BIOACTIVE COMPOUNDS AND ANTIOXIDANT CHARACTERISTICS OF VARIOUS TOMATO CULTIVARS FROM SERBIA – CHEMOMETRIC APPROACH

Tomato is one of the most consumed foodstuffs around the world and major dietary source of lycopene. The main objectives of this study were evaluation of antioxidant activity, using DPPH, ABTS, FRAP, TRP and CUPRAC assays, as well as total phenolic, total flavonoid, lycopene and β-carotene content in 30 tomato and cherry tomato cultivars commonly consumed in Serbia. Tomato with the highest total phenol and total flavonoid content was tomato Indigo Rose (17.56 mg GAE g-1 DW and 30.30 mg RE g-1 DW, respectively), which showed excellent antioxidant characteristics. Total lycopene content was lower in yellow tomato species compared to the red ones, and the highest lycopene content was 0.283 mg g-1 DW for tomato Red Pearl Big. Cluster analysis yields dendrogram, separating tomato and cherry tomato cultivars into three statistically significant clusters ((Dlink / Dmax)×100 < 50)

Optimization of technological procedure for amygdalin isolation from plum seeds (Pruni domesticae semen)

The process of amygdalin extraction from plum seeds was optimized using central composite design (CCD) and multilayer perceptron (MLP). The effect of time, ethanol concentration, solid-to-liquid ratio, and temperature on the amygdalin content in the extracts was estimated using both mathematical models. The MLP 4-3-1 with exponential function in hidden layer and linear function in output layer was used for describing the extraction process. MLP model was more superior compared with CCD model due to better prediction ability. According to MLP model, the suggested optimal conditions are: time of 120 min, 100% (v/v) ethanol, solid-to liquid ratio of 1:25 (m/v) and temperature of 34.4 degrees C. The predicted value of amygdalin content in the dried extract (25.42 g per 100 g) at these conditions was experimentally confirmed (25.30 g per 100 g of dried extract). Amygdalin (>90%) was isolated from the complex extraction mixture and structurally characterized by FT-IR, UV, and MS methods

Surgical site infection incidence and risk factors in thoracic surgical procedures: A 12-year prospective cohort study

Introduction: Surgical site infections (SSI) continue to be a major problem for thoracic surgery patients. We aimed to determine incidence rate (IR) and risk factors for SSI in patients with thoracic surgical procedures. Methodology: During 12 years of hospital surveillance of patients with thoracic surgical procedures, we prospectively identified SSI. Patients with SSI were compared with patients without SSI. Results: We operated 3,370 patients and 205 (6.1%) developed SSI postoperatively. We detected 190 SSI among open thoracic surgical procedures (IR 7.1%) and 15 SSI after video-assisted thoracic surgery (IR 2.1%). Five independent risk factors for SSI were identified: wound contamination (p = 0.013; relative risk (RR) 2.496; 95%, confidence interval (CI): 1.208-5.156), American Society of Anesthesiologist (ASA) score (p = 0.012; RR: 1.795; 95% CI: 1.136-2.834), duration of drainage (p < 0.001; RR: 1.117; 95% CI: 1.085-1.150), age (p = 0.036; RR: 1.018; 95% CI: 1.001-1.035) and duration of operation (p < 0.001; RR:1.005; 95% CI:1.002-1.008). Conclusion: The results are valuable in documenting risk factors for SSI in patients undergoing thoracic surgery. The knowledge and prevention of controllable risk factors is necessary in order to reduce the incidence of SSI

Discutindo a educação ambiental no cotidiano escolar: desenvolvimento de projetos na escola formação inicial e continuada de professores

A presente pesquisa buscou discutir como a Educação Ambiental (EA) vem sendo trabalhada, no Ensino Fundamental e como os docentes desta escola compreendem e vem inserindo a EA no cotidiano escolar., em uma escola estadual do município de Tangará da Serra/MT, Brasil. Para tanto, realizou-se entrevistas com os professores que fazem parte de um projeto interdisciplinar de EA na escola pesquisada. Verificou-se que o projeto da escola não vem conseguindo alcançar os objetivos propostos por: desconhecimento do mesmo, pelos professores; formação deficiente dos professores, não entendimento da EA como processo de ensino-aprendizagem, falta de recursos didáticos, planejamento inadequado das atividades. A partir dessa constatação, procurou-se debater a impossibilidade de tratar do tema fora do trabalho interdisciplinar, bem como, e principalmente, a importância de um estudo mais aprofundado de EA, vinculando teoria e prática, tanto na formação docente, como em projetos escolares, a fim de fugir do tradicional vínculo “EA e ecologia, lixo e horta”.Facultad de Humanidades y Ciencias de la Educació

