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In this work, the so-called natural or passive ventilation drag reduction method is investigated experimentally and numerically. Passive ventilation is performed by directly connecting the high pressure region at the front of a body to the lower pressure in the near wake using a venting duct; in this manner, a net mass flux is established within the wake. In particular, in aerodynamic applications it appears suitable to attain a global reduction in the drag of a body moving in a fluid and a reduction in turbulence levels by means of a global modification of the body wake. Velocity field investigations using particle image velocimetry measurements and a Reynolds averaged numerical code are employed at moderately high Reynolds numbers to clarify the effectiveness of drag reduction on a vented bluff body. The numerical and experimental results agree qualitatively, but the amount of reduction for the vented body (about 10%) is underestimated numerically. The effectiveness of drag reduction has been proved both for smooth and rough (single strip) models. Direct balance measurements are used for comparisons. [ABSTRACT FROM AUTHOR]

Tomato (Lycopersicon esculentum) is a vegetable rich in antioxidants, such as lycopene, lutein, and zeaxanthin. Their presence is responsible for the characteristic ability of this product to inhibit the formation of reactive oxygen species, including singlet oxygen. The grapes and wines derived from grapes also contain powerful antioxidants. The antioxidant effect is derived from the polyphenols such as resveratrol and proanthocyanidin. Resveratrol is phytoalexin that is synthesized via the activation of the gene, stilbene synthase (STS). We decided to determine if the introduction of this gene into Lycopersicon esculentum Mill could modify its antioxidant activity. Using Electronic Paramagnetic Resonance (EPR) spectroscopy, which permits the detection of antiradical activity, especially •OH (hydroxyl radical), we showed that the antioxidant activity of the products, into which the gene STS had been introduced, was almost double than that of natural products and that their activity was especially pronounced due to ripening. Moreover, resveratrol concentrations in modified tomatoes were much higher than that found in the individual fruit. In the isolated hearts subjected to ischemia/reperfusion, the rats fed with modified tomato exhibited better cardiac performance, reduced myocardial infarct size and decreased number of apoptotic cardiomyocytes, and reduced oxidative stress compared to unmodified tomato or resveratrol alone indicating superior cardioprotective abilities of modified tomatoes. [ABSTRACT FROM AUTHOR]

Herein we provided the first proof of principle for in vivo fluorescence optical imaging application using monoolein-based cubosomes in a healthy mouse animal model. This formulation, administered at a non-cytotoxic concentration, was capable of providing both exogenous contrast for NIR fluorescence imaging with very high efficiency and chemospecific information upon lifetime analysis. Time-resolved measurements of fluorescence after the intravenous injection of cubosomes revealed that the dye rapidly accumulated mainly in the liver, while lifetimes profiles obtained in vivo allowed for discriminating between free dye or dye embedded within the cubosome nanostructure after injection. [ABSTRACT FROM AUTHOR]