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The possibility to utilize the antibacterial and antibiofilm potential of essential oils (EOs) in dentistry is recognized and best seen in the design of EO-based mouthwashes. The up-to-date results, obtained with the most commonly used formulation being consisted of thymol, eucalyptol, menthol, and methyl salicylate (Listerine), proved its efficacy against plaque and gingival inflammation. However, novel alcohol-free products remain to be further investigated. Commercially available mouthwash containing curcumin, clove oil, mentha oil, eucalyptol, thymol and tea tree oil, and the mouthwash based on ginger EO (a-zingiberene, b-bisabolene, b-sesquiphellandrene, curcumene), reduced plaque index and improved periodontal status of the patients. The plaque index was also reduced and overall healing was improved after the surgical removal of the third molar by mouthwash containing John wort oil. In addition, Cinnamomum zeylanicum EO-based mouthwash and mouthwash containing peppermint oil were efficient against stomatitis and xerostomia, respectively. In addition to beneficial effects achieved in the mouth, i.e. at the appropriate site of application, novel investigations pointed-out that EO-based mouthwashes could be recognized as efficient in the reduction of bacterial and viral aerosols. This has been shown for Listerine, and for several mouthwashes containing following active substances of plants' EO origin: a-farnesene, b-farnesene, farnesol, nerolidol, a-bulnesene, eremanthin, b-sesquiphellandrene, spiroether, cinnamylacetate, cinnamaldehyde, eugenol, menthol, and carvacrol. This finding could be of special interest, in order to be included in further clinical studies related to COVID -19 pandemic.

The aim of this study was to evaluate the effects of winter cover crops (CCs) on soybean agronomic performance and their implications for different physiological groups of rhizosphere microorganisms in two sustainable production systems. The production techniques for rye, peas, and oats are well known, but their suitability as CCs for soybean (organic and low-input) production needs to be examined. After two years of trials, soybean yields among the two tested winter CCs (peas and oats (P + O) and rye (R)) were statistically significant only for P + O. The soybean yield in succession to P + O as winter CCs was 3.0 t ha−1, whereas in succession to R, it was 2.7 t ha−1, and in the control plot, it was 2.6 t ha−1. The average soybean grain protein content was in the range of 40 to 41% dry matter (DM), while the oil content ranged from 20 to 22% DM. Protein and oil content primarily depends on the selected soybean variety and it is confirmed through this study that, in the studied system, we can obtain adequate grain nutritional quality. The results indicate an increase in the abundance of total bacteria, ammonifiers, and free N2-fixing bacteria in the rhizosphere, depending on the selected CCs, and differences between the tested production systems. According to this study, winter cover crops (CCs), including peas and oats (P + O) and rye (R), can be included in crop rotation for soybean. CCs can be the answer to agro-biodiversity empowerment in less diverse soybean cropping systems, along with other benefits that CCs can provide at the level of crop rotation. In addition, in almost all aspects of the study, organic production was ahead of low input. Low input is an adequate production system if there are no opportunities for organic certification and for producers who are aware of the advantages of sustainable systems, and it can also represent a transitional path towards regenerative agriculture or organic production. [ABSTRACT FROM AUTHOR]

Bacillus spp. are well known to protect plants from seed or soil-borne pathogens by the synthesis of various metabolites with antimicrobial activity, such as hy­drolytic enzymes and antibiotics. This study aimed to select the most effective Bacillus spp. from a group of ten antagonistic strains by antifungal activity assay. Bacillus strains were primarily isolated from the soil and identified as B. safensis, B. pumilus and B. subtilis by 16S rDNA sequencing. The four analyzed fungi: Macrophomina phaseolina, Alternaria alternata, Cladosporium cladosporoides, and Sclerotinia sclerotiorum, were obtained from sunflower seeds and identified using PCR analysis and primers specific for ITS region. The antifungal activity of bacterial strains was examined in a dual plate assay. Bacillus spp. demonstrated the highest antagonism against S. sclerotiorum, followed by C. cladosporoides, M. phaseolina, and A. alternata, with an average percentage of growth inhibition (PGI) of 77%, 70%, 64% and 59%, respectively. Overall, Bacillus spp. included in this study demonstrated a rather strong biocontrol potential, although the effect of particular strain varied depending on the tested fungi. The highest antagonistic effect toward M. phaseolina and A. alternata was exhibited by B. safensis B2 and B. pumilus B3. B. pumilus B11 and B. subtilis B32 were the most efficient against C. cladosporoides, whereas B. pumilus B3 and B. subtilis B7 had the highest antifungal activity against S. sclerotiorum. Findings point to the fact that the most effective Bacillus spp. could be used as potential biocontrol agents for improving plant health and productivity.

