• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제39권2호
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• pp.94-99
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• 2013

Focal osteoporotic bone marrow defect (FOBMD) is a radiolucent area corresponding to the presence of hematopoietic tissue rarely found in the jaws. FOBMD is most commonly located in the mandibular edentulous posterior area of a middle-aged female. From November 2011 to November 2012, we experienced three cases involving removal of implants that had accidentally fallen into the FOBMD area. All patients happened to be female, with a mean age of 54 years (range: 51-60 years). One case involved hypoesthesia of the lower lip and chin, while two cases healed without any complication. Displacement of an implant into the FOBMD area is an unusual event, which occurs rarely during placement of a dental fixture. The purpose of this study was to report on three cases of FOBMD and to provide a review of related literature.

• BMB Reports
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• 제49권2호
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• pp.71-72
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• 2016

Focal cortical dysplasia type II (FCDII) is a focal malformation of the developing cerebral cortex and the major cause of intractable epilepsy. However, since the molecular genetic etiology of FCD has remained enigmatic, the effective therapeutic target for this condition has remained poorly understood. Our recent study on FCD utilizing various deep sequencing platforms identified somatic mutations in MTOR (existing as low as 1% allelic frequency) only in the affected brain tissues. We observed that these mutations induced hyperactivation of the mTOR kinase. In addition, focal cortical expression of mutant MTOR using in utero electroporation in mice, recapitulated the neuropathological features of FCDII, such as migration defect, cytomegalic neuron and spontaneous seizures. Furthermore, seizures and dysmorphic neurons were rescued by the administration of mTOR inhibitor, rapamycin. This study provides the first evidence that brain somatic activating mutations in MTOR cause FCD, and suggests the potential drug target for intractable epilepsy in FCD patients.

• Journal of Biosystems Engineering
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• 제26권2호
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• pp.169-176
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• 2001

Defect of apple was depreciated the product value and causes storage disease seriously. To detect the defect of ‘Fuji’apple with machine vision system, the optical characteristics of defect should be investigated. In this research, absorbance spectra of defect were acquired by spectrophotometer in the range of visible and NIR region(400∼1,100nm) and L*a*b* color values were also acquired by colorimeter. NIR machine vision system was constructed with B&W camera, frame grabber, 16 tungsten-halogen lamps, variable focal length lens and NIR bandpass filter which was mounted to lens outward. Average gray values of defect at 15 NIR wavelength were acquired and the significant NIR wavelength was selected by comparing Mahalanobis distance between sound and defective apple. As the result of Mahalanobis distance analysis, the significant wavelength to discriminate the defectives in ‘Fuji’apple were found to be 720nm for scab and 970nm for bruise and cuts and 920nm was also effective regardless of defective types.

• 비파괴검사학회지
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• 제31권6호
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• pp.635-641
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• 2011

In ultrasonic testing of dissimilar metal welds, application of phased array technique in terms of incident beam focusing is not easy because of complicated material structures formed during the multi-pass welding process. Time reversal(TR) techniques can overcome some limitations of phased array since they are self-focusing that does not depend on the geometrical and physical properties of testing components. In this paper, we test the possibility of TR focusing on a defect within anisotropic, heterogeneous austenitic welds. A commercial simulation software is employed for TR focusing and imaging of a side-drilled hole. The performance of time reversed adaptive focal law is compared with those of calculated focal laws for both anisotropic and isotropic welds.

• 대한기계학회논문집A
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• 제28권7호
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• pp.1047-1054
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• 2004

Internal defects in the glass, like-as micro-voids, micro-cracks, or inclusions, easily cause the failure when the glass is exposed to the shock or the thermal variation. In order to produce the highly reliable glass product, the precision inspection of the defect in the glass is required. For this purpose, this paper proposes a machine vision technique based on the auto-focusing method, which searches the defect and measures the location under the fact that the edge image of defect must be the most clear when the focal plane of CCD camera is coincided with the defect. As for the search index, the gradient indicator is presented. The basic principles are verified through the simulations for the computer-generated defect images, where the affects of defect shape, gray level of background, and the brightness of the defect image are also analyzed. Finally, experimental results for actual glass specimens are shown to confirm the applicability of this method to the actual field.

• 한국생산제조학회지
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• 제6권2호
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• pp.76-82
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• 1997

The discrimination of flaw shape and sizing is very important subject in the material evaluation for semiconductor and new materials. The aim of this paper is to investigate the spectrum analysis of artificial defect signal captured from steel ball embedded in the resin. The results show that it can be evaluated quantitatively the size of artificial defect, from the amplitude variation of same frequency if the probe with same diameter and focal length is used. Comparing with the amplitude variation of the high frequency component and low frequency component obtained from the distance of defect center position, it can be estimated steel ball and flat bottm defect.

