백서 대퇴골 결손부에 매식된 밀랍지 혈제의 조직반응에 관한 실험적 연구

김장연,엄인웅,정호용 원광대학교 치의학연구소 1993 圓光齒醫學 Vol.3 No.1

This study was to designed to evaluate the reactions of mouse femoral bone to bone wax. In sixteen mice with a strain of LC.R mouse weighed approximately 300 to 3509g 2.0×2.0㎜ sized bone defects were created by drilling. Half of mice were inserted by bone wax and the remainder serving as control without bone wax application. The mice were sacrified 1, 2, 6, 8 weeks after operation and block specimens were prepared for light microscopy examination. The results obtained were as follows. 1) Histologic features of tissue reaction to bone wax were the presence of inflammatory cell infiltration and multinucleated giant cell. 2) Bone wax healing from the created margin were markedly impaired by the application of bone wax. 3) New bone formation was markedly decreased in bone wax application.

DMBA 유도 햄스터 구강암 발생과정에서 Proliferating Cell Nuclear Antigen, Transglutaminase, Glutathione-S-Transferase π 발현에 대한 면역 조직화학적 연구

김장연,이동근 원광대학교 치의학연구소 1997 圓光齒醫學 Vol.7 No.1

The purpose of this study was to evaluate the relationship between proliferation and cell death during oral carcinogenesis. Syrian golden hamsters which were 3 month old and 90-120gm-weight were used in this study. The 9,10-dimethyl-l,2-benzanthracene (DMBA) in a 0.5% solution in mineral oil was painted on the buccal pouch moucosa 3 times per week in the experimental group during 20 weeks. Control group was painted with mineral oil. In each control and experimental group of 6, 8, 10, 12, 14, 16, 18, 20 weeks, specimen were sectioned for immunohistochemical study with anti-Proliferating Cell Nuclear Antigen (PCNA), anti-transglutaminase and Gluthathion S-Transferase (GST)π antibody. Expression and labeling index of PCNA, transglutaminase and GST-π were obtained by counting the positive cells to those antibodies. The following results were obtained. 1. Histopathologically, finding of epithelial dysplasia of the 6 and 8 weeks experimental group and carcinoma in situ in the 12 weeks and squamous cell carcinoma in those of the 14 weeks were seen. 2. PCNA positive cells were mainly mild expressed in the basal cell layer of normal oral mucosa, increased moderately, after 6 weeks. In suprabasal cell layer, control group is negative but retained moderately between 6 weeks and 14 weeks, and decreased after 16 weeks. In spinous cell layer, restricted only between 12 weeks and 16 weeks, other period is mild or negative. 3. PCNA Index of experimental group revealed the increased peak in 6 weeks and 20 weeks than control group, and retained between 12 weeks and 18 weeks. All experimental group expressed higher PCNA Index than control group (P.<0.05). 4. Transglutaminase expression was localized in outer and suprabasal layers on control group, but after 6 weeks, expression site moved spinous & suprabasal cell layers, and after 8 weeks, expression is spreaded to basal cell layer, and this pattern retained to 20 weeks. Transglutaminase expression of experimental group was higher than control group after 8 weeks. 5. The positive staining of detoxifying agent, Glutathione S-Transferase (GST)π n of experimental group was gradually increased from 6weeks. After 10 weeks, all layer of experimental group was seen positive reaction. The strong positive staining in center of tumor and weak positive staining in periphery of tumor were seen at the stage of squamous cell carcinoma in 14 weeks. According to the results, we should suggest that the more increased proliferation of tumor cell, the more increased expression of PCNA, transglutaminase and GST-π as a detoxifying agent during carcinogenesis by induced DMBA were seen.

백서 대퇴골 결손부에 매식된 밀랍지혈제의 조직반응에 관한 실험적 연구

김장연,한경수,엄인웅,정호용,kim, Jang-Yun,Han, Kyung-Su,Um, In-Woong,Chung, Ho-Yong 대한악안면성형재건외과학회 1992 Maxillofacial Plastic Reconstructive Surgery Vol.14 No.3

This study was to designed to evaluate the reactions of mouse femoral bone to bone wax. In sixteen mice with a strain of I. C. R. mouse weighed approximately 300 to 850g 2.0~2.0mm sized bone defects were created by drilling. Half of mice were inserted by bone wax and the remainder serving as control without bone wax application. The mice were sacrificed 1, 2, 6, 8 weeks after operation and block specimens were prepared for light microscopy examination. The results obtained were as follows. 1. Histologic features of tissue reaction to bone wax were the presence of inflammatory cell infiltration and multinucleated giant cell. 2. Bone ear healing from the created margin were markedly impaired by the application of bone wax 3. New bone formation was markedly decreased in bone wax application.