A novel composite tandem sandwich structure made of aramid fabric and aramid honeycomb, impregnated in a matrix of epoxy resin combined with poly (vinyl butyral), PVB, is proposed. The composite was additionally reinforced with a small concentration of titanium diboride nanoparticles, TiB2, to study its effect on impact resistance. Sandwich composite samples were fabricated by impregnating the aramid fabrics and honeycomb in subsequent layers with the system epoxy/PVB/TiB2. Their mechanical behavior was examined through three-point bending test, Charpy impact test, and compressive test. The chemical reaction between PVB and epoxy resin, and chemical inertness between the nanoparticles and the other constituents were confirmed by FTIR analysis. The flexural strength and stiffness increased by 27.6% and 62.5%, respectively, in the presence of TiB2 reinforcement. Impact tests showed increase of 104% in impact toughness in the case of samples with TiB2. Nano TiB2 did not increase compressive strength of the proposed sandwich structure, but it improved its stiffness and reduced the permanent deformation. The achieved improvements in mechanical resistance make this new composite structure a promising candidate for automotive, airspace, naval, civil engineering, sports equipment industry, and for use in defense technologies. [ABSTRACT FROM AUTHOR]

Aluminum alloys of 7xxx series have the highest strength among all aluminium alloys, but they are prone to the corrosion-induced damage. The retrogression and re-aging heat treatment (RRA) is a heat treatment process applied on the 7xxx series aluminum alloy in T6 temper condition to provide a significant improvement of the corrosion resistance with or without small loss in its strength. The paper presents the influence of RRA treatment on the electrical conductivity and mechanical properties of the aluminum EN AW 7049A-T6 alloy. The retrogression heat treatment was performed at various temperatures (from 180 C to 280 C) and times (from 3 min to 45 min), while re-aging was performed at 120 °C for 24 hours. It has been found that with increasing both temperature and time of retrogression, hardness and strength decrease but the toughness of the alloy increases in comparison to the initial T6 temper. Contrary to hardness values, electrical conductivity rises with an increase in holding time and temperature of retrogression.

Many epidemiological studies have shown a positive association between black carbon (BC) concentrations and exacerbation of allergic rhinitis and asthma. The aim of this study was to examine, for the first time in Serbia, the connection between visits to emergency services due to worsening of allergic rhinitis and allergic asthma and the concentration of BC in the air. Materials and methods: A time-stratified case crossover design was applied for emergency room visits due to allergic rhinitis and worsening asthma that occurred in the Užice region between 2012-2014. Data on visits were routinely collected at the Uzice Health Center. Results: A statistically significant association was observed between the worsening of allergic rhinitis and BC concentration two days before the visit to the emergency department (UO = 359, UO = 3.20 and UO = 3.24, depending on whether the analysis is not adjusted or adjusted for appropriate weather conditions). There was also a statistically significant association between worsening of allergic asthma and BC concentration two days before the emergency service visit (UO = 3.15, GP = 0.98-10.14) and three days before the emergency service visit (UO = 2.98; UO = 3.23 ; UO = 2.98). Conclusion: Exposure to soot, especially during the heating season, increases the risk of emergency services due to worsening of allergic rhinitis and asthma.

Background/Aim: Understanding the composition of bacteria in infected root canals is important for ameliorating the treatment strategies that lead to the elimination of pathogens and infection control, but also prevent reinfection. Aim of this study was to investigate microbial composition of primary infected root canals with apical periodontitis of young permanent teeth, originating form school children in Serbia, and its association with clinical symptoms.

The aim of the study was to examine the effects of management practice on microbial properties of soil under soybean production. The study included 180 samples of soil under certified organic soybean production and 80 samples in conventional production system. An abundance of the examined microbial groups was assessed using the indirect dilution method, followed by plating of soil suspension on different selective media, while dehydrogenase and β-glucosidase activity was measured spectrophotometrically. Our data indicated that the management practice affected the structure and activity of microbial com­munities. A significant positive effect of organic farming on Azotobacter spp., free N-fixers and abundance of actinomycetes was identified. The influence of management system for the total number of bacteria, ammonifiers and fungi was not observed. Significantly higher dehydrogenase and β-glucosidase activity was recorded in the soils under organic farming compared to the conventional farming. The obtained results showed an increase in organic matter content, associated with organic soil management, and its positive correlation with soil microbial properties. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR 30122]

