Genotypic variability of morphological characteristics of English oak (Quercus robur L) acorn

This paper deals with the acorn morphology (length, diameter and mass) analyzed in seventeen English oak genotypes (Quercus robur L)from the English Oak Clonal Seed Orchard Banov Brod (Srem,Vojvodina). The highest values of acorn mass and length were measured in genotype 5. The largest diameters were measured in genotypes 6 and 21. Genotype 35 had the lowest acorn mass, length and diameter. The results from this study should serve as guidelines for the selection of trees yielding fruits possessing the desirable morphological characteristics

Genetic variability of mineral elements concentration in pepper varieties (Capsicum annuum L.)

Pepper (Capsicum annuum L.) is one of the major members of the vegetable kingdom. The differences between the individual varieties in mineral nutrition and the uptake of mineral elements have provoked our interest for the investigations of their genotype specificity. The chemical composition of pepper leaves at flowering and at the end of the growing season was analyzed. On the average, the content of total ash was app. 22%, namely 19-20% (soluble) and 2-3% (insoluble) at both stages. The highest accumulation values were obtained with nitrogen, then potassium, calcium and phosphorus, whereas the lowest with sodium. The most remarkable genotypic differences were recorded at the end of the growing season. The results obtained clearly demonstrate the chemical heterogeneity of pepper varieties. This crop may be grown successfully only if specificity of its mineral nutrition is known

First Isolation of Exiguobacterium aurantiacum in Serbia

Exiguobacterium aurantiacum is isolated from a variety of environmental samples but rarely from patients. The aim of the study was to represent isolation of unusual bacterial strains that could cause infection in patients. Final identification was performed using matrix-assisted description/ionization time-of-flight mass spectrometry (MALDI-TOF). Two isolates strains of E. aurantiacum were isolated, one isolate from distilled water used during surgical treatment and the second one from a patient with bacteremia after radical prostatectomy, both sensitive to all tested antimicrobials. Environmental strains could cause infection, especially in immunocompromised patients; therefore, rare bacteria testing is required, in which identification special assistance is provided by an automated system MALDI-TOF

Electrical Pulse Stimulation of Cultured Human Skeletal Muscle Cells as an In Vitro Model of Exercise

Background and Aims Physical exercise leads to substantial adaptive responses in skeletal muscles and plays a central role in a healthy life style. Since exercise induces major systemic responses, underlying cellular mechanisms are difficult to study in vivo. It was therefore desirable to develop an in vitro model that would resemble training in cultured human myotubes. Methods Electrical pulse stimulation (EPS) was applied to adherent human myotubes. Cellular contents of ATP, phosphocreatine (PCr) and lactate were determined. Glucose and oleic acid metabolism were studied using radio-labeled substrates, and gene expression was analyzed using real-time RT-PCR. Mitochondrial content and function were measured by live imaging and determination of citrate synthase activity, respectively. Protein expression was assessed by electrophoresis and immunoblotting. Results High-frequency, acute EPS increased deoxyglucose uptake and lactate production, while cell contents of both ATP and PCr decreased. Chronic, low-frequency EPS increased oxidative capacity of cultured myotubes by increasing glucose metabolism (uptake and oxidation) and complete fatty acid oxidation. mRNA expression level of pyruvate dehydrogenase complex 4 (PDK4) was significantly increased in EPS-treated cells, while mRNA expressions of interleukin 6 (IL-6), cytochrome C and carnitin palmitoyl transferase b (CPT1b) also tended to increase. Intensity of MitoTracker®Red FM was doubled after 48 h of chronic, low-frequency EPS. Protein expression of a slow fiber type marker (MHCI) was increased in EPS-treated cells. Conclusions Our results imply that in vitro EPS (acute, high-frequent as well as chronic, low-frequent) of human myotubes may be used to study effects of exercise.This work was funded by the University of Oslo, Oslo University College, the Norwegian Diabetes Foundation, the Freia Chocolade Fabriks Medical Foundation and the Anders Jahre’s Foundation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Thermal investigation of acetochlor adsorption on inorganic- and organic-modified montmorillonite

Results presented in this paper are pioneering attempt toward better understanding of the thermal stability of acetochlor sorption in inorganic and organic montmorillonites. Changes in surface properties of acetochlor adsorbed on montmorillonites and montmorillonites modified with hexadecyltrimethylammonium bromide have been investigated by thermogravimetry, derivative thermogravimetry and infrared spectroscopy. The mass loss, as a result of the heating treatment, indicates release of free water, transformation of hydrophilic to hydrophobic surface, the release of acetochlor sorbed on the montmorillonite, the release of acetochlor sorbed on the montmorillonite and dehydroxylation of the structural OH units

