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This paper presents influence of the type of carbon nanotube functionalization on properties of poly(L-lactide) (PLLA) based nanocomposite materials. For this purpose surface modifications of multi-walled carbon nanotubes (MWCNTs) were performed by chemical and irradiation techniques, while thermo gravimetric analysis, UV-Visible and Fourier-transform infrared (FT-IR) spectroscopies confirmed successful covalent functionalization. Series of PLLA bionanocom-posites with different contents of functionalized MWCNTs (0.7; 1.6; 2.1 wt%), were synthesized via ring-opening solution polymerisation of L-lactide. FT-IR analysis confirmed that grafting of L-lactide, under controlled condition, is possible to perform starting from the surface of functionalized MWCNTs. From differential scanning calorimetry results it was concluded that even low contents of chemically and irradiation functionalized MWCNTs had a significant effect on thermal properties of the prepared nanocomposites, raising the values of melting and glass transition temperatures. Thermogravimetric analysis (TGA) has shown that the degradation onset temperature for composites with chemically functionalized MWCNTs, was much higher than that for the neat poly(L-lactide) sample and composites with irradiation functionalized MWCNTs. Morphology studies by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated that poly(L-lactide) covered surfaces and separated functionalized MWCNTs. Good dispersion of carbon nanotubes in polymer matrix enabled conductivity of synthesized materials, as determined by conductivity tests. [Projects of the Serbian Ministry of Education, Science and Technological Development, Grant no. III 45022 and Grant no. III 45020]

The paper presents the results of archaezoological analysis of fish remains from three locations at Viminacium (the Amphitheatre, Nad Klepečkom and Pirivoj), discussed jointly with finds of fishing equipment and relevant written sources on the subject. Albeit small and biased due to the hand-collection of animal bones, the fish faunal assemblage from Vimincium provides valuable data on the choice of exploited species, fishing and fish transportation practices, and patterns of consumption and deposition in the city and its surroundings. In addition to remains of locally available freshwater fish, occurring at all three sites, the Amphitheatre sample contained the remains of large anadromous sturgeons, possibly obtained from the downstream, Iron Gates area. Their size, contextual provenance, as well as their exceptional status according to written sources, indicates that there had been notable differences in access to high-quality fish among the different social classes at Viminacium. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III 47018: Viminacium, Roman city and military camp - research of the material and non material culture of inhabitants by using the modern technologies of remote detection, geophysics, GIS, digitalization and 3D visualization and Grant no. III 47001: Bioarchaeology of Ancient Europe - humans, animals and plants in the prehistory of Serbia]

Introduction: Acute coronary syndrome represents a group of several different clinical conditions, all caused by acute myocardial ischemia and/or necrosis. It includes: unstable angina pectoris, non ST elevation myocardial infarction (NSTEMI) and ST elevation myocardial infarction (STEMI). Being a part of the 'Vojvodina STEMI network' since 2014. Emergency Medical Service of Sombor provides early pre-hospital diagnostic, initial therapy and transport of STEMI patients (with constant monitoring of vital parameters) to the Institute of Cardiovascular Diseases of Vojvodina in Sremska Kamenica for primary percutaneous coronary intervention (pPCI). Object: The object of this paper is to analyze the possibility of providing prehospital thrombolytic therapy for STEMI patients transported to the ICVDV Sremska Kamenica, within current standard protocol. Methodology: For the purpose of this research, a retrospective analysis of the registry 'Time management protocol for STEMI patients' was made from January 1st, 2014 to December 31st, 2017. These time frames were examined: duration from the onset of pain to the established diagnosis, duration of transport to the Institute and overall duration time from the onset of pain to pPCI. Furthermore, patients were divided into four groups according to the time duration from the onset of pain to the established diagnosis: less than 1 hour, less than 2 hours, less than 3 hours and more than 3 hours. Results: 34, 18% of the analyzed patients were diagnosed as STEMI patients within one hour from the onset of pain, 36.71% within two hours, 10.13% within three hours and 18.99% needed more than three hours. For all of those that got their STEMI diagnosis within one, two and three hours, the average time was 71.47 minutes (1 hour and 11 minutes) and for those who got diagnosed after three hours that time was 318.13 minutes (5 hours and 18 minutes). Summarized average time from the onset of pain to the establishing of STEMI diagnosis was 194.80 minutes (3 hours and 14 minutes) for both groups. The average transportation time was 71.32 minutes (1 hour and 11 minutes), shortest being 47 minutes and the longest 88 minutes. For all those in the group that needed less than three hours for STEMI diagnosis, the average time from the onset of pain to the ICVDV was 158.08 minutes (2 hours and 38 minutes), and for those who needed more than 3 hours to get diagnosed the average time from the onset of pain to the ICVDV was 416.57minutes (6 hours and 56 minutes). The overall average time for all analyzed patients, from the onset of pain to the catheterization lab of the ICVDV was 295.13 minutes (4 hours and 55 minutes). Conclusion: Taking into account these results, it becomes reasonable to apply fibrinolytic therapy before transporting, keeping in mind at all times current standard protocols and safety precautions for possible fibrinolytic therapy contraindications. If transport of a STEMI patient to the PCI lab is not likely to happen within the first 120 min, because of some kind of technical disability or catheterization lab overload, and that patient is presented to the EMS within the first three hours from the beginning of pain, fibrinolytic therapy should be used in order to establish reperfusion and to buy some time until transport to the pPCI.

