東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

Development of Flexible Capacitive U...

Wentzell, Scott A.

Linked to FindBook

Google Book

Amazon

博客來

Development of Flexible Capacitive Ultrasound Transducers and the Use of Ultrasound for Bone Repair.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Development of Flexible Capacitive Ultrasound Transducers and the Use of Ultrasound for Bone Repair./
Author:	Wentzell, Scott A.
Description:	110 p.
Notes:	Source: Dissertation Abstracts International, Volume: 76-10(E), Section: B.
Contained By:	Dissertation Abstracts International76-10B(E).
Subject:	Biomedical engineering. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3705653
ISBN:	9781321789638

Development of Flexible Capacitive Ultrasound Transducers and the Use of Ultrasound for Bone Repair.
Wentzell, Scott A.

Development of Flexible Capacitive Ultrasound Transducers and the Use of Ultrasound for Bone Repair. - 110 p.

Source: Dissertation Abstracts International, Volume: 76-10(E), Section: B.

Thesis (Ph.D.)--Rensselaer Polytechnic Institute, 2015.

Ultrasound is a widely applicable technique for therapy in the biomedical arena. However, conventional ultrasound transducers are not conducive for non-planar surfaces. Therefore, we developed flexible transducers capable of performing ultrasound and evaluated their use in biomedical applications. Flexible capacitive ultrasound transducers based on micrometer-thick dielectric tapes were developed and fabricated. These transducers were able to be made by hand at low-cost while still demonstrating good tolerances in center operating frequency. Intensities of up to 120 mW/cm2 were recorded and operation was dependent upon the applied AC and DC voltages along with the thickness of the dielectric insulation. These capacitive ultrasound transducers were used to stimulate MC3T3-E1 murine osteoblast cells to investigate the effects of low-frequency ultrasound on osteogenic gene expression and anabolic signaling pathways. After stimulation by 94.5 kHz continuous wave ultrasound for 20 minutes, significant increases in the activation of the Wnt signaling pathway and concentration of intracellular calcium were observed. Daily stimulation by ultrasound showed a trend of increased osteogenic gene expression across the phases of matrix deposition, maturation and calcification by osteoblasts. Finally, the heating of osteoblasts for stimulating osteoclastogenic responses was investigated. The application of increased temperatures of 42 and 47 degrees Celsius for 5 minutes showed significant increases in the RANKL/OPG ratio in media conditioned by osteoblasts. However, the altered RANKL/OPG ratio was not able to generate increases in osteoclastogenesis for RAW 264.7 murine macrophage cells culture in the condition media. This was possibly due to high overall osteoprotegerin expression, or unwanted inducement of M1 and M2 macrophage activation in the cell population.

ISBN: 9781321789638Subjects--Topical Terms:

535387
Biomedical engineering.

Development of Flexible Capacitive Ultrasound Transducers and the Use of Ultrasound for Bone Repair.
LDR:03116nmm a2200289 4500 001 2064291
005 20151109142632.5
008 170521s2015 ||||||||||||||||| ||eng d
020 $a 9781321789638
035 $a (MiAaPQ)AAI3705653
035 $a AAI3705653
040 $a MiAaPQ $c MiAaPQ
100 1 $a Wentzell, Scott A. $3 3178856
245 1 0 $a Development of Flexible Capacitive Ultrasound Transducers and the Use of Ultrasound for Bone Repair.
300 $a 110 p.
500 $a Source: Dissertation Abstracts International, Volume: 76-10(E), Section: B.
500 $a Adviser: Shiva P. Kotha.
502 $a Thesis (Ph.D.)--Rensselaer Polytechnic Institute, 2015.
520 $a Ultrasound is a widely applicable technique for therapy in the biomedical arena. However, conventional ultrasound transducers are not conducive for non-planar surfaces. Therefore, we developed flexible transducers capable of performing ultrasound and evaluated their use in biomedical applications. Flexible capacitive ultrasound transducers based on micrometer-thick dielectric tapes were developed and fabricated. These transducers were able to be made by hand at low-cost while still demonstrating good tolerances in center operating frequency. Intensities of up to 120 mW/cm2 were recorded and operation was dependent upon the applied AC and DC voltages along with the thickness of the dielectric insulation. These capacitive ultrasound transducers were used to stimulate MC3T3-E1 murine osteoblast cells to investigate the effects of low-frequency ultrasound on osteogenic gene expression and anabolic signaling pathways. After stimulation by 94.5 kHz continuous wave ultrasound for 20 minutes, significant increases in the activation of the Wnt signaling pathway and concentration of intracellular calcium were observed. Daily stimulation by ultrasound showed a trend of increased osteogenic gene expression across the phases of matrix deposition, maturation and calcification by osteoblasts. Finally, the heating of osteoblasts for stimulating osteoclastogenic responses was investigated. The application of increased temperatures of 42 and 47 degrees Celsius for 5 minutes showed significant increases in the RANKL/OPG ratio in media conditioned by osteoblasts. However, the altered RANKL/OPG ratio was not able to generate increases in osteoclastogenesis for RAW 264.7 murine macrophage cells culture in the condition media. This was possibly due to high overall osteoprotegerin expression, or unwanted inducement of M1 and M2 macrophage activation in the cell population.
520 $a The overall work of this thesis demonstrates the development of novel capacitive transducers. These conformable devices have the potential to mediate both bone resorption and deposition, and also provide a new functional system for generating ultrasound on the irregular surfaces encountered in clinical settings.
590 $a School code: 0185.
650 4 $a Biomedical engineering. $3 535387
650 4 $a Acoustics. $3 879105
690 $a 0541
690 $a 0986
710 2 $a Rensselaer Polytechnic Institute. $b Biomedical Engineering. $3 3178857
773 0 $t Dissertation Abstracts International $g 76-10B(E).
790 $a 0185
791 $a Ph.D.
792 $a 2015
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3705653