Methane Sulfonation via a Free-Radical Mechanism by Trifluoroacetylsulfuric Acid.

Using trifluoroacetyl sulfuric acid (TFAOSOH), we discovered a new methane activation method and revealed its radical pathway under mild conditions. Upon the addition of a radical initiator with methane, the crude solution of TFAOSOH developed the methyltrifluoroacetylsulfate radical ((TFAO)CHS(OH)O•). The resulting (TFAO)CHS(OH)O• behaved as a critical radical propagator for carbon-hydrogen bond activation, culminating in successful methane sulfonation.

Enhancement of Cardiomyogenesis in Murine Stem Cells by Low-Intensity Ultrasound.

Objectives: Low-intensity ultrasound (LIUS) has been shown to enhance bone and cartilage regeneration from stem cells. The ease of its incorporation makes it an attractive mechanical stimulus for not only osteogenesis and chondrogenesis, but also cardiomyogenesis. However, to date, no study has investigated its effects on cardiomyogenesis from embryonic stem cells.

Shifting the Split Reflectors to Enhance Stone Fragmentation of Shock Wave Lithotripsy.

Shock wave lithotripsy (SWL) has been used widely in urology for about three decades to treat kidney calculi. Technical development to improve performance (i.e.

Suppressing bubble shielding effect in shock wave lithotripsy by low intensity pulsed ultrasound.

Extracorporeal shock wave lithotripsy (ESWL) has been used as an effective modality to fragment kidney calculi. Because of the bubble shielding effect in the pre-focal region, the acoustic energy delivered to the focus is reduced. Low pulse repetition frequency (PRF) will be applied to dissolve these bubbles for better stone comminution efficiency.

Reducing lesion aberration by dual-frequency focused ultrasound ablations.

Discrepancies between hyperecho-predicted necrosed volume in ultrasound (US) images and the actual size of a thermal lesion might cause incomplete ablation or damage normal structures during high intensity focused US (HIFU) ablations. A novel dual-frequency sonication procedure is proposed to reduce this discrepancy. HIFU transducers of either 1 or 3.

Single-element ultrasound transducer for combined vessel localization and ablation.

This report describes a system that utilizes a single high-intensity focused ultrasound (HIFU) transducer for both the localization and ablation of arteries with internal diameters of 0.5 and 1.3 mm.