• Journal of Korean Society of Water and Wastewater
• /
• v.26 no.2
• /
• pp.313-319
• /
• 2012

This study investigated the relative degradation of commonly known endocrine-disrupting compounds such as bisphenol A (BPA) and 17${\beta}$-estradiol (E2) using ultrasound (US) and pulsed ultraviolet (PUV) in water. The removal efficiency of BPA and E2 was determined as a function of generating power and $H_{2}O_{2}$ production. The ultrasound and PUV irradiation of the aqueous solution was performed in 3 L and 90 L stainless reactor at a constant temperature of $20^{\circ}C$ with an applied power of 200 W and 2000 W, respectively. The removal of BPA and E2 by US and PUV varied with catalysts. The experiments were conducted under the following conditions: total operating time, 30 min; initial concentration, 1 uM. In the case of E2 (10 min), % removal was 92.5/95.8/87.6/82.4, while % removal of BPA (10 min) was 62.3/82.3/91.1/67.0/64.3 in various conditions (PUV, $PUV+H_2O_2$, PUV+wire mesh, $PUV+TiO_2$ coated wire mesh), respectively.

• Journal of dental hygiene science
• /
• v.14 no.2
• /
• pp.101-106
• /
• 2014

In this study, we investigated the proliferative and adhesional effect of human osteoblast like MG-63 cell treated with low intensity pulsed ultrasound (LIPUS). We tested the effectiveness of LIPUS in human osteoblast like MG-63 cells. Cell proliferation was measured using a water soluble tetrazolium salts-1 assay. The mRNA expression of alkaline phosphate, vascular endothelial growth factor (VEGF), integrin alpha 2, colla 1A1 were performed by reverse transcription-polymerase chain reaction. LIPUS was no cytotoxicity in human osteoblast like MG-63 cells. In addition, the data show that treatment with 1 MHz and 3 MHz LIPUS on increased proliferation 7 days after. There were significant increased in mRNA expression of alkaline phosphatase, osteocalcin, VEGF, integrin alpha 2 and colla 1A1 (p<0.05). Therefore, the LIPUS significantly increased differential expression of mRNA levels in osteoblast like MG-63 cell and new possibilities in dental clinical practice.

• The Korean Journal of Pain
• /
• v.35 no.2
• /
• pp.183-190
• /
• 2022

Background: To compare ultrasound-guided pulsed radiofrequency (PRF) of the genicular nerve with the genicular nerve block using local anesthetic and steroid for management of osteoarthritis (OA) knee pain. Methods: Thirty patients with OA knee were randomly allocated to receive either ultrasound-guided PRF of the genicular nerve (PRF group) or nerve block with bupivacaine and methylprednisolone acetate (local anesthetic steroid [LAS] group). Verbal numeric rating scale (VNRS) and Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) scores were measured at pre-procedure and 1-, 4-, and 12-weeks post-procedure. Results: VNRS scores decreased significantly (P < 0.001) in both the groups at 12 weeks and other follow up times compared to baseline. Seventy-three percent of patients in the PRF group and 66% in the LAS group achieved effective pain relief (≥ 50% pain reduction) at 12 weeks (P > 0.999). There was also a statistically significant (P < 0.001) improvement in WOMAC scores in both groups at all follow up times. However, there was no intergroup difference in VNRS (P = 0.893) and WOMAC scores (P = 0.983). No complications were reported. Conclusions: Both ultrasound-guided PRF of the genicular nerve and blocks of genicular nerve with local anesthetic and a steroid provided comparable pain relief without any complications. However, PRF of the genicular nerve is a procedure that takes much more time and equipment than the genicular nerve block.

• Current Optics and Photonics
• /
• v.2 no.1
• /
• pp.59-68
• /
• 2018

Opto-acoustic systems provide structural and functional information regarding biological tissues. Conventional opto-acoustic systems typically employ continuous or pulsed lasers as transmission sources. Compared to lasers, light emitting diodes (LEDs) are cost-effective and relatively portable excitation sources but are non, coherent. Therefore, in this study, a relatively low cost lens - a type of Ramsden eyepiece - was specially designed to theoretically calculate the illumination and achieve a constant brightness across the pupil of an eye. In order to verify the capability of the developed light-emitting diode-acoustic (LEDA) systems, we carried out experiments on bovine and bigeye tuna eyeball samples, which are of similar size to the human eye, using low frequency (10 MHz) and high frequency (25 MHz) ultrasound transducers. High frequency ultrasound transducers are able to provide higher spatial resolution compared to low frequency ultrasound transducers at the expense of penetration depth. Using the 10 MHz and 25 MHz ultrasound transducers, acceptable echo signals (3.82, 3.94, and 5.84 mV at 10 MHz and 282, 1557, 2356 mV at 25 MHz) from depth greater than 3 cm and 6 cm from the anterior surface of the eye were obtained. We thereby confirmed that the LEDA system using a pulsed LED with the designed Ramsden eyepiece lens, used in conjunction with low and high frequency ultrasound transducers, has the potential to be a cost-effective alternative method, while providing adequate acoustic signals from bovine and bigeye tuna ocular areas.

