37 research outputs found
Nanoindentation of Za-27 Alloy Based Nanocomposites Reinforced with Al2O3 Particles
Nanoindentation has been widely used for material mechanical characterization. In this study, nanocompozite of ZA-27 alloy matrix reinforced with different volume fractions of nanometric Al2O3 ceramic particles ranging from 0 to 5 %, were produces using compocasting technique. Nanoindentation tests were performed using Berkovich three sided diamond pyramid, with maximum load of 100 mN and maximum load holding time of 15 s. Indentation imprints were investigated using optical and atomic force microscopy (AFM). Average particle size was 20-30 nm. Nanoindentation tests showed that nanocomposites have higher values of hardness and lower values of elastic modulus in comparison to the ZA-27 matrix alloy. Obtained results have different values in comparison to the theoretical investigations
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Acting the part: Emotional intelligence and job satisfaction as predictors of emotional labor in travel agencies
Employees of retail travel agencies in sales roles have direct contact with tourists, which, in the case of poor customer service, can be extremely negative for businesses. Because of this, it is important to understand how employees manage their emotions in a way that can help them to remain satisfied with their work and avoid burnout. However, job satisfaction, emotional intelligence and emotional labor have not previously been studied in one model in the field of tourism and hospitality. Herein the mediating role of emotional intelligence in the relationship between job satisfaction and emotional labor in travel agencies is analysed, as well as job satisfaction as an antecedent of emotional labor in this sector. Data were collected from 160 employees of 45 travel agencies in the Serbian cities of Belgrade and Novi Sad. The results show that employee’s emotional intelligence mediates the positive relationship between job satisfaction and emotional labor. Increasing employees’ emotional intelligence through training and development and actively recruiting employees with high emotional intelligence will reduce emotional exhaustion and improve customer satisfaction for retail travel agencies
A Mumps Outbreak in Vojvodina, Serbia, in 2012 Underlines the Need for Additional Vaccination Opportunities for Young Adults
In 2012, mumps was introduced from Bosnia and Herzegovina to Vojvodina, causing an outbreak with 335 reported cases. The present manuscript analyses the epidemiological and laboratory characteristics of this outbreak, identifies its main causes and suggests potential future preventive measures. Sera of 133 patients were tested for mumps-specific antibodies by ELISA and 15 nose/throat swabs were investigated for mumps virus RNA by RT-PCR. IgG antibodies were found in 127 patients (95.5%). Mumps infection was laboratory-confirmed in 53 patients, including 44 IgM and 9 PCR positive cases. All other 282 cases were classified as epidemiologically-confirmed. More than half of the patients (n = 181, 54%) were 20-29 years old, followed by the 15-19 age bracket (n = 95, 28.4%). Twice as many males as females were affected (67% versus 33%). Disease complications were reported in 13 cases (3.9%), including 9 patients with orchitis and 4 with pancreatitis. According to medical records or anamnestic data, 190 patients (56.7%) were immunized with two doses and 35 (10.4%) with one dose of mumps-containing vaccine. The Serbian sequences corresponded to a minor genotype G variant detected during the 2011/2012 mumps outbreak in Bosnia and Herzegovina. Vaccine failures, the initial one-dose immunization policy and a vaccine shortage between 1999 and 2002 contributed to the outbreak. Additional vaccination opportunities should be offered to young adults during transition periods in their life trajectories
New Hybrid Properties of TiO2 Nanoparticles Surface Modified With Catecholate Type Ligands
Surface modification of nanocrystalline TiO2 particles (45 Å) with bidentate benzene derivatives (catechol, pyrogallol, and gallic acid) was found to alter optical properties of nanoparticles. The formation of the inner-sphere charge–transfer complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites. The binding structures were investigated by using FTIR spectroscopy. The investigated ligands have the optimal geometry for chelating surface Ti atoms, resulting in ring coordination complexes (catecholate type of binuclear bidentate binding–bridging) thus restoring in six-coordinated octahedral geometry of surface Ti atoms. From the Benesi–Hildebrand plot, the stability constants at pH 2 of the order 103 M−1 have been determined