자가 탈회골의 조직반응에 관한 실험적 연구

김장연,김영조,엄인웅,이동근,이재은 大韓顎顔面成形再建外科學會 1993 Maxillofacial Plastic Reconstructive Surgery Vol.15 No.3

Many surgeons are on the point of bone excision and reconstruction of the bone defects by autograft. xenograft, and allograft in the treatment fo begin and malignant tumors of bone. Of all type of bone grafts, we received the autograft as the best ideal bone graft. Of autogenic bone graft, replantation of excised autogenic bone for reconstructiong the bone defects has been the ideal method until now, but early bone healing reponses and tumor cell devitalization after replantation of excised autogenic bone have not been identified for clinical applications. So, to evaluate bone healing response after replantation in rabbit's calvarial bone, we divided the experimental group into three groups. Group 1 is a fresh autogenous bone group. Group 2 is a deep frozen group. Group 3 is freeze-dried demineralized group. Obtained result were as followed: 1. Inflammatory cell infiltration appeared at I week and disappeared at 4 weeks in all experimental group, Especially, severe inflammatory cell infiltration showed in fresh autogenous bone group at 2 weeks, Especially, severe inflammatory cell infitration showed n fresh autogenous bone group at 2 week Group 3 is the least showing group on the point of inflammatory cell infiltration. 2. Osteoblastic activity evenly increased upto 4 weeks and maintained to 6 weeks and decreased after this period, especially osteoblastic activity in group 2 is less than group 1 and group 3. We can't discriminate between osteoblastic activity of group 1 and that of group 3. 3. In new bone formation, group 3 was more active than any other groups at early stage, but there were little differences among three experimental groups at later state. 4. Bone resorption around the grafted bone slightly appeared at 1 week and disappeared at 4 weeks in all experimental groups. We can find the more bone resorption in group 2 at 2 weeks than any other groups. We could suggest, as appears from our results, that freeze-dried deminiralized bone graft is the useful bone graft in the clinical applications of excised autogenic bone.

DMBA 유도 햄스터 구강암 발생과정에서 Proliferating Cell Nuclear Antigen,Transglutaminase,Glutathione-S-Transferase π 발현에 대한 면역 조직화학적 연구

김장연(Jang Yeon Kim),이동근(Dong Keun Lee) 대한구강악안면외과학회 1997 대한구강악안면외과학회지 Vol.23 No.3

The purpose of this study was to evaluate the relationship between proliferation and cell death during oral carcinogenesis. Syrian golden hamsters which were 3 month old and 90-120 gm-weight were used in this study. The 9, 10-dimethyl -1,2-benzanthracene(DMBA) in a 0.5% solution in mineral oil was painted on the buccal pouch mucosa 3 times per week in the experimental group during 20 weeks. Control group was painted with mineral oil. In each control and experimental group of 6, 8, 10, 12, 14, 16, 18, 20 weeks, specimen were sectioned for immunohistochemical study with ant1-Proliferating Cell Nuclear Antigen(PCNA), anti-transglutaminase transglutaminase and GST-π were obtained by counting the positive cells to those antibodies. The following results were obtained. 1. Histopathologically, finding of epithelial dysplasia of the 6 and 8 weeks experimental group and carcinoma in situ in the 12 weeks and squamous cell carcinoma in those of the 14 weeks were seen. 2. PCNA positive cells were mainly mild expressed in the basal cell layer of normal oral mucosa, increased moderately, after 6 weeks. In suprabasal cell layer, control group is negative but retained moderately between 6 weeks and 14 weeks, and decreased after 16 weeks. In spinous cell layer, restricted only between 12 weeks and 16 weeks, other period is mild or negative. 3. PCNA Index of expermental group revealed the increased peak in 6 weeks and 20 weeks than control group, and retained between 12 weeks and 18 weeks. All experimental group expressed higher PCNA Index than control group(P.<0.05). 4. Tranglutaminase expression was localized in outer and suprabasal layers on control group, but after 6 weeks, expression site moved spinous & suprabasal cell layers, and after 8 weeks, expression is spreaded to basal cell layer, and this pattern retained to 20 weeks. Transglutaminase expression of experimental group was higher than control group after 8 weeks. 5. The positive staining of detoxifying agent, Glutathione S-Transferase(GST)π of experimental group was radually increased from 6 weeks. After 10 weeks, all layer of experimental group was seen positive reaction. The strong positive staining in center of tumor and weak positive staining in periphery of tumor were seen at the stage of squamous cell carcimoma in 14 weeks. According to the results, we should suggest that the more increased proliferation of tumor cell, the more increased expression of PCNA, transglutaminase and GST-n as a detoxifying agent during carcinogenesis by induced DMBA were seen.

電力 스펙트럼 減算方式을 이용한 音聲의 音質向上

金長福,元庭淵 弘益大學校 1986 弘大論叢 Vol.18 No.2

In this paper, a speech enhancement system, which improves intelligibility of noisy speech by using power spectrum subtraction method, is discussed. Degraded speech, added by acoustic noise for background noise, processed using microcomputer which interfaced to PCM system. All algorithms were programed as an assembly language that improved the speed. As the result of the wide-band random noise was added, when the S/N ratio of the unprocessed speech was very low, then the intelligibility of the processed speech was not improved. However, processed speech sound distinctly "less noisy" and "higher quality" at relatively high S/N ratios.

