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The elastomeric materials based on NR/BR/SBR ternary rubber blend were investigated. The polyisoprene (NR), butadiene (BR) and styrene butadiene (SBR) rubbers were used as network precursors and carbon black (CB) as an active filler (60 phr) for elastomeric materials preparation. For sample preparation, the mass ratio of NR to BR was constant, 1:1, but the SBR content was varied from 0 to 80 phr. The morphological, mechanical and thermal properties of prepared elastomeric materials were determined using scanning electron microscopy (SEM), mechanical tensile measurements and thermogravimetric analysis (TGA). Mechanical properties were assessed before and after thermooxidative aging during 168 h at 100 °C. The values of tensile strength, elongation at break, and hardness decrease up to 40 phr of SBR content and after that are increasing, but abrasion resistance of ternary rubber blends increases. Тhe thermal decomposition temperature obviously shifted to a higher temperature for the sample with 40 phr of SBR. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 45022 and Grant no. 45020]

Damping materials have been widely used in the vibration and noise control to reduce their harmful consequences in different areas such as their application in the drilling equipment, aerospace and naval vessels, transportation vehicles, bridges and high buildings. Because of severe environmental standards, the oil fabrication is developing synthetic environmentally friendly drilling fluids. For a vehicle, applications are produced: the outer and inner beltline seals and the glass run channel. The compression set is the important characteristic of elastomeric sealing materials as spontaneous stress release during application due to the internal pressure or external forces variations. The temperature and frequency-insensitive damping are of significance for industrial uses. Elastomeric hybrid materials based on terpolymers as network precursor are very common for sealants fabrication. The focus of this work was to prepare oil-extended elastomeric hybrid materials based on ethylenepropylene-diene monomer rubber (EPDM), ground calcium carbonate and furnace nano carbon black. Cure characteristics were carried out on oscillating disc rheometer. The crosslinking of rubber compounds was performed in a molding press. The compression set was assessed using the standard procedure. The morphology of the cryogenically fractured surface of samples with different content of paraffin oil was characterized by scanning electron microscopy (SEM). Mechanical properties and hardness were analyzed before and after the aging of obtained samples. Damping properties of prepared materials were determined using bending mode. The loss tangent, tan δ, was used as a measure of vibration energy dissipation.

Due to the growing problem caused by waste plastics, academia and industry, invest great dials of efforts to solve this problem and enable the sustainability of polymeric materials. One way, which can successfully solve this problem, is certainly the synthesis of new polymeric materials based on renewable raw materials. Therefore, in this paper, synthesis of polyester based on ricinoleic acid (as well as the methyl ester of ricinoleic acid) is presented, in order to obtain the polyol of the desired molar masses. The polymerization of the ricinoleic acid was performed in the presence of diethylene glycol, as an initiator, and titanium isopropoxide, as a catalyst. By analyzing the molar masses of the obtained polyesters, it has been confirmed that the control of the molecular weight of the polyricinoleic acid can be successfully accomplished by the addition of a precisely determined amount of diethylene glycol, thus enabling in this way the synthesis of polyols of desired properties. The molecular structure of the synthesized polyols is confirmed by FTIR and NMR spectroscopy. The analysis of the thermal properties showed that the glass transition temperatures of the synthesized polyols range from -70 to -80ºC, which makes it possible to apply these materials in low-temperature applications. The slight increasment of thermal stability is observed, only with the increasment of molecular weight, which was confirmed by TG analysis. The viscosity measurement results confirmed that as the molar weight of synthesized polyester increases, the viscosity of the samples also increases.

Modern man lyfestyle contributes to the increasing incidence of metabolic syndrome in the developed world. Prevalence of the metabolic syndrome in adults ranges from 20 to 25%, and it tends to increase. Each year, 3.2 million people around the world die from complications associated with this syndrome. Treatment involves cooperation of medical doctors of various specialties, but the decisive factor is patient motivation, given that the treatment requires significant lifestyle changes. Our hypothesis is that metabolic syndrome patients have reduced ability to plan, convert plan into action and effectively implement planned activities, showing signs of dysexecutive syndrome. The term executive functions comes from the English word 'executive', which also means the controlling, in neuropsychology reserved for high-level abilities that influence more basic abilities such as attention, perception, memory, thinking and speaking. The main objective of this study was to determine characteristics of executive functioning in patients with metabolic syndrome. The sample consisted of 61 subjects of both sexes, aged 20 to 60 years, divided into two groups - those with a diagnosis of metabolic syndrome and those without this diagnosis. The results suggest that people with metabolic syndrome showed significantly poorer performance in almost all indicators of executive functions, represented by Wisconsin Card Sorting Test (Wisconsin Card Sorting Test) variables.

In the process of macromolecule cross linking, the choice of type and quantity of the components and the experimental conditions are important to obtain the new cross linked materials with better mechanical and chemical characteristics. The cross linking method depends on the rubber type and structure. Intermolecular cross linking results in the formation elastomer network. The basis of the cross linking process, between ethylene propylene diene rubber (EPDM) and acrylonitrile butadiene rubber (NBR), is a chemical reaction. Fillers and other additives are present in different mass ratios in the material. The exploitation properties of the cross linked materials depend on the quantity of additive in the cross linked systems.