Food packaging industry presents one of the fastest growing industries nowadays. New trends in this industry, which include reducing food as well as packaging waste, improved preservation of food and prolonged shelf-life together with substitution of petrochemical sources with renewable ones are leading to development of this industrial area in diverse directions. This multidisciplinary challenge is set up both in front of food and material scientists. Nanotechnology is recently answering to these challenges, with different solutions-from improvements in materials properties to active packaging solutions, or both at the same time. Incorporation of nanoparticles into polymer matrix and preparation of hybrid materials is one of the methods of modification of polymer properties. Nano scaled materials with antimicrobial properties can act as active components when added into polymer, thereby leading to prolonged protective function of pristine food packaging material. This paper presents a review in the field of antimicrobial nanomaterials for food packaging in turn of technology, application and regulatory issues.

Properties of poly (lactic acid) (PLA) and its nanocomposites, with silica nanoparticles (SiO2), as filler were investigated. Neat PLA films and PLA films with different percentage of hydrophobic fumed silica nanoparticles (0.2, 0.5, 1, 2, 3 and 5 wt. %) were prepared by solution casting method. Several tools were used to characterize the influence of different silica content on crystalline behavior, and thermal, mechanical and barrier properties of PLA/SiO2 nanocomposites. Results from scanning electron microscope (SEM) showed that the nanocomposite preparation and selection of specific hydrophobic spherical nano filler provide a good dispersion of the silica nanoparticles in the PLA matrix. Addition of silica nanoparticles improved mechanical properties, the most significant improvement being observed for lowest silica content (0.2wt.%). Barrier properties were improved for all measured gases at all loadings of silica nanoparticles. The degree of crystallinity for PLA slightly increased by adding 0.2 and 0.5 wt. % of nano filler. [Projekat Ministarstva nauke Republike Srbije, br. III46001]

Segmented thermoplastic polyurethane copolymers (PURs) were synthesized using 4,4'-methylenediphenyl diisocyanate and 1,4-butanediol as the hard segment and α,ω-dihydroxy-poly(propylene oxide)-b-poly(dimethylsiloxane)-b-poly(propylene oxide) (PPO-PDMS) as the soft segment. The content of incorporated soft segments in PURs varied in the range from 40 to 90 wt.%. The structure, molecular weights and crystallinity of obtained copolymers were monitored by FTIR, 1H, 2D NMR spectroscopy, GPC and DSC analysis, respectively. Surface free energy analysis indicates the presence of hydrophobic (siloxane) groups on the surface, giving highly hydrophobic nature to the obtained PURs films. Water absorption measurements showed that the increase of the hydrophobic PPO-PDMS segment content, led to the decrease of percentage of absorbed water in copolymers. SEM and AFM analysis revealed that copolymers with lower content of PPO-PDMS segments have higher microphase separation between segments. The results obtained in this work indicate that synthesized PURs based on PPO-PDMS, demonstrated proper surface and morphological properties with a great potential for variety of applications such as hydrophobic coatings in biomedicine. [Projekat Ministarstva nauke Republike Srbije, br. 172062]