• Korean Journal of Head & Neck Oncology
• /
• v.17 no.1
• /
• pp.19-25
• /
• 2001

Objectives: The clinical efficacy of the color and pulsed Doppler ultrasound with spectral waveform analysis for differentiation of malignant from benign cervical lymphadenopathy was prospectively evaluated in cervical lymphadenopathy. Materials and Methods: Color and pulsed Doppler ultrasound examination was prospectively performed in 32 cervical lymph nodes in 28 patients. These 10 nodes from 10 patients were malignant and 22 nodes from 18 patients were benign, proved by operation, biopsy, and follow-up examination. Another 12 lymph nodes from 12 normal volunteers were evaluated as control group. The peak systolic velocity (PSV), minimal diastolic velocity (MDV) , and resistive indexes (RI) of arterial flows within the 32 lymph nodes were assessed to differentiate the malignant from benign nodes with pulsed Doppler ultrasonography. The results were qualitified with one-way ANOVA and Bonferroni method of multiple comparison. Results: The mean values of PSV of malignant, benign, and control nodes were 38.2(10.1-134)cm/sec, 23.3(9-38.5) cm/sec and 11.8(6.7-18.1) cm/sec, respectively. The mean values of MDV of them were 0.9(-7.5-10.7)cm/sec, 9.7(2.9-18.6)cm/sec and 6.5(3.7-9.3)cm/sec, respectively. However, there was no statistical significance in differentiation of malignant from benign nodes with PSV and MDV. The mean values of RI of malignant, benign, and control nodes were 0.99(0.80-1.30), 0.59(0.46-0.77) and 0.45(0.38-0.50), respectively. RI value of 0.8 is suggestive value for discrimination of malignant from benign lymphadenopathy during examination of color Doppler ultrasound of cervical lymphadenopathy. Conclusion: Color and pulsed Doppler ultrasound examination with spectral waveform analysis may be quite helpful in the differentiation between benign and malignant alterations of cervical lymph nodes.

• Proceedings of the KIEE Conference
• /
• 1988.07a
• /
• pp.297-300
• /
• 1988

The ultrasound Doppler effect is used for measuring the velocity of the bloodflow in an artry. Because of the range information, the pulsed doppler system is most commonly used. In this paper, we propose a new pulsed doppler system which uses a quadrature sampling method in R.F. range in order to detect the bloodflow direction and to simplify the compexity of hardware. The pulsed doppler system using quadrature sampling method in R.F. range eliminates In-phase, Quadrature phase channel balancing problem at demodulator. In addition, the improved pulsed Doppler system shows the possibility of serial processing.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.23 no.3
• /
• pp.389-396
• /
• 1986

A pulsed ultrasonic doppler flowmeter for mesurements of velocity profils in man is described. The device projects a beam of ultrasound in burst of 570 ns duration at 3.5 MHz. The back-scattered signals are processed to produce a signal oxrresponding to the mean velocity over a small region of the flowing stream. The observation range of 112mm is divided into 128 depth channels. The size of this sample volume determines the flowmeter sensitivity and accuracy. The device uses a quadrature detector to detect the direction of the moving target(hemoglobin). The main feature of the novel instrumnet is its simple hardware structure due to sequential signal processing.

• Proceedings of the KOSOMBE Conference
• /
• v.1992 no.11
• /
• pp.43-46
• /
• 1992

$\underline{In\;vitro}$ velocity measurements were made using both the pulsed Doppler ultrasound (PDU) machine and laser Doppler anemometer (LDA) system in order to investigate the flow characteristics near the aortic bifurcation. Velocities measured from the PDU machine was in good agreement with those from the LDA. The flow in the daughter branches was three-dimensional with a secondary flow. The oscillating wall shear stress with this secondary fluid motion is well correlated with the localization of the atherosclerosis.

• Proceedings of the KOSOMBE Conference
• /
• v.1995 no.05
• /
• pp.15-18
• /
• 1995

Three-dimensional steady and pulsatile flow experiments and numerical simulations have conducted to investigate the flow characteristics in the aortic bifurcation model. In vitro velocity measurements were made using both laser Doppler anemometry and pulsed Doppler ultrasound velocimetry. In this study, flow phenomena in the aortic bifurcation model are discussed extensively and the numerical results are compared with experimental results.

• The Journal of Korean Physical Therapy
• /
• v.14 no.4
• /
• pp.147-162
• /
• 2002

Transdermal permeation enhancer has been used to increased skin absorption. External control of drug release and skin absorption can also be achieved by iontophoresis or phonophoresis. However, because several problems with iontophoresis are that it has a risk to skin damage because of the change of pH and the increase of current density in applying it and that it can be applied only in the form of water solution, This study is to enhance drug permeation via skin following application of ultrasound. For this goal, in gel containing piroxicam, the degree of skin permeation in vitro and anti-inflammatory effect in in vivo were investigated. Permeation study using hairless mouse skin was performed at 37 $^{\circ}C$ using buffer saline as the receptor solution. The amount of piroxicam were quantified using a HPLC system consisting of solvent delivery system. Following adoption of ultrasound 1 MHZ, it showed relatively high permeation rate where it was compared with non treated by ultrasound. The influence of duty cycle having an effect on skin permeation rate was slight higher in the case of using pulsed mode. Skin permeation increase attended by intensity of ultrasound, the permeation of trice was accelerated at 2.0 W/$cm^{2}$ than 1.0 W/$cm^{2}$. The skin permeation of piroxicam was substantially influenced by ultrasound. Anti-inflammatory effects were determined using carrageenan-induced paw swelling method in SD rat. Paw swelling tests showed that pulsed phonophoresis group was more effective than control group and only gel application group. The conclusion of phonophoresis was found to improve significantly the skin permeation in vitro and the anti-inflammatory effect in vivo.