Human papillomavirus (HPV) infection is one of the most common viral infections in sexually active population worldwide, and is the main cause of cervical cancer, which is the fourth most common cancer among women. Serbia ranks third in incidence and mortality rate of cervical cancer in Europe. We conducted a cross-sectional study considering parents’ motivation for the HPV vaccination of their children. Statistical analysis included descriptive statistics and a logistic regression model. We found that the strongest motive was “Recommendation from paediatrician” (20.2%), followed by the attitude that HPV vaccine protects against cancers in different localization (15.4%), the motive “It is better to vaccinate a child than expose them to potential risk of HPV infection” (13.3%) and “Feeling anxiety due to a possible infection and cancer in the child” (13.1%). For those parents that vaccinated their child for some other strongest motive, reasons like “Vaccine is free of charge”, “Recommendation from friends and family” and motive „My child received all obligatory vaccines, so I want to receive this one as well“, were significantly more frequently selected. In the group where paediatricians’ recommendation was not a motive for accepting the HPV vaccine, the largest percentage of parents (89.6%) selected motive “HPV vaccine protects against cancers in different localization” and the motive “It is better to vaccinate a child than expose them to potential risk of HPV infection” (78.1%). Paediatrician’s recommendation is very important for parents’ decision to vaccinate, however, other motives also influenced and had significance in making the parents’ decision to vaccinate their children against HPV. Encouraging trust in public health authorities in Serbia, highlighting the advantages of the HPV vaccine and further encouraging healthcare workers to give stronger recommendations can increase the HPV vaccine uptake. Finally, we provided the basis to create more targeted messages that will empower parents to vaccinate their children.

Mullite and mullite–alumina ceramics materials with dominance of the mullite phase are used in different areas of technology and materials science. Porous mullite ceramics materials can be used simultaneously as refractory heat insulators and also as materials for constructional elements. The purpose of this work was to investigate the WO3 nanoparticle influence on the evolution of the aluminum tungstate and zircon crystalline phases in mullite ceramics due to stabilization effects caused by different microsize ZrO2 and WO3. The use of nano-WO3 prevented the dissociation of zircon in the ceramic samples with magnesia-stabilized zirconia (MSZ), increased porosity by approximately 60 ± 1%, increased the intensity of the aluminum tungstate phase, decreased bulk density by approximately 1.32 ± 0.01 g/cm3, and increased thermal shock resistance by ensuring a loss of less than 5% of the elastic modulus after 10 cycles of thermal shock.

Effect of methyl methacrylate (MMA) as a binder and heating treatment were investigated to improve green alumina compacts machinability. Properties of green compacts and their corresponding sintered samples prepared with and without MMA were compared. Investigation of green and sintered properties was performed on samples compacted at applied pressures up to 150 MPa. After pressing, samples with MMA were thermally treated at 115oC. The intention was to enhance the polymerization of MMA at a temperature a little higher than the glass transition temperature (Tg = 103oC) of poly (methyl methacrylate). Green compacts with MMA had higher green density values than those without MMA. Sintered samples with MMA had lower values of sintered density and higher values of total porosity; after sintering, relative linear shrinkage was around 15 % for the whole range of applied pressures. The possibility of easily machining the green compacts with MMA produces great possibilities for application in many fields

Introduction. Hepatitis A virus is the most common cause of acute viral hepatitis, and in people over 25 years of age the disease may have different degrees of severity. Even though hepatitis A virus infection was long believed to be transmitted strictly by fecal-oral route, now this virus is classified among sexually transmitted diseases. Homosexual population, especially those positive for human immunodeficiency virus, is at the greatest risk of hepatitis A virus infection. Case 1. A twenty-six-year-old male homosexual was admitted with clinical and laboratory findings of acute hepatitis. The patient tested positive for enzyme-linked immunosorbent assay immunoglobulin M antibodies to hepatitis A virus and human immunodeficiency virus antibodies, and later on human immunodeficiency virus infection was confirmed by polymerase chain reaction test. After the discharge, the antiretroviral therapy was initiated. Case 2. A twenty-seven-year-old male homosexual was transferred to our clinic from the Regional Hospital, where he was hospitalized due to acute hepatitis A virus infection, after a positive serological test for anti-human immunodeficiency virus antibodies. Human immunodeficiency virus infection was confirmed by polymerase chain reaction test, and upon discharge, antiretroviral therapy was initiated. Conclusion. In order to take the most effective preventive measures, it is very important to identify individuals and groups at high risk of coinfection with human immunodeficiency virus and hepatitis A virus. Timely vaccination against hepatitis A virus among people living with human immunodeficiency virus is recommended and therefore it is necessary to design effective strategies for education of groups at risk.

