Cavitation, induced by ultrasound at low frequencies, is an effective means for the disintegration of bacterial cells. Two effects can be observed: At low ultrasound doses bacteria flocs can be declumped by mechanical shear stresses, and at increased doses ultrasound cavitation has an impact on the cell walls such that they are broken. In lab scale experiments a horn sonotrode operated at 20 kH...

Histotripsy is a therapy that focuses short-duration, high-amplitude pulses of ultrasound to incite a localized cavitation cloud that mechanically breaks down tissue. To investigate the mechanism of cloud formation, high-speed photography was used to observe clouds generated during single histotripsy pulses. Pulses of 5-20 cycles duration were applied to a transparent tissue phantom by a 1-MHz ...

Ultrasound treatment of liquid aluminum alloys is known to improve mechanical properties of castings. Aluminum foundry alloys are frequently used for production of parts that undergo severe cavitation erosion phenomena during service. In this paper, the effect of the ultrasound treatment on cavitation erosion resistance of AlSi7 alloy was assessed and compared to that of conventionally cast sam...

OBJECTIVE: Shock Wave Lithotripsy (SWL) is the use of shock waves to fragment kidney stones. We have undertaken a study of the physical mechanisms responsible for stone comminution and tissue injury in SWL. SWL was originally developed on the premise that stone fragmentation could be induced by a short duration, high amplitude positive pressure pulse. Even though the SWL waveform carries a prom...

background: various fixation and permeabilization techniques have been developed for detection of intracellular antigens by flow cytometry; however, there are few studies using flow cytometry to detect the frequency of intracellular nucleic acids, particularly rna. we tested six different permeabilization methods in order to gain access to a high quality method with minimal damage to intracellu...

Introduction: Mechanical index (MI) is used for quantifying acoustic cavitation and the relationship between acoustic pressure and the frequency. In this study, modeling of the MI was applied to provide treatment protocol and to understand the effective physical processes on reproducibility and gene expression of fibroblast cells. Skin damage can occur of burn, cuts, abrasions ...

BACKGROUND Mild-hyperthermia therapy (40-45 °C) with high-intensity focused ultrasound (HIFU) is a technique being considered in a number of different treatments such as thermally activated drug delivery, immune-stimulation, and as a chemotherapy adjuvant. Mechanical damage and loss of cell viability associated with HIFU-induced acoustic cavitation may pose a risk during these treatments or may...

Submit Manuscript | http://medcraveonline.com 100 kHz) can provide the mechanical effect of cavitation in liquid systems which can alter physical and chemical properties of food depending on the type of material involved. When ultrasound waves pass through a medium, a series of compression and rarefaction waves on the molecules of the medium are produced. This enforces a sinusoidal acoustic pre...

This paper presents an ultrasound piezoceramic transducer, centred into an extracorporeal shock wave lithotriptor system. The electromagnetic acoustic source lithotriptor initiates the incident shock waves into the water, and the ultrasound transducer improves the caviational effects of the bubbles. The piezoelectric transducer is powered by a Function/Pulse Generator type IWATSU SG-4511, and c...

BACKGROUND AND PURPOSE Ultrasound has been shown to increase recombinant tissue plasminogen activator thrombolysis through stable cavitation, or sustained bubble activity, but this mechanism needs further optimization. Use of low-frequency ultrasound in combination with microbubbles stabilized against dissolution, in the form of ultrasound contrast agents, has resulted in greater lytic efficacy...