We examined the content of crops in 672 pheasants of both sexes. The pheasants have been shot at all seasons of the year in different hunting grounds in the Vojvodina Province. Out of total number of pheasants, 145 were shot in the spring, 128 in the summer, 229 in the fall and 179 in the winter. The examined pheasant crops contained mostly the seeds of weeds and grasses (62.2%), culminating in the fall (67.7%), and green feed (61.6%), culminating in winter and spring (79.8% and 70.4%, respectively), while the other kinds of feed were found in a considerably smaller number of pheasants. According to the average number of consumed particles, the seeds of weed and grass were in the first place (374 pheasants), culminating in the fall (431 pheasants) while the numbers of particles of other feeds were considerably lower, from 78% to 93%. According to quantity, corn was in the first place with the annual average of 8.4 g that culminated in the winter (11.3 g). The average proportion between the herbal and animal parts in feed was 99.6: 0.4 g in favor of the herbal feed, with seasonal variations from 99.2: 0.8 g in the summer to 99.9: 0.1 g in the winter. Analyzing herbal proportions in feed we saw that generative plant parts prevailed over the vegetative parts (92.0 g and 7.6 g, respectively). The percentage of animal parts present in the rations of pheasants was reduced over last 30 years from 33.5% to 0.4%.

Remnants of the fortified settlement Veletin are located on a hill of the same name (map marking 969) near the small town Janjevo, in the vicinity of the Monastery Gračanica in Kosovo, in a region rich in metal ore (pic. 1-3). Veletin is mentioned for the first time as a landmark in King Milutin’s charter for the Monastery Gračanica issued in 1321. Namely, the boundary of villages donated to the monastery ran "from Oštri vrh on Veletjen between Sušica and between Gušterica". Villages of Sušica and Gušterica still exist under the same names. The mentioned Veletin refers to the hill with a fortified settlement or fortress at the top. In the past the hill and the fortress were for a long time a characteristic part of the historical landscape. Thanks to its favourable geostrategic position, vicinity of important roads and above all to the nearness of rich silver mines, the hill of Veletin was settled and fortified in pre-historic time, then in antiquity and in the middle ages. It is supposed that the Roman town Ulpiana (Justiniana Secunda), near the Monastery Gračanica, developed because of the vicinity of silver mines and that as a municipium became a center of administration of Janjevo - Novo Brdo metals in the II c. Mining reached its peak in this area only in the first half of the XV c., during the reign of Serbian despots. When this part of Serbia fell under Turkish rule in 1455, mining began to decline. In 1488, during the reign of Sultan Bajazet II, special regulations were made for the organization of work in Janjevo silver mines, which testify about their importance. It is hard to form an opinion about the appearance of Veletin at the time the Gračanica Charter was issued. Mining was growing at that time and it is possible that there was a fortress with a small crew to protect Janjevo and other nearby mining settlements. Veletin is explicitly mentioned as a fortress only in three cartographic sources of a later date. The first was the Atlas by V. M. Coronelli, published in 1689 in Venice (pic. 4). In the part of the map in the center of which is Kosovo Field (Campo Cassovo), Veletin is marked near Janjevo (Iagneuo) as a ruin: "Valetino rouin." (ato), as evidence of its earlier importance. The second mention of Veletin is made in the Map of the central course of the Danube etc., by Johann Baptist Homan, prepared in Nuremberg between 1707 and 1724. Veletin appears for the third time in the New map of Dalmatia, Croatia etc., published by Mathias Seuter in Augsburg before 1758. From the time Veletin was destroyed it was never renovated as far as we know and time took its toll. The walls of the fortress and other buildings were used by local inhabitants as a source of building materials until they completely disappeared, what apparently happened in the 70’s of the XX c. Remains of the walls whose shape can be discerned under the soil show that the foundation of the fortress was adjusted to the configuration of the ground. That is to say, the hill of Veletin ends in sheer rock on northern and north-eastern sides and is completely inaccessible (pic. 5) while on other sides there are moderately steep terraced slopes (pic. 6-9) on which rampart walls were built following topographic relief (plans 10 and 11). Two plans of the fortress Veletin were published until now (pic. 10 11). The third plan, the most accurate, was not published. It shows that the for­tress had the form of an irregular polygon, and that it was defended by three perimeters of walls forming the Upper, the Middle, and the Lower town (pic. 12). In the south-eastern part of the Lower town are remnants of a rectangular and of a round building. Archeological probes on Veletin were performed by Edi Shukriu in 1987 and 1988. Archeological material shows that the oldest settlement was formed in Neolithic period, belonging to the Bubanj-Hum culture. The younger settlement is from the Iron Age and is connected to the Suva Reka group. Finds of fragments of Attica ceramics of black-figure style points to connections with Greece in the VI c. (pic. 13/1,2), while curved fibula with charniere shows that the inhabitants of Veletin in V-IV c. possessed jewelry of high quality and aesthetically embellished (pic. 13/3,4). There are yet no material remains from the Hellenistic period. Rampart walls were built in the late classical period and numerous finds of tiles and ceramics could be dated to the same period (pic. 13/5-7). Also were found fragments of medieval ceramic vessels (pic. 13/8), two iron arrows (pic. 13/9,10), and an earring of bjelobrdo type dating from X-XII c. (pic. 13/11 and pic. 14). Destruction of remains of Veletin is continuing to this day. In more recent times part of the eastern rampart (?) wall (pic. 15) was damaged, while in the vicinity part of a threshold of the town gate or of some other larger building was discovered (pic. 16).