Dynamics of an oscillating microbubble in a blood-like Carreau fluid.

A numerical model for cavitation in blood is developed based on the Keller-Miksis equation for spherical bubble dynamics with the Carreau model to represent the non-Newtonian behavior of blood. Three different pressure waveforms driving the bubble oscillations are considered: a single-cycle Gaussian waveform causing free growth and collapse, a sinusoidal waveform continuously driving the bubble, and a multi-cycle pulse relevant to contrast-enhanced ultrasound. Parameters in the Carreau model are fit to experimental measurements of blood viscosity.

Characterizing viscoelastic materials via ensemble-based data assimilation of bubble collapse observations.

Viscoelastic material properties at high strain rates are needed to model many biological and medical systems. Bubble cavitation can induce such strain rates, and the resulting bubble dynamics are sensitive to the material properties. Thus, in principle, these properties can be inferred via measurements of the bubble dynamics.

Acoustic Measurements of Nucleus Size Distribution at the Cavitation Threshold.

An understanding of the acoustic cavitation threshold is essential for minimizing cavitation bio-effects in diagnostic ultrasound and for controlling cavitation-mediated tissue ablation in focused ultrasound procedures. The homogeneous cavitation threshold is an intrinsic material property of recognized importance to biomedical ultrasound as well as a variety of other applications requiring cavitation control. However, measurements of the acoustic cavitation threshold in water differ from those predicted by classic nucleation theories.

Single-bubble dynamics in histotripsy and high-amplitude ultrasound: Modeling and validation.

A variety of approaches have been used to model the dynamics of a single, isolated bubble nucleated by a microsecond length high-amplitude ultrasound pulse (e.g. a histotripsy pulse).

Modeling tissue-selective cavitation damage.

The destructive growth and collapse of cavitation bubbles are used for therapeutic purposes in focused ultrasound procedures and can contribute to tissue damage in traumatic injuries. Histotripsy is a focused ultrasound procedure that relies on controlled cavitation to homogenize soft tissue. Experimental studies of histotripsy cavitation have shown that the extent of ablation in different tissues depends on tissue mechanical properties and waveform parameters.

Comparative study of the dynamics of laser and acoustically generated bubbles in viscoelastic media.

Experimental observations of the growth and collapse of acoustically and laser-nucleated single bubbles in water and agarose gels of varying stiffness are presented. The maximum radii of generated bubbles decreased as the stiffness of the media increased for both nucleation modalities, but the maximum radii of laser-nucleated bubbles decreased more rapidly than acoustically nucleated bubbles as the gel stiffness increased. For water and low stiffness gels, the collapse times were well predicted by a Rayleigh cavity, but bubbles collapsed faster than predicted in the higher stiffness gels.

Computational analysis of the fructosyltransferase enzymes in plants, fungi and bacteria.

Fructosyltransferases (FTases) are enzymes produced by plants, fungi, and bacteria, which are responsible for the synthesis of fructooligosaccharides. In this study, we conducted a computational analysis of reported sequences for FTase from a diverse source of organisms, such as plants, fungi, and bacteria. Ninety-one proteins sequences were obtained; all belonging to the glycoside hydrolase 32 (GH32) and 68 (GH68) families.

Recent trends in fructooligosaccharides production.

Prebiotics are food ingredients that promote host health beneficially due to their effect over the growth and activity of probiotic bacterial species. Prebiotic properties have been demonstrated for inulin-type fructans, galactoolicosaccharides and lactulose. Fructooligosaccharides (FOS), considered as inulin-type fructans, represent an important source of prebiotic compounds that are widely used as an ingredient in functional foods.

Gene cloning and enzyme structure modeling of the Aspergillus oryzae N74 fructosyltransferase.

The fructooligosaccharides (FOS) represent an important source of prebiotic compounds that are widely used as an ingredient in functional foods. Recently, the strain Aspergillus oryzae N74 was reported as a potential microorganism for the industrial production of FOS, due to its high yields of FOS production. In this work, we used a PCR-cloning strategy to clone the A.

[Mood state indicators for adolescent athletes based on POMS multidimensional model].

In this paper, we offer a short version of the POMS, with only 33 items, designed to apply to young Spanish athletes. One hundred and six male soccer players, aged 14 and 15 years, participated in the study. In order to select the proposed items, we tried to maximize three criteria: (1) items should be understood by subjects, (2) items should be perceived as conceptually similar as possible to the meaning of their respective factors, and (3) every factor should contain at least 4 items.