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Bacterial biofilm formation is regarded as the major cause of infection development, therapeutic failure, and antibiotic resistance. This study aimed to assess the synergistic antibiofilm potential of an atmospheric-pressure non-thermal argon plasma and ciprofloxacin (Cip) against multi-drug-resistant Pseudomonas aeruginosa. Bacterial biofilms were pre-treated with the non-thermal Ar-plasma and subsequently treated with Cip antibiotic. Then, the bacterial biofilm formation level and cell viability were investigated using crystal violet staining, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide, SEM, and fluorescence microscopy, respectively. It was found that a short-time (a few seconds) pretreating with Ar-plasma not only reduced bacterial biofilm formation but also significantly decreased the viability of the cells within the biofilm matrix. According to the results, treating with Cip alone reduced bacterial biofilms by 32%, while pretreatment with Ar-plasma for 5, 10, 30, 60, and 90 s and subsequent treatment with Cip reduced bacterial biofilms by 76%, 79%, 81%, 75%, and 88%, respectively. In addition, the viability of bacterial cells within the biofilm matrix reduced to 66% in Cip treated cells, while pretreating with Ar-plasma for 5, 10, 30, 60, and 90 s and then treating with Cip significantly decreased cell viability to 28%, 25%, 21%, 23%, and 15%, respectively. This concept opens a promising approach for the treatment of drug-resistant bacteria for decontamination of heat-sensitive materials and human tissues based on the combination of atmospheric-pressure non-thermal Ar-plasma and antibiotics. [ABSTRACT FROM AUTHOR]

The effect of replacement of fish meal with AquPro on growth and enzymes activity on juvenile rainbow trout (weight: 2.38 ± 0.3 g) were evaluated. The fish were fed with five isoproteic and isocaloric diet for six weeks. The diets contained different level of replaced fish meal with Aqupro included 5 treatments (A= 0%), (B=25%), (C = 50%), (D=75%) and (E=100%). Based on the results ,weight gain, relative growth rate, protein and lipid efficiency ratio in diet 50% were significantly higher than other treatments (p< 0.05), while food efficiency ratio and feed conversion ratio were shown the highest and the lowest values in diet 50%, respectively , without a significant difference than those from other treatments (p> 0.05). The highest survival rate was revealed in the diet 75%, which was not affected by the level of AquPro in the diet. The highest activity of lipase, amylase and acid protease enzymes, respectively, from pyloric caeca, intestine and stomach were observed in diet 50%, which showed a significant difference compared to other diets (p< 0.05). The findings of growth performance and lipase, amylase and acid protease activity were revealed the diet containing 50% AquPro could be appropriate for rainbow trout growth

Nanocrystalline TiO2 coatings were produced on titanium substrates using the plasma electrolytic oxidation technique. The effects of frequency, duty cycle, and type of applied current (pulse and direct) were evaluated on the microstructure of the coatings and the tribological behavior of the samples. Morphological evaluations demonstrated that the pancake structure was developed from coatings created with a unipolar pulsed current. However, a volcano-like surface morphology resulted from a constant current. The XRD analysis results showed that the coatings were composed mainly of the rutile phase by 77.80-96.34 wt. %. In comparison, 22.20 wt. % of the anatase phase was identified in samples produced with direct current. These phases were determined to be nanocrystalline (29.5-48.3 nm), which led to significant improvements in the tribological properties. The sample produced with direct current had larger pores, greater roughness, and a four-times higher thickness than samples created with unipolar current. Furthermore, the tribological study results showed that wear resistance was significantly higher in the unipolar pulsed current coatings than in those obtained with direct current. Moreover, samples made at a higher frequency and lower duty cycle showed better tribological behavior. [ABSTRACT FROM AUTHOR]

Beetroot juice (BRJ) has become increasingly popular amongst athletes aiming to improve sport performances. BRJ contains high concentrations of nitrate, which can be converted into nitric oxide (NO) after consumption. NO has various functions in the human body, including a vasodilatory effect, which reduces blood pressure and increases oxygen- and nutrient delivery to various organs. These effects indicate that BRJ may have relevant applications in prevention and treatment of cardiovascular disease. Furthermore, the consumption of BRJ also has an impact on oxygen delivery to skeletal muscles, muscle efficiency, tolerance and endurance and may thus have a positive impact on sports performances. Aside from the beneficial aspects of BRJ consumption, there may also be potential health risks. Drinking BRJ may easily increase nitrate intake above the acceptable daily intake, which is known to stimulate the endogenous formation of N-nitroso compounds (NOC's), a class of compounds that is known to be carcinogenic and that may also induce several other adverse effects. Compared to studies on the beneficial effects, the amount of data and literature on the negative effects of BRJ is rather limited, and should be increased in order to perform a balanced risk assessment. [ABSTRACT FROM AUTHOR]