The relationship between soil carbon fractions in Chernozem soils was assessed in soil samples of three different environments: arable soil, grassland and oak for­est. Grassland and oak forest had higher soil organic carbon (SOC), carbon soluble in hot water (HWC), particulate organic carbon (POC) and mineral-associated carbon (MOC) than the arable soil. The POC/MOC ratio was lowest in arable soil, indicating a smaller carbon pool for microbial turnover. POC increases with higher total SOC, indicating that the pres­ervation of organic matter depends on the renewal of labile fractions. Our results showed that fertilization had active role in soil carbon stabilization, while crop rotation had less effect on a soil carbon turnover. Our result could contribute to the better understanding of SOC fractions composition and relevance in Chernozem soil, thus could help in selection of cropping management systems for SOC preservation. [Projects of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR031072 and Grant no. TR031073]

The objective of this study was to investigate the possibility of using microbial strains as residue decomposers and to determine the effect of these strains on chemical and microbial properties in the residue-amended soil. Greenhouse experiment consisted of eight Bacillus treatments, three Trichoderma treatments, and their combination, all applied to non-sterile chernozem soil amended with wheat straw. Incorporation of wheat straw improved soil chemical and microbial properties, while the extent of residue decom­position under microbial strains was intensified. Microbial treatments significantly affected the soil pH, the content of carbonate, total carbon, soil organic carbon, humus, and available phosphorus and potassium. Bacterial and fungal treatments also significantly influenced the total microbial number, ammonifiers, N2-fixers, fungi, actinomycetes, oligotrophs, copiotrophs, and cellulolytic microorganisms. The effect of microbial treatments varied depending on the applied strains and examined properties, with Bacillus strains being more promising residue decomposers compared to Trichoderma strains. The most effective microbial strains could be used as potential decomposers of crop residues. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR31072]

The objective of this study was to assess the effect of biochar soil amendment (BSA) on chemical and microbial properties in different agricultural soils in Vojvodina Prov­ince. Short-term pot experiment consisted of five biochar application doses (0, 0.5, 1, 2, and 3%) and five contrasting soil types (Mollic Gleysol, Eutric Cambisol, Calcaric Fluvisol, Gleyic Chernozem, and Haplic Chernozem), planted with sunflower (Helianthus annuus L.) and winter wheat (Triticum aestivum L.). The examined chemical and microbial properties were significantly influenced by soil type and interaction of experimental factors. Significant influence of biochar on the contents of calcium carbonate (CaCO3), total nitrogen (N), total carbon (C), soil organic carbon (SOC), humus and potassium (K) of the tested soils was observed. Biochar also significantly affected the number of azotobacters (AZB), fungi (FNG), actino­mycetes (ACT) and copiotrophic bacteria (CB). The effect of BSA varied depending on the applied dose, with higher values of the examined chemical and microbial parameters at higher doses of application. Further studies on using biochar in soils with low fertility will be neces­sary to establish its efficiency as an enhancer for agricultural production in Serbia. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR31072]

The effect of sensitization on the intergranular corrosion (IGC) of TIG welded AlMg6Mn was investigated by means of scanning electron microscopy (SEM) and corrosion NAMLT tests. The as-received hot rolled AlMg6Mn alloy plates with a thickness of 8 mm were welded by TIG welding with S-AlMg5 as a filler material. Specimens were sensitized at 100°C for 7 days. It was found that welded specimens are sensitive to IGC. The. mass loss in NAML test was 106.7 mg/cm². The welding increases the susceptibility to IGC, since the mass loss of the base metal at the same test was 70.7 mg/cm². The increase of susceptibility to IGC is attributed to significant continually precipitated Mg-rich phase along the grain boundaries during the sensitization treatment.

Introduction/Objective. Patients with submassive (intermediate risk) pulmonary embolism (PE) represent a very heterogeneous group, whose therapeutic strategy still questions whether some groups of patients would have net clinical benefit from fibrinolytic therapy (FT). Methods. From the institutional pulmonary embolism registry, 116 patients with submassive PE were identified, and the relation of their outcome to FT was analyzed using the propensity score (PS) adjustment. The primary endpoint was the composite of death, in-hospital cardiopulmonary deterioration, or recurrence of PE. Safety outcomes were updated TIMI non-CABG related major and minor bleeding. Results. According to Cox regression analysis, the incidence of composite endpoint was significantly lower in patients treated with FT compared to anticoagulant therapy (AT) only (PS adjusted HR 0.22; 95% CI 0.05–0.89; p = 0.039). But, when patients were stratified into four PS quartiles, only patients in the highest PS quartile that received fibrinolysis, had significantly lower composite event rate than patients treated with AT (HR 0.20; 95% CI 0.01–0.56; p = 0.016). The overall mortality of the study group was 5.2% and there was no significant difference between the treatment groups. Total bleeding was significantly more frequent in FT patients (HR 3.07; 95% CI 1.02–13.29; p = 0.047), but not the major one. Conclusion. The use of FT was associated with a better outcome compared to AT in patients with submassive PE, but the benefit was mainly driven from those with highest values of PS, i.e. with the highest baseline risk. The rate of major bleeding was not significantly increased by FT.

