• 폴리머
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• 제26권3호
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• pp.353-359
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• 2002

본 연구에서는 고강도 초음파를 이용하여 분자량이 다른 poly(ethylene oxide) (PEO)를 증류수에 분산시켜 초음파 가진(加振) 시간이 PEO의 성질에 미치는 영향을 조사하였다. 고강도 초음파는 PEO 수용액 상에서 동공 형성 및 파괴를 일으켜서 PEO 거대 라디칼을 형성하였으며 이로인하여 PEO 자체의 유변학적 성질, 화학 구조 그리고 용융 거동이 현저하게 변화되었다. 초음파 가진에 의하여 PEO의 용융 점도는 감소되었고, 물과 PEO 사슬에서 비롯된 여러 종류의 라디칼들의 상호 작용으로 말미암아 새로운 말단기들이 생성되었다. 아울러 분자량에 따라 상이한 용융 거동을 나타내었는데, 상대적으로 분자량이 큰 경우에는 가진되지 않은 PEO에 비하여 결정화 속도가 느려지고 용융 피크의 강도가 감소되는 특성을 나타내었다.

• 한국산학기술학회논문지
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• 제22권5호
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• pp.221-228
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• 2021

최근 자궁근종에 대한 치료방법으로서 비수술적 고강도 집속 초음파 (High-Intensity Focused Ultrasound, HIFU)한 인식이 증대되고 있다. 본 논문에서는 한국에서 자궁근종의 HIFU 치료에 대한 부인과 의사들의 인식을 평가해 보고자 하였다. 우리는 162명의 한국의 부인과 의사들에게 인구통계학적 특성, 자궁근종에 대한 실제 진료의 패턴, 자궁근종의 HIFU 치료에 대한 의견에 대하여 설문을 시행하여 분석하였다. 162명 중, 2.8 %에서 HIFU를 자궁근종의 1차 치료로 고려하였다. HIFU는 응답자의 19 %에서만 이용가능 하였고, 이중 58 %에서는 HIFU에 대한 의뢰를 경험하였다. 자궁근종 치료로서 HIFU에 대한 인식을 살펴보았을 때, 응답자의 19 %에서만 효과적이라고 답하였다. 가장 흔한 부작용으로 생각되는 것은 자궁육종의 적절한 치료가 늦어지는 것 (59 %) 이었고, 그 다음이 장 손상 (52 %) 이었다. 응답자들이 HIFU를 고려하기에 적합하다고 생각한 경우로는 연령이 40세부터 49세 사이이며, 추후 임신 계획이 없고, 중간 크기 (5-6 cm)의 자궁근종이 2개까지 일 때였다. 자궁근종 치료로서 HIFU에 대한 한국의 부인과 의사들의 인식은 여전히 호의적이지 않으며, 근무하는 병원에서 HIFU를 이용 가능할 때, HIFU에 대한 인식이 좀 더 긍정적인 경향을 보였다. 여러 나라에서 더 많은 수의 부인과 의사들을 대상으로 한 연구뿐만 아니라, HIFU의 장기적인 결과에 대한 추가적인 연구가 더 필요하다.

• IEIE Transactions on Smart Processing and Computing
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• 제3권1호
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• pp.28-34
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• 2014

Recently, ultrasound therapy has become a new and effective treatment for many brain diseases. Therefore, skull-mimicking phantoms have been developed to simulate the skull and brain tissue of a human and allow further research into ultrasound therapy. In this study, the suitability of various skull-mimicking materials(HDPE, POM C, Acrylic) for studies of brain-tumor treatments was evaluated using focused ultrasound. The acoustic properties of three synthetic resins were measured. The skull-mimicking materials were then combined with an egg white phantom to observe the differences in the ultrasound beam distortion according to the type of material. High-intensity polyethylene was found to be suitable as a skull-mimicking phantom because it had acoustic properties and a denatured-area shape that was close to those of the skull,. In this study, a skull-mimicking phantom with a multi-layer structure was produced after evaluating several skull-mimicking materials. This made it possible to predict the denaturation in a skull in relation to focused ultrasound. The development of a therapeutic protocol for a range of brain diseases will be useful in the future.