Abstract Polycyclic aromatic hydrocarbons (PAHs) are formed from anthropogenic activities, i.e. industrial emissions, incomplete combustion of petroleum, coal and other fossil fuels and other industrial and domestic activities. Research areas of this study are four representative locations in the industrial complex, in the city of Banja Luka, Republic of Srpska, Bosnia and Herzegovina. The main objective of the paper is to determine the ecological risk and to assess probable sources of PAHs contamination in soil and groundwater. The results of this study reflect the effects of coal combustion (pyrogenic origin), petrogenic and biomass origin and may provide basic data for the remediation of PAHs in the location. The ecological risk in soil (at depths of 30, 100, 200, 300 and 400 cm) and groundwater is determined. The mean values of ecological risk in soil and groundwater decreased with soil depth. Values of RQ(NCs) for groundwater were found at high ecological risk, for Ant, Chr, DahA, Acy, Pyr, BaA, Phe, Flo, Nap, Ace and Fluo, with values 28.57, 20.59, 300.00, 242.86, 185.71, 1700.0, 76.67, 53.33, 15.83, 100.00 and 57.14, respectively. ∑16PAH indicated high ecological risk for most PAHs, which decreased with soil depth. The value of RQ(NCs) for ΣPAHs in groundwater indicates high ecological risk (ΣPAHs ≥ 800 and RQ(MPCs) ≥ 1). This is the first study on the ecological risk of PAHs in soil and groundwater in industrial soils in Banja Luka and provides baseline information for further studies and additional investigations of this industrial complex.

Macroporous silica ceramic was obtained using clay and diatomite. Boric acid as a low-cost additive in the amount of 1 wt% was used. These porous materials were obtained at low forming pressure (40-80 MPa) and lower sintering temperature (850-1300 ?C) for 4h in air. The influence of boric acid, forming pressure, and sintering temperature on the microstructure, porosity parameters, and mechanical properties of obtained porous monoliths were investigated. As-received and the modified samples were characterized by X-ray diffraction, FTIR, SEM, and mercury porosimetry measurements. As for modified clay and diatomite, they were pressed at 60 MPa and then sintered at 1150 ?C, obtaining porosities of about 10 % and 60 %, respectively. Both of the analyzed samples had the pore diameter in the range of macroporous materials. The pore diameters of clay samples are ranging from 0.1-10 ?m, whereas the pore diameter of diatomite samples was slightly lower with values ranging from 0.05-5 ?m. Modified diatomite samples have a lower Young modulus in comparison to modified clay samples.

Concentrations of dangerous and harmful substances (PCB, TPH and heavy metals) were determined in soils in an industrial zone near the center of Banja Luka and the Vrbas River. PCB, TPH and heavy metals were found in the analysis location as a result of general anthropogenic factors. Contaminated soils have a negative impact on human health and the environment. The mean concentrations of Pb, TPH, Cu, PCB, Ni, Cd and Hg were 4874, 4105, 545.7, 282.1, 225.7, 12.15 and 5.896 mg/kg, respectively. Results show that concentrations were very high for all analyzed parameters, and these values indicated that the soil was highly polluted. Principal component analysis has shown that industrial factors and human activities are the cause of pollution. At the location it is necessary to determine the origin of pollution and recultivation and remediation activity of planned activity.

Drawing upon Fischbein's theory of figural concepts, the starting point of the paper is the use and value of the history of geometry in mathematics education - first point that we make historical reference are theorems of Eudemus of Rhodes and Thales of Miletus and the second one is elaboration of these theorems in work of Serbian mathematicians Mihailo Petrovic Alas. Fischbein's theory is mainly based on a hypothesis that geometry deals with mental entities, the so-called geometric figures, which simultaneously possess conceptual and figural properties. Fischbein called the geometric figures figural concepts because of their nature. We have analyzed the internal tensions of the concepts of angle and cube, which may appear in figural concepts because of their double nature, developmental aspects and didactical implications. The goal of the research was to examine the pre-service primary school teachers' geometric reasoning regarding the correlation between figural (pictoral) and conceptual properties of geometric objects (angle and cube) in order to obtain a framework for creating didactic situations that reduce the gap between figure and concept. The results of this study show that the figural (pictoral) structure of an angle (and cube) dominates in the geometric reasoning of the pre-service primary school teachers over its formal conceptual constraints. There were some differences in situations when an image is helpful in solving tasks involving the concepts of the net of the cube and the cube itself.

Clean, fresh air is the most important requirement for good indoor air quality (IAQ) in all buildings, but it is especially important with regard to the environments within hospitals and other healthcare facilities. The literature indicates that buildings with heating, ventilating and air conditioning (HVAC) systems may have an increased risk of sick building syndrome (SBS) and building-related illness (BRI) if they are not well maintained. Microorganisms are brought into hospitals by people, air currents, water, construction materials and equipment. The main objective of this study was to assess the degree of fungal and bacterial contamination in the University Clinical Centre in Banja Luka, which is directly connected to the HVAC system. Airborne bacteria and fungi in the indoor hospital environment were assessed experimentally. Air samples were collected during the winter season. This paper presents the results related to the concentration of microorganisms expressed in colony forming units per cubic metre of air sampled (in CFU/m) together with the microclimatic parameters temperature and relative humidity. The results of monitoring indicate the effectiveness of HVAC systems in reducing microbiological contamination.

This paper investigates the impact of accidental release of chlorine gas in surrounding areas consequences of chlorine gas leak studying the negative effects on both the environment and individuals. Chlorine and its consequences have a far more reaching effect in society that one may have imagined. The ALOHA software has been used in this paper to modelling of chlorine release. The modelling was performed for an accidental release of 3.373 tons chlorine gas from unsheltered single storied for one hour. For a typical average atmospheric condition in location, this accidental chlorine release would cause a red zone of 3.0 kilometres (AEGL-3=20 ppm), orange zone of 7.1 kilometres (AEGL-2=2 ppm) and yellow zone stretching to greater than 10.0 kilometres (AEGL-1=0.5 ppm) to downwind from the source.