Influence of plasma spraying parameters on properties of thermal barrier coatings
The aim of the present study is to investigate the influence of plasma spay deposition parameters on various properties of two standard thermal barrier coating (TBC) systems deposited on the steel substrate. Two TBC systems were investigated: NiCr-Al-Co-Y2O3/ZrO2-Y2O3 and NiCr-Al-Co-Y2O3/ZrO2-CeO2-Y2O3. Powders were deposited by atmospheric plasma spraying (APS) with two variable parameters. The first variable was substrate temperature (21-23 and 160-180 degrees C), and the second variable was transverse speed of the spraying gun (250 and 500 mm s(-1)), i.e. coating thickness per one pass of the spraying gun. The quality assessments of TBC systems were made on the base of their microstructure, microhardness, tensile bond strength and thermal cyclic behaviour (thermal insulation properties and thermal cycling fatigue). Analysis of the results showed great influence of plasma spray deposition parameters on the quality of obtained TBCs
Prognostic significance of Gleason score 7 (3+4) and Gleason score 7 (4+3) in prostatic adenocarcinoma in relation to clinical stage, androgen tissue status and degree of neuroendocrine differentiation
Prognosis and choice of treatment of adenocarcinoma of the prostate (ADCP) directly depend on the numerous of predictive factors, among which the most important are summary histological tumor grade (Gleason score, which is the sum of the first and second dominant histological grade) and clinical stage. According to recent research these factors include androgen tissue status and degree of neuroendocrine differentiation. The importance of the first and second dominant histological grade becomes particularly important in ADCP Gleason score 7. Tumors with worse prognosis considered to be ADCP of higher Gleason score, the advanced clinical stage, androgen independent tumors and tumors that show a higher degree of neuroendocrine differentiation. The aim of the study was to determine the predictive significance of ADCP Gleason score 7 (3+4) and ADCP Gleason score 7 (4+3) in relation to clinical stage, androgen tissue status and degree of focal neuroendocrine differentiation. The study included 33 ADCP of Gleason score 7,26 (78.79%) ADCP 7 (3+4) and 7 (21.21%) ADCP 7 (4+3). All tumors are most often diagnosed with stage D2, when there are already distant metastases. ADCP of Gleason score 7 (4+3) were diagnosed more often at this stage, among them there are more androgen independent tumors and they show a greater degree of focal neuroendocrine differentiation. All the results are in accordance with data from the literature suggesting that ADCP of Gleason score 7 (4+3) have a worse prognosis than ADCP of Gleason score 7 (3 +4)
Fibroadenoma of accessory breast tissue in axilla
Development of accessory breast tissue is a consequence the lack of regression remanths of milk line during embryogenesis. These remanths can be found anywhere on the ventral side of the body, extending from the axilla to the pubic region and most of them can be found in the axillary region. On such a tissue may appear almost identical changes that affect the normal breast, from benign non-tumor changes to malignant tumors. In our case report, the case is a 23 year-old woman who had a unilateral solitary lesions in the axilla, which was surgically removed. Starting diagnosis was ' Limphadnopathia axillaris lateris sinistri.' After removal and histopathological evaluation of the change, it was found that there is a tumor - fibroadenoma. There were also performed immunohistochemical ( IHH ) staining, with finding of a conventional fibroadenoma of the breast as expected. Accessory breast tissue in the axilla is a rare finding, and the tumors in this tissue even rarer. Histopathological confirmation is mandatory, with the need to exclude malignant tumors which are more common in these cases, and they occur at an earlier age
Significance of periacinar cleftings as supporting criteria in diagnosis of prostatic adenocarcinoma Gleason score-a 7 (3+4) and Gleason score-a 7 (4+3) and their relationship with parameters of predictive value