This study presents the influence of BA (6-benzyladenine) and BA+GA4+7 (6-benzyladenine + gibberellic acids 4 and 7) on feathering of one-year-old apple trees of two cultivars Jonagold and Čadel. Different concentrations of BA (300, 600, 1,200 and 1,800 mg L-1) and BA+GA4+7 (500, 1,000, 1,500 and 2,000 mg L-1) were applied, and two treatments for both chemicals were performed. The first treatment was applied at 70-cm height of nursery trees and the second 2 weeks later. Comparison was performed in relation to untreated control. An application of BA and BA+GA4+7 did not affect both rootstock and nursery tree diameter at 10 cm above the grafting union. Nursery trees of cultivar Jonagold were not influenced by treatments applied, whereas in cultivar Čadel, the treatment with BA+GA4+7 decreased apical growth of nursery trees. The development of sylleptic shoots in both cultivars tested was influenced by the type of growth regulator and concentration applied. Treatment with BA at 300 mg L-1 concentration in both cultivars tested did not influence total length and number of sylleptic shoots, as well as the number of sylleptic shoots longer than 20 cm. The most positive influence on all studied parameters was observed on nursery trees treated with the concentration of 1,200 mg L-1 BA. The lowest concentration of BA+GA4+7 (500 mg L-1) caused the low feathering of both studied cultivars. The higher concentrations (1,000, 1,500 and 2,000 mg L-1) similarly increased the number and total length of sylleptic shoots of nursery trees. [Projekat Ministarstva nauke Republike Srbije, br. TR31063 i br. III46008]

Quality parameters and the possibility of successful placement of buckwheat-enriched wheat bread on the national market are presented in this paper. Analysis of the market position of buckwheat-enriched wheat bread includes demands, offer and competition. Elements that affect the overall retail price of buckwheat-enriched wheat bread are given in details, along with SWOT analysis and marketing plan including target market, market supply and product marketing mix. According to all performed analyses it could be concluded that this product should be positioned on the national market, especially for people with special needs and requirements.

Psoriasis is a disease that has a profound impact on all aspects of life quality because over years patients are faced not only with poor health, but also with a number of restrictions imposed by the disease in their professional, social and emotional life. The aim of the study was to assess the level of impairment to the life quality in patients with chronic plaque psoriasis in relation to the clinical status of the disease, disease duration, and age and gender of the examinees. The cross-sectional study was conducted at the Clinic for Skin and Venereal Diseases of the Clinical Center of Niš. The total sample consisted of 142 examinees, 82 in the primary group (patients with psoriasis), and 60 in the control group (healthy volunteers). In order to assess the impact of psoriasis on life quality and compare it to the life quality of healthy population, the DLQI questionnaire (Dermatology Life Quality Index)was used and the disease severity was estimated based on the value of the PASI score (Psoriasis Area and Severity Index). The results showed that the groups of examinees differ appreciably in self-assessment in all five dimensions of life quality. In patients with psoriasis, there was statistically significantly lower life quality as a reflection of the disease severity and subjective perceptions of the disease impact and treatment impact, but also as a result of a number of restrictions in daily functioning caused by the disease. Patients with a severer clinical status gave low ratings to their ability to function in all areas covered by the DLQI questionnaire, especially in the symptoms and feelings subscale. The results of our study indicate the importance of a multidisciplinary approach in the treatment of patients with psoriasis and the possibility of introducing a supportive therapy, which would, along with a regular dermatological therapy, notably improve the life quality of these patients.