Soybean yield depends on the choice of cultivar, soil fertility, cultivation practices, and weather conditions in different years. Ploughing down crop residues increases the content of soil organic matter, and thereby positively affects soil fertility. The use of crop residues as an energy source has been promoted in recent years. It would be wrong to refer to this as a renewable energy source as the removal of crop residues from agricultural fields reduces and ultimately damages soil fertility, which in turn leads to reduced yield and a crop residue decrease in the future. Due to the reduced application of manure and organic fertilisers, it is necessary to return crop residues to the soil to preserve soil structure and prevent soil fertility decline. The effect of ploughing down crop residues of preceding crops on soybean yield has been the focus of studies for eleven years. Ploughing down maize crop residues resulted in the soybean yield increase by about 11.69%, i.e. the annual yield increase ranged from 2.89% to 15.94%.

The study monitored microbial abundance and dehydrogenase activity in chernozem soil under different cropping systems. Soil samples were taken from the long-term trials Crop Rotations and IOSDV, at the Rimski Šančevi experimental field of the Institute of Field and Vegetable Crops. The soil samples were collected in two years from ten cropping systems at three sampling depths. Number of the examined microbial groups was assessed by the indirect dilution method, while dehydrogenase enzyme activity was measured spectrophotometrically. Number of the tested microbial groups and dehydrogenase activity varied significantly depending on the cropping system and year of study, while sampling depth significantly affected enzyme activity. The highest number of microorganisms was obtained in non-agricultural soil and unfertilized soil under 2-year and 3-year rotation, while the highest dehydrogenase activity was recorded in non-agricultural soil and soil under wheat grown in monoculture.

Background/Aim. Self-rated health (SRH) is a widely adopted tool to compare health across countries. Relationships of socio-demographics with SRH in later life have been extensively cross-nationally observed. However, cross-comparisons of the effects of health behaviors (i.e., eating habits, smoking, and alcohol consumption) and health status (i.e., chronic diseases) on SRH are less frequent. Our aim was to examine SRH differences between older adults in Italy and Serbia and to observe the role of predictors of SRH particularly referring to health behaviors in both countries. Methods. Two samples of 4,406 Italians and 3,539 Serbs aged 65 and older were extracted from national health surveys conducted in 2013. For this secondary analysis, SRH, sociodemographics, health status variables, and health behavior factors were selected. In the multivariate logistic regression models, SRH was the dependent variable while the selected independent predictors were socio-demographics, characteristics related to health status and to health behavior. Results. Both Italians (30.3%) and Serbs (22.3%) reported lower values of good- or very good-SRH than the European average (36.9%). The logistic regressions showed that Serbs reported poor–SRH significantly more often than Italians. Moreover, gender, education level, chronic diseases, and daily life limitations resulted as significant predictors of SRH in both national samples. In addition, vegetables intake was positively associate to SRH among Italians, while among Serbs an adequate fruits intake was positively associated to SRH. Conclusion. Health behavior and health status factors are associated with better SRH in the population aged 65 and older. The effects differ between countries. It is essential that decision-makers of the implementation of international preventive strategies take into account the specific characteristics of countries in the organization of interventions for the aged population.

Urban gardening is an activity that has been rapidly increasing. The aim of this study was to point out the common mistakes in cultivation practices made by producers on small city areas. Total of 96 individual plots under vegetable crops were sampled (56 from garden plots of the city of Novi Sad, and 40 from field plots in the suburbs). There was no significant difference in the content of organic matter between these two groups of tested soils. The contents of readily available P2O5 and K2O were significantly higher in garden soil than in the field plots for production of vegetables. According to the content of pseudototal copper, 39% of samples belonged to the category of critical concentration and/or above MAC in the urban soil. Obtained results prove the pollution of small area gardens due to high anthropogenic effect of excessive use of mineral fertilizers and copper-based fungicides.

Aim of the study was to examine the effects of soil use on soil microbial properties at five locations in Central Serbia. The study included 42 samples of soil under certified organic system, 8 samples under conventional system, and 30 samples of abandoned soils. The number of examined microbial groups was assessed using the indirect dilution method followed by plating of soil suspension on different selective media, while dehydrogenase activity was measured spectrophotometrically. The number and activity of microorganisms at the tested plots primarily depended on the soil pH. The acidic soil reaction caused more rapid fungal growth and lower presence of actinomycetes and Azotobacter sp. There were no significant alterations in the number of microorganisms, ammonifiers and fungi under the specific soil use system. Significantly higher dehydrogenase activity was recorded in the abandoned soils and soils under organic systems compared to the conventional farming.