• Fisheries and Aquatic Sciences
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• 제2권2호
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• pp.149-154
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• 1999

Response Surface Methodology was applied for optimizing the processing parameters of ultrasound treatment in order to produce low-molecular alginate. The use of ultrasound significantly reduced viscosity of alginate solutions. Suggested parameters of ultrasound treatment for maximum reduction of alginate molecular weight were: specific intensity, 115.81 $W/cm^2$ at 20kHz frequency; treatment time, 35.55 min; temperature, $20.08^{\circ}C$; alginate concentration, $2.5\%$. Low-molecular alginate obtained by ultrasound had two peaks on Sepharose CL-6B gel filtration. The viscosities of control, fraction I, and fraction II at $0.1\%$ concentration and $25^{\circ}C$ were 3.07, 1.23, and 0.82cps, respectively. Molecular weights of control, fraction I, and fraction II alginates were 336,500, 70,400, and 52,800 daltons, and their solubilities were 3, 6, and $14\%$, respectively. The lower molecular weight of alginate, the lower the alcohol precipitation and the higher $Ca^{2+}$ ion binding capacities. Heavy metal ion binding capacities of alginates were high in the following order of Pb, Cd, Zn, and Co.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회.한국자기공명학회 2005년도 공동학술대회
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• pp.77-78
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• 2005

A specific FUS-MRI platform was designed for breast cancer treatment. phased array technologies, sideways FUS transmission, and spatio-temporal temperature control in the complete region of interest, were combined for a novel therapy approach with enhanced safety and afficacy. A phase I clinical trial will start soon.

• 한국유변학회:학술대회논문집
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• 한국유변학회 2006년도 춘계 학술발표회 논문집
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• pp.161-164
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• 2006

• 한국유변학회:학술대회논문집
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• 한국유변학회 2003년도 춘계학술발표회 논문집
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• pp.119-122
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• 2003

No Abstract, See Full Text

• 한국유변학회:학술대회논문집
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• 한국유변학회 2002년도 추계학술발표회 논문집
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• pp.143-146
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• 2002

No Abstract, See Full Text

• The Korean Journal of Pain
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• 제26권4호
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• pp.387-391
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• 2013

A 64-year-old woman visited our pain clinic with the pain of right lateral side of thigh for one year. Her pain always started from knee and was radiated to buttock area when symptom was severe. She showed significant tenderness at knee lateral side and local tightness at lateral thigh. Magnetic resonance image of the knee was performed and we could identify high signal intensity of iliotibial band through coronal and axial view. In spite of medication and physical stretching exercise of iliotibial band for one month, she did not show any improvement of pain. To alleviate her symptom, ultrasound guided local corticosteroid injection targeting beneath the iliotibial band was performed. After the procedure, the reduction of pain was significant and there was no need for further management.

• Korea-Australia Rheology Journal
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• 제14권3호
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• pp.121-128
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• 2002

A series of thermoplastic polymers and their blends were melt-processed with high intensity ultrasonic wave in an intensive mixer. For the effective transfer of ultrasonic energy, an experimental apparatus was specially designed so that polymer melt can directly contact with ultrasonic horn. It was observed that significant variations in the rheological properties of polymers occur due to the unique action of ultrasonic wave without any aid of chemical additives. It was also found that the direct sonication on immiscible polymer blends in melt state reduces the domain sizes considerably and stabilizes the phase morphology of the blends. The degree of compatibilization was strongly affected by viscosity ratio of the components and the morphology was stable after annealing in properly compatibilized blends. It is suggested that ultrasound assisted melt mixing can lead to in-situ copolymer formation between the components and consequently provide an effective route to compatibilize immiscible polymer blends.