This paper presents an overview of the problem of detecting faults in low voltage electrical installations which are not normally detectable by the regulated electrical periodic verification inspections nor can be recognized by any classical protection components. Therefore, the conditions for the occurrence of fire are created at the source of these 'invisible' failures. This paper is concerned with the representation of modern methods and techniques for early detection of serial electrical arc. In the first part of the paper, a serial electrical arc is described, the conditions required for its formation as well as the physical processes that occur within it. An illustration of the modern protective components for detection of serial electrical arc is given in the second part of the paper.

The formation of polyurethanes based on vegetable oils is very complex and thus for industrial production of this materials it is important to determine the optimal temperature for polymerisation and finally to obtain materials with the proper mechanical properties. The goal of this work was to assess the kinetic of catalysed and noncatalysed reactions for polyurethanes based on castor oil as the polyol component and different types of diisocyanates. Due to the presences of hydroxyl groups on ricinoleic acid, castor oil is suitable for polyurethane preparation. The differential scanning calorimetry has been employed to study the polyurethane formation reaction using Ozawa isoconversion method. It was estimated that the catalyst addition decreases the activation energy. The highest reduction of activation energy was observed for the reactive systems with hexamethylene diisocyanate. Validity of obtained kinetic model was examined by FTIR spectroscopy following the apsorption of reactive groups. Obtained results of mechanical characteristics of the polyuretahane networks (with different NCO/OH ratio) confirmed that applied method could be used for prediction of optimal reaction condition in polyurethane networks synthesis.

The application of polymers for controlled drug delivery is influenced by no toxicity and solubility in different pH mediums. There already are existing pharmaceutical medicaments based on aqueous dispersion of an anionic copolymer methyl acrylate, methyl methacrylate and methacrylic acid. The aim of this work was to synthesise copolymers of methyl methacrylate and methacrylic acid and to estimate the effects of monomers ratio (1:1 and 1:2) on the molecular mass, polydispersity index, and solubility of obtained polymers. Acetone was used as a solvent because both monomers and the initiator azobisisobutyronitrile are soluble in it. FTIR method was used for functional group characterization, the gel permeation chromatography method for average molecular weights and the distribution of molecular weights determinations. High pressure liquid chromatography (HPLC) was applied for the estimation of residual monomers in obtained copolymers. The titration with ethanol solution of NaOH was used for assessing of monomer units in copolymers. The copolymer with the molar ratio of monomers 1:1 was soluble in water bufer with pH values higher then 6, while the copolymer with the molar ratio of monomers 1:2 was soluble in bufer with pH higher then 9.

In this work, we study the interactions of fast ions with graphene describing the excitations of the electron gas in graphene by a two-dimensional (2D) hydrodynamic model (one-fluid and two-fluid model). The two-fluid model reproduces qualitatively the split of plasmon dispersions into the low-frequency p-electron branch and the high-frequency s+p-electron branch. We calculate the stopping force and the image force on an ion moving parallel to a single sheet of graphene. Numerical results show that the presence of the low-energy, quasiacoustic plasmon in the two-fluid model gives rise to resonant features at low velocities around its 'acoustic' speed, which are not seen in the one-fluid model. The two models give virtually indistinguishable results for both forces at high speeds. Marked differences between the two models in the values of image forces at low speeds can be seen. Numerical results show that the magnitudes of both the stopping and image forces exhibit typical resonance-shaped velocity dependencies, with the peak positions moving to higher velocities for higher distances and with the overall magnitudes decreasing sharply with increasing distances. The second order corrections are found to be small, as expected for fast ions outside the electron gas, but their relative magnitudes should be easily discernible in experiments on ion grazing scattering from graphene. One notices effects which are similar to those obtained earlier for proton channeling in carbon nanotubes.

This paper looks at the difficulties of managing modem capital projects and endeavors to reduce the complexities to simpler and more understandable terms. It examines the project environment, defines project management and discusses points of difference from traditional management. In the second part of the paper are presented fundamentals for project success for different types of projects.