Influence of SnO2 Content on the Humidity Dependent Impedance of the MgFe2O4-Fe2O3-SnO2 Compound

A porous MgFe2O4-Fe2O3-SnO2 bulk compound with varying SnO2 content was obtained by sintering an appropriate mixture of magnesium oxide, hematite and tin oxide nanopowders at 1000 and 1100 °C. The obtained structure was confirmed by X-ray diffraction analysis. Scanning electron microscopy was used to analyze sample morphology, showing that the addition of SnO2 resulted in an inhomogeneous microstructure with smaller grain size especially at 1000 °C. Significant grain growth of hematite grains was noted at 1100 °C. The influence of relative humidity in the range 30–90% was monitored at room temperature (25 °C) in the frequency range 42 Hz- 1 MHz. The highest reduction of impedance with humidity was noted at lower frequency. Addition of low amounts of SnO2 and sintering at 1000 °C resulted in the highest sensitivity at 105 Hz of 0.391 MΩ/%RH in the RH30–90% range, while the compound with the highest amount of SnO2 showed the largest decrease in impedance with increase in relative humidity ~26 times. All samples showed low hysteresis (below 2%). Complex impedance data was analyzed using equivalent circuits reflecting the dominant influence of the grain boundary in the lower relative humidity range (30–60%) and both grain boundary and grain components in the higher relative humidity range (60–90%).</jats:p

Effect of the anodic current density on copper electrodeposition in the hydrogen co-deposition range by the reversing current (RC) regime

In this study, the effect of the anodic current density in the regime of reversing current (RC) on the quantity of evolved hydrogen and morphology of copper deposits was considered. The quantity of evolved hydrogen was quantified by the determination of the average current efficiency for hydrogen evolution reaction, while morphology and internal structures of electrodeposited copper were analyzed using scanning electron (SEM) and optical microscopy techniques, respectively. In all RC experiments, the cathodic current density of 440 mA/cm(2), cathodic pulse of 10 ms and anodic pulse of 5 ms were applied, while the analyzed anodic current densities were: 40, 240, 440 and 640 mA/cm(2). The number, size and shape of holes formed of detached hydrogen bubbles strongly depended on the selected parameters of square waves RC. Due to the decrease of the quantity of evolved hydrogen with the increasing anodic current density, the change of morphology of copper deposits formed around holes from cauliflower-like agglomerates of copper grains to dendrites was observed. Honeycomb-like structures were formed with the anodic current density values up to 440 mA/cm(2). The compactness of the honeycomb-like structures increased with the increase of the anodic current density. The improvement of structural characteristics of the honeycomb-like electrodes was achieved by the application of the RC regime in comparison with both the pulsating current (PC) and constant galvanostatic regimes. It was found that the regime of reversing current is superior in the production of the honeycomb-like electrodes in relation to other current regimes of electrolysis. (C) 2011 Elsevier B.V. All rights reserved

The development of a new inhibition kinetic spectrophotometric method for determination of phenylhydrazine

Anew sensitive kinetic method has been developed for the determination of trace amounts of phenylhydrazine in the range of 1.08×10-7 to 1.08×10-6 g/cm3. The detection limit of this method is 0.008 mg/cm3, based on the 3Sb criterion. Themethod is based on the inhibitory effect of phenylhydrazine on the oxidation of Victoria Blue 4-R by KBrO3. The reaction was monitored spectrophotometrically at 596.3 nm. The method development includes the optimization of the reagent concentration and temperature. The kinetic parameters of the reaction are reported and a rate equation is suggested. The effects of certain foreign ions upon the reaction rate were determined for the assessment of the selectivity of the method. The new developedmethod was found to have fairly good selectivity, sensitivity, simplicity and rapidity