• 비파괴검사학회지
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• 제22권6호
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• pp.637-642
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• 2002

An arc-shaped line array slit has been used for the laser generation of focused Lamb waves. The spatially expanded Nd:YAG pulse laser was illuminated through the arc-shaped line array slit on the surface of a sample plate to generate the Lamb waves of the same pattern as the slit. Then the generated Lamb waves were focused at the focal point of which distance from the slit position is dependent on the curvature of slit arc. The proposed method showed better spatial resolution than the conventional linear array slit in the detection of laser machined linear defect and drill machined circular defect on aluminum plates of 2mm thickness. Using the focused waves, we could detect the linear defect and the circular defect with the improvement of spatial resolution. The method can also be combined with the scanning mechanism to get an image just like by the scanning acoustic microscope(SAM).

• 대한두개안면성형외과학회지
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• 제20권2호
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• pp.139-143
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• 2019

Here we report a case of a focal atypical proliferative nodule (PN) arising from a congenital melanocytic nevus (CMN). Diagnosis was challenging because it had both benign and malignant clinical features. Unusual histopathology, immunohistochemistry, and intraoperative findings of this atypical PN are discussed. A 5-year-old girl was admitted for a congenital $5{\times}5cm$ sized scalp mass. This hemangioma-like soft mass showed biphasic characteristics such as a slow, gradual, and benign increase in size but worrisome dural invasion with cranial bone defect. We removed the scalp mass with clear resection margins. Interoperatively, we found that the cranial bone defect had already filled. Histopathologic examination showed CMN with focal atypical PN. The nodule showed sharp demarcation and cellular pleomorphism. However, in immunohistochemical study, Ki-67 proliferation index and expression levels of protein S-100 and Melan-A were very low. These were unusual findings of atypical PNs. Despite her worrisome preoperative radiologic features, she showed an indolent clinical course compatible with previously reported biologic behavior. The patient underwent follow-up inspection with magnetic resonance imaging every 6 months for up to 3 years. The nodule appeared to be stationary at the last visit.

• 대한골관절종양학회지
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• 제6권2호
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• pp.106-111
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• 2000

국소적 섬유연골성 이형성증(FFCD)은 소아에서 일측성 경골 내반 소견을 보이는 드문 양성 질환이다. FFCD는 근위 경골 내측 골간단과 골간의 이행부에 오목한 방사선 투과 음영 소견을 보이는 전형적인 방사선 소견을 지니고 있다. 경골 내반이 병변 부위에서 발생한다. 내반의 교정과 골결손의 치유가 흔히 자발적으로 일어나기도 하지만 골교정술을 요하기도 한다. 저자들은 절제 조직 생검술로 진단하고 절골술 및 골이식술을 시행함으로써 치유한 FFCD에 의한 일측성 경골 내반 1예를 문헌고찰과 함께 보고하는 바이다.

• Nuclear Medicine and Molecular Imaging
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• 제43권6호
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• pp.519-525
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• 2009

목적: 심근의 F-18 FDG 섭취는 다양한 인자에 의해 영향을 받으며, 가역적인 허혈성 심질환이 있을 경우 심근에서 포도당 대사가 증가된다고 알려졌다. 이 연구에서는 허혈성 심질환의 과거력이 없는 종양 환자에서 시행한 F-18 FDG PET/CT에서 심근 섭취 정도 및 분포를 관찰하고, 심근 관류 SPECT와 비교하여 F-18 FDG 심근 섭취 소견으로 심근 허혈을 예측할 수 있는지를 알아보고자 하였다. 대상 및 방법: 2005년 1월부터 2009년 6월까지 F-18 FDG PET/CT를 시행한 환자 중 3개월 이내에 Tc-99m sestamibi 심근 관류 SPECT를 시행한 환자 77명을 대상으로 후향적 분석을 시행하였다. 결과: 77명의 환자 중 F-18 FDG PET/CT에서 심근에 섭취가 증가하여 있는 경우는 55명(71.4%)이었다. 이 중 40명은 균등 심근 섭취를 보였고 15명은 국소 심근 섭취를 보였다. 균등 F-18 FDG 섭취 증가를 보인 40명의 환자 중 17명(42.5%)에서 격벽에 섭취 감소가 관찰되었으나, 심근 관류 SPECT상 유의한 관류 이상은 관찰되지 않았다. 전체 심근에 균등한 섭취를 보인 23명(57.5%) 중 1명(4.3%)에서 하벽에 가역적인 관류 결손이 관찰되었고, 1명(4.3%)에서 측벽에 비가역적인 관류 결손이 관찰되었으며, 21명(91.3%)에서는 관류 결손이 관찰되지 않았다. 국소 심근 섭취를 보인 15명 중 9명(60.0%)은 기저부에 국소 섭취 증가를 보였고, 이 중 1명에서 심첨측벽에 가역적인 관류 결손이 관찰되었다. 국소적인 심근 섭취를 보인 나머지 6명(40.0%)의 환자 중에서 4명(66.7%)의 환자에서 가역적인 관류 결손이 관찰되었다. 결론: 전신 F-18 PET/CT에서 심근에 격벽 감소나 기저부 증가를 제외한 국소적인 섭취 증가가 관찰되는 경우에는 허혈성 심질환의 가능성이 있으므로 추가적인 진단 검사가 필요하다.