Flexible Electronics용 Sn-58Bi 저온 솔더 특성에 미치는 W 나노 입자의 영향

이재연(Jaeyeon Yi),김장백(Jang Beak Kim),라젠드란 스리 하리니(Sri Harini Rajendran),정재필(Jae Pil Jung) 대한용접·접합학회 2021 대한용접학회 특별강연 및 학술발표대회 개요집 Vol.2021 No.11

마이크로/나노 전자 소자의 고성능화, 융/복합화, 미세화가 급격하기 진행됨에 따라 칩과 기기를 하나의 시스템으로 구성하기 위한 패키징 기술은 그 중요성이 더욱 커지고 있다. 칩의 성능을 효과적으로 활용하기 위하여 다양한 패키징 기술이 개발되었고, 그 중에서 특히 칩과 기판 사이를 직접 적합하는 역할을 하는 솔더의 전기적/환경적 요구를 개선하기 위한 많은 연구가 진행되었다. 특히, Sn-58Bi는 가장 대표적으로 사용되는 저온 무연 솔더 소재는 flexible electronics나 wearable electronics 에 적용되고 있지만, 취성이 있어서 휨 변형이나 장기적인 신뢰성이 떨어진다는 단점을 가지고 있다. 본 연구에서는 기존 Sn-58Bi에 W 나노 입자를 첨가하여 금속학적, 기계적 특성을 개선하고자 하였다. 본 연구에서는 Sn-58Bi에 W 나노 입자의 첨가에 따른 젖음성, 퍼짐성, 미세조직, 인장강도, 연성 등의 물성 변화를 분석, 측정하였다. 실험 결과, Sn-58Bi의 microstructure가 미세화되는 경향을 확인하였고, 최적 나노 W 함량에서 Sn-58Bi에 비해, 인장강도 및 연성이 개선되었다. 이를 통해, W 나노 입자의 최적 첨가 결과에 확보에 따라, felxible electronics용 차세대 솔더로서의 적용 가능성을 확인하였다.

이미지 증대 기법을 이용한 노이즈에 강인한 사과 질병 분류

조현종,김장연,김태경 대한전기학회 2022 전기학회논문지 Vol.71 No.9

When the apple disease occurs, accurate and rapid control must be carried out. If appropriate measures are not taken, the spread of the disease and secondary damage such as soil contamination caused by pesticides may occur. In this paper, the apple disease classification system that can classify the type of disease as well as normal from image is proposed. The apple disease classes consists of Marssonina blotch, Fire Blight, Valsa cacker, Alernaria blotch, and Bitter rot. Xception network was used to extract and learn features from image. Google's AutoAugment CIFAR-10 policy is used to increase apple disease data to increase network’s classification performance. Then, in order to increase the reliability of data, the augmented data was selected by model trained only with original data. Gaussian, Salt-and-pepper, Speckle and Poisson noise were added to the test data to show good performance for noisy input data. We compared the performance of the model trained with original data and augmented data selected by threshold value 0.9. As a result, the proposed study showed a performance improvement of up to 6% in F1-Score.

Characterization of the photopolymerization mechanism and kinetics using In-situ Attenuated Total Reflection-Infrared spectroscopy

고재윤,임호연,김장순 한국고분자학회 2013 한국고분자학회 학술대회 연구논문 초록집 Vol.2013 No.10

Recurrent Syncope Episodes and Exercise Intolerance in Hypertrophic Cardiomyopathy Combined with Atrioventricular Conduction Disturbance

김균희,양동헌,김장연,김남균,최원석,배명환,이장훈,박헌식,조용근,채성철 한국심초음파학회 2013 Journal of Cardiovascular Imaging (J Cardiovasc Im Vol.21 No.3

A 30-year-old female patient with known hypertrophic cardiomyopathy (HCMP) was admitted for recurrent syncope episodes. Electrocardiogram (ECG) showed 2 : 1 atrioventricular (AV) block. Stress echocardiography with bicycle showed high grade AV block at high stage of the exercise associated with exercise intolerance and dyspnea. Twenty-four hour ECG monitoring also revealed high grade AV block and 1 episode of non-sustained ventricular tachycardia. Implantable cardioverter/defibrillatorpacemaker (ICD-P) was inserted. After implantation of ICD-P, conduction disturbance and exercise intolerance were improved. AV block is a rare complication HCMP. There are just a few case reports that present symptoms caused by conduction disturbance in HCMP. This case describes repeated syncope episodes and exercise intolerance caused by conduction disturbance during exercise in HCMP patient. For evaluating the cause of syncope in HCMP, stress echocardiography can be helpful to understand the probable mechanism of syncope.