Unlabelled: In spite of the progress made in diagnostic procedures and development of the operating rooms technology, considerable neurological deficit after operation of tumors localised in the brain motor zone commits one to direct intraoperative identification of the motor zone. By introducing direct electrocortical stimulation into the routine intraoperative application the primary goal has been achieved -reaching the maximum degree of radicalness of surgical resection while preserving motor centres in the cerebral cortex., Method: We are hereby demonstrating a series of 60 patients operated for primary brain tumors localised in the area in the front and around the central sulcus. All operations have been performed under the general anesthetics. During the operations the method of direct electrostimulation (ES) was used for the purpose of identifying motor centres., Results: Intraoperatively a level of subtotal resection was achieved in 22 cases, while radical resection was possible in 38 cases. Significantly higher level of radicalness of surgical resection of the low grade glioma tumor was confirmed statistically in relation to the group of patients with glioblastoma multiforme by applying the ES cortex (p < 0.05). Patients with slow developing brain glioma have statistically considerably higher KI value in relation to the KI values in the group of patients with glioblastoma multiforme (p 0 < 0.01). Difference in the measured values of distance from the coronal suture based on the results of MRI measuring and finding obtained by ES, has shown a statistically considerably higher difference with a glioblastoma multiforme 8.26 +/- 4.288 mm when compared to slowly developing astrocitoma 5.88 +/- 3,080 (p < 0.05)., Conclusion: Electrostimulation of the brain cortex is a safe, simple and precise method for identification of the brain motor zone which enables prevention of additional postoperative deficit and higher level of surgical radicalness.

Introduction: The cardiovascular changes (vascular structure changes, hypertrophy of the left ventricle) contribute to both the increased cardiovascular morbidity and the mortality of essential hypertension. Therefore, modern treatment strategies should not only target blood pressure (BP) reduction but also normalize cardiovascular structure and function., Objective: Aim of the study was to determine the effect of the ACE inhibitor Fosinopril on the intima-media thickness of the common carotid artery and on the left ventricle mass after 9-month treatment of hypertensive patients., Method: The study included 40 patients with the arterial hypertension and the left ventricle hypertrophy verified by echocardiography. The patients were randomized on A) ACE-inhibitor--Fosinopril and B) without ACE inhibitor--atenolol, and they were followed up 9 months. The groups were not different by age, sex, and metabolic status. Color Duplex ultrasonography of the carotid arteries was performed by Acuson Sequia C236 with high-frequency linear probe of 8 MHz. The intima-media thickness of the common carotids on the left and the right was measured in diastole at 1.5 cm from the highest point of bifurcation under maximal magnification. Using the same device, the left ventricle mass and other parameters of the left ventricle were determined in M-mode and by means of 2D image., Results: After 9 months, BP in both groups was reduced in similar range (group A: systolic BP from 158 to 137 mmHg, and diastolic BP from 94 to 85 mmHg, and group B: systolic BP from 164 to 137 mmHg, and diastolic BP from 87 to 84 mmHg). The thickness of the intimomedial complex in patients using Fosinopril was decreased by 0.0278 +/- 0.03 mm, while in the group of patients that did not use the ACE-inhibitor, it was increased by 0.078 +/- 0.13 mm. The left ventricle mass in patients using Fosinopril was decreased by 5 grams (312 +/- 72 g vs. 307 +/- 77 g), while in group B patients, it was increased by 15 grams (323 +/- 79 g vs. 328 +/- 58 g. Diastolic function expressed through relation E/A was improved minimally in the group A, while it worsened by 0.1 in the group B. After 9 months, serious cardiovascular events were recorded (one infarction of myocardium and one hospitalization due to the unstable angina pectoris) in two patients of the group A, while four patients of the group B had serious CV events (1 cerebrovascular stroke and 3 hospitalizations due to unstable angina pectoris)., Conclusion: The results of our study showed that the application of Fosinopril in patients with the arterial hypertension and the left ventricle hypertrophy could efficiently block further progression of the intima-medial thickness of the common carotid artery, reduce the left ventricle mass, and improve diastolic function of the left ventricle.