The influence of Pb addition on the properties of fly ash-based geopolymers

Preventing or reducing negative effects on the environment from the waste landfilling is the main goal defined by the European Landfill Directive. Generally geopolymers can be considered as sustainable binders for immobilization of hazardous wastes containing different toxic elements. In this paper the influence of addition of high amount of lead on structure, strength, and leaching behavior (the effectiveness of Pb immobilization) of fly ash-based geopolymers depending on the geopolymer curing conditions was investigated. Lead was added during the synthesis of geopolymers in the form of highly soluble salt - lead-nitrate. Structural changes of geopolymers as a result of lead addition/immobilization were assessed by means of XRD, SEM/EDS, and Si-29 MAS NMR analysis. Investigated curing conditions significantly influenced structure, strength and leaching behavior of geopolymers. High addition of lead caused a sizeable decrease in compressive strength of geopolymers and promoted formation of aluminum-deficient aluminosilicate gel (de polymerization of aluminosilicate gel), regardless of the curing conditions investigated. According to the EUWAC limitations, 4% of lead was successfully immobilized by fly ash-based geopolymers cured for 28 days in a humid chamber at room temperature

A comparative analysis of stomata and leaf trichome characteristics in Quercus robur L. genotypes

The objective of this study was to determine genotype variability of leaf trichome and stoma characteristics. Leaves were sampled from seventeen pedunculate oak (Quercus robur L) genotypes originating from clonal seed orchard Banov Brod (Srem, the Vojvodina Province). The pedunculate oak has hypostomatal leaves. Statistically significant differences were found for the dimensions and density of stomata. Genotype variability of stomatal dimensions was less pronounced in comparison with their density (CV = 8.88%). Stomata number ranged from 530 to 791 per mm2 of leaf area; genotypes 18 and 25 could be distinguished from the others for the highest stomata number per leaf unit area, genotype 35 for the lowest number. In all genotypes, only solitary eglandular trichomes were observed on the adaxial leaf surface while both solitary eglandular and uniseriate glandular hairs were present on the abaxial surface. Single glandular trichomes were observed in all genotypes, while some of them were characterized by the presence of two (genotypes 4, 5, 6, 16, 22, 25, 28, 29, 30, 35, 38, 40, and 85) or three (genotypes 16, 25, 35) hairs joined by their basal cells

Heavy metal contamination of vegetables from green markets in Novi Sad

are valuable source of vitamins, minerals and fibers important for healthy human nutrition. However, an increased level of heavy metals in vegetables has been noticed in recent years. This study was conducted with an aim to analyze content of heavy metals, cadmium (Cd), lead (Pb), and chromium (Cr) in 11 vegetable species which are the most common in human diet. Vegetables were collected from three green markets (Limanska, Futoška and Riblja pijaca) in Novi Sad, during September and October, from 2009 to 2011. Heavy metal contents were analyzed in edible parts of tomato, potato, spinach, onion, beetroot, parsley, parsnip, carrot, cauliflower, pepper and broccoli using atomic absorption spectrophotometer (Varian, AAS 240FS). The results showed statistically significant differences in element concentrations among analyzed vegetables. In general, the highest metal pollution was observed in the year of 2011. Spinach was found to contain the highest metals content - 0.89 μg/g for Cd, 5.81 μg/g for Pb, and 3.67 μg/g for Cr. According to Serbian official regulations, 18.18% of all analyzed species exceeded maximum permissible level for Cd, 9.09% for Pb, while for Cr these limits are not defined. Elevated content of heavy metals in vegetables might be related to soil contamination, atmospheric depositions during transportation and marketing. Thus, a continuous monitoring of vegetables on markets should be performed in order to prevent potential health risks to consumers

Impact of sodium sulfate solution on mechanical properties and structure of fly ash based geopolymers

In this paper, geopolymers based on two different fly ash samples were exposed to sodium sulfate (Na2SO4) solution (50 g/l) over a period of 365 days. It was found that sulfate solution attack caused a small decrease in strength of geopolymer mortars. Analysis of the Na2SO4 solutions by optical emission spectroscopy indicated that exposing of the geopolymer samples to the Na2SO4 solution had caused leaching of one of the elements of the aluminosilicate gel, silicon. Mineralogical analyses of geopolymer samples did not show formation of any new phases due to a reaction with sulfate ions. Changes in aluminosilicate geopolymer gel due to sulfate attack were investigated by electron microscopy and nuclear magnetic resonance. It was found that treatment of geopolymer samples with the sulfate solution caused breaking of -Si-O-Si- bonds in aluminosilicate gel structure. Breaking of the -Si-O-Si- bonds and leaching of Si were consequences of the increase in the pH value of sulfate solution during testing

The influence of fly ash characteristics and reaction conditions on strength and structure of geopolymers

Reactivity of Class F fly ash (FA), development of strength, and structure of FA-based geopolymers, depending on the reaction conditions, were examined in this paper. The results of SEM/EDS and NMR analyses revealed that the composition of aluminosilicate gel changed during reaction, i.e. Si/Al atomic ratio decreased with the reaction time. Higher strength of geopolymers was associated with a higher fraction of aluminum rich structural units, higher crosslinking, and more compact structure. A rapid test for the assessment of FA reactivity and thus the applicability of FA for geopolymer synthesis was proposed