To fully appreciate the role and application of composite materials to structures, correct understanding of mechanical behaviors required for selection of optimum material. Fabric reinforced composites are composed of a matrix that is reinforced with pliable fabric, glass fabric is most popular reinforcement for different application specially in aircraft structure, although other fabric material are also used. At this study new fabric material called basalt with epoxy resin introduced and mechanical behaviors of this material investigated from view point of testing. For this study two type of fabric with different thickness used. Comparison between this composite reinforcement with popular reinforcement as carbon, glass, kevlar performed. To determine mechanical properties of epoxy based basalt fabric following test procedure performed : 1). Tensile testing according to ASTM D3039 in 0° and 90° direction to find ultimate strength in tension and shear, modulus of elasticity, elangation and ultimate strain. 2). Compression testing according to EN 2850 ultimate compression strength and maximum deformation under compression loading. 3). Shear testing according to ASTM D3518-94 to find in plane shear response of polymer matrix composites materials. 4). Predict flexural properties of sandwich construction which manufactured from basalt facing with PVC foam core according to ASTM C393-94. Material strength properties must be based on enough tests of material to meet the test procedure specifications [1]. For this reason six specimens were manufactured for testing and the tests were performed on them using an INSTRON machine model 5582. In the study, the effect of percent of resin in basalt reinforced composite was investigated. Also the weights of the ballast based composites with different percent of resin were measured with conventional composites. As the weight is an important parameter in aerospace industry when the designer wants to replace one material with another, the effect of weight must be considered. Weight measurement showed that the replacement of glass fabric reinforcement with basalt fabric has little effect on weight. Investigation also shows that mechanical behavior of basalt fabric is higher than glass fabric. This is due to the excellent mechanical properties of the ballast fabric such as Young modulus and strength in compare with the glass fabric. Figure1 shows the samples which used for tensile testing in warp direction.

The aim of this study was to systematically review the literature on fetal cardiac function, assessed with two-dimensional speckle-tracking echocardiography (2D-STE) in fetuses of mothers with diabetes in comparison to those of mothers without diabetes. RV-GLS values were increased (6 studies), decreased (1 study) or not different (1 study). In fetuses of mothers with diabetes versus mothers without diabetes, LV-GLS values were significantly increased (6 studies), decreased (1 study) or not significantly different (6 studies). [Extracted from the article]

In this paper, vibration suppression of shear deformable beams with hybrid material-foundation viscoelastic damping is studied. The precise behavior of viscoelastic polymeric structures is taken into consideration by Boltzmann superposition integral and utilizing dynamic mechanical analysis (DMA) results while foundation viscoelasticity is adapted by Kelvin-Voigt model. The integro-partial differential equations of motion are derived based on the Timoshenko theory via Hamilton principle. Assessment of the solution procedure is carried out by comparison with elastic Timoshenko and viscoelastic Euler-Bernoulli cases. Transient response, natural frequency and modal loss factor are attained by Fourier transform, weighted residual method and numerical iterative algorithm. Influences of hybrid viscoelastic damping, foundation properties, geometrical parameters and boundary conditions on vibration characteristics and dynamic response are investigated via comprehensive parametric study. Due to the absence of similar results in the literature, this paper is likely to fill a gap in the state of the art of this problem. [ABSTRACT FROM AUTHOR]

SnSbO (0 ≤ x ≤0.1) nanoparticles were synthesized by chemical solution method using organic solvent. Antibacterial and photocatalytic activities of the prepared nanoparticles were discussed based on structural, compositional and optical properties. The X-ray diffraction patterns indicated that the Sb doping decreased the crystallite size and lattice parameters of SnO nanoparticles while the compressive strain and dislocation density of cassiterite phase increased. The X-ray photoelectron spectroscopy spectra of SnSbO confirmed that Sb ions substituted at Sn sites with +5 valance state. Field emission scanning electron microscopy showed that the nanoparticles possess spherical shape and Sb doping decreased the grain size. UV-Vis absorption spectra revealed that the substitution of Sb in SnO lattice leads to band gap narrowing from 4.06 to 3.85 eV. Photoluminscence spectra of SnSbO nanoparticles disclosed a green emission due to the presence of oxygen vacancies and SnSbO had highest emission intensity among all samples. The SnSbO nanoparticles exhibited enhanced photodegradation of rhodamine B and methylen blue dyes under UV illumination compared to the undoped SnO. The bactericidal activity of SnSbO nanoparticles was investigated against bacterial pathogens including E. coli, P. aeruginosa, and S. aureus. The results revealed that antibacterial and photocatalytic activities of nanoparticles strongly depend on reactive oxygen species and structural parameter of the nanoparticles. [ABSTRACT FROM AUTHOR]

In the present study the fuel spray of a gasoline direct injected engine with multi-hole injector is simulated. Simulation inputs data, injection flow rate and spray cone angle are obtained from previous experimental studies. Log-normal distribution with different standard deviation is used for initial droplet size as the primary break-up model in order to reach the agreement between experimental and calculated spray tip penetration. As the first step, only one plume of spray injected into a quiescent air environment is simulated and validated by varying break-up model and standard deviation. Then, with coefficient obtained from the single jet simulation all six spray jets are simulated based on the injector nozzles geometry. The comparison between single-jet simulation and multi-jet simulation shows that validated model coefficients for the single-jet spray cannot be used for multi-jet spray simulation without significant modifications due to adjacent jet interaction and pressure drag. A set of new coefficients for the multi-jet spray is presented. [ABSTRACT FROM AUTHOR]