. Dobri rezultati regeneracije osteoporotičnog tkiva su postignuti 6 nedelja nakon implantacije nanočestica. Biohemijski parametri koštane sinteze su u statistički značajnom porastu. Implantacija biomaterijala omogućava brzo formiranje nove kosti što ih čini materijalima izbora za ubrzanu regeneraciju kosti