Diagnosis of different pathohystological diseases of prostate in the most cases is based on common benignant and malignant characteristics. The presence of periacinar cleftings (PC) is an additional criterion favouring prostatic adenocarcinoma. According to the presence and extent of PC, analysed on high power field (400x), glands were classified into 3 groups: group 1-glands without PC or with PC affecting ≤50% of gland circumference; group 2-glands with PC affecting >50% gland circumference in 50% gland circumference in ≥50% examined glands. The aim of our study was to determine the importance of presence of PC in prostatic adenocarcinoma (ADCP) of Gleason score 7(3+4) and 7(4+3) and establish the existence of differences in their appearance at ADCP with first and second dominant histological grade 3 and 4 in each different relationship based on correlation analysis of PC and parameters of the predictive value (preoperative value of serum prostate specific antigen, tumor volume, clinical stage and degree of focal neuroendocrine differentiation). The study included 33 ADCP of Gleason score 7, 26 (78.79%) ADCP 7(3+4) and 7 (21.21%) ADCP 7(4+3). In ADCP Gleason 7(3+4) periacinar cleftings are more common in tumors that are smaller, better differentiated (produce more PSA), which is diagnosed in less advanced clinical stages and showing a less degree of focal neuroendocrine differentiation. In ADCP Gleason 7(4+3) periacinar cleftings are more common in tumors which produce less value of serum PSA (poorly differentiated) and in tumors that are diagnosed in advanced clinical stages. Periacinar cleftings are common findings in prostatic adenocarcinoma Gleason score 7(4+3) which are considerd as tumors with worse prognosis. Because of all we can rank PC among the important additional criteria for the diagnosis of adenocarcinoma of the prostate
The descriptive and epidemiological characteristics of cervical cancer
Cervical cancer has long been a serious public health issue, both locally and worldwide. Efforts to control this disease should encompass prevention, as well as early detection and treatment, but also meticulous record-keeping and follow-up monitoring of affected women. In order to efficiently combat the disease, all of the above conditions must be met simultaneously. The goal of this article is to provide a layout of the fundamental descriptive and epidemiological characteristics of both cervical cancer patients and deaths resulting from the disease in Serbia, Europe and worldwide. We will pay special attention to a detailed epidemiological report on Central Serbia from 1999 to 2011. The article utilizes the approach of descriptive epidemiology to compound the knowledge about the disease, its incidence, and outcomes. The presented data was gathered from Globocan, a cancer surveillance database developed by the WHO, as well as the Cancer Registry of Central Serbia (for the aforementioned time period). There were 527624 new cases reported globally in 2012, corresponding to a standardized incidence ratio of 14,0 per 100000 women. Mortality-wise, there were 265653 deaths recorded in 2012, yielding a standardized mortality ratio of 6.8 per 100000 women. In other words, on average, every two minutes a woman dies of cervical cancer, totalling 720 cervical cancer mortalities per day. In Europe, there have been 58348 new cases in 2012 (11.44 per 100000 women), with 24378 deaths (3,75 per 100000 women). In Serbia, 1501 new cases were recorded in 2012 (23,8 per 100000 women), with 609 deaths (7,7 per 100000 women). These data make Serbia rank 62nd (out of 182 countries) in terms of incidence, and 84th in terms of mortality of cervical cancer, putting Serbia in the top half of the world on both criteria. According to the data supplied by the Cancer Registry of Central Serbia, the average standardized incidence ratio of 23.9/100000 women and the SMR of 7,2/100000 women in the evaluated time period point to an unfavorable epidemiological situation of this particular malignoma in Central Serbia. And while a deeper analysis of this interval reveals a slight drop in incidence of the disease in Central Serbia (y = 27,13-0,47x; p > 0,05, or roughly one new case fewer per 100000 women over the next two years), an increase in mortality is evident in the same period (y = 7.16+0,01x; p>0,05)