Insulation Coating of Fe–Si–Cr Soft Magnetic Powder by Selective Oxidation

Jae‑Young Park,Kwangsuk Park,Bosung Seo,Julien O. Fadonougbo,Tae‑Wook Na,Ki Beom Park,Hyeon‑Tae Im,Nong‑Moon Hwang,Hyung‑Ki Park 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

This study examines the insulation coating technology of Fe–Si–Cr powder via selective oxidation annealing, which oxidizeselements selectively by controlling the oxidation potential. The study calculated the oxidation driving force of Fe, Si, andCr, and conducted a thermodynamic analysis of oxidation and reduction conditions according to temperature and oxidationpotential. Based on the results, a selective oxidation annealing was performed in an atmosphere in which Fe is reduced andonly Si and Cr are selectively oxidized. The oxidation potential was controlled through the partial pressure ratio of hydrogenand water vapor. The XPS analysis results confirmed that a Si and Cr complex oxide layer formed on the powder surfaceafter the selective oxidation annealing. Afterward, withstanding voltages were analyzed to evaluate the insulation property. Then, the withstanding voltage of the powder applying the selective oxidation annealing increased significantly comparedto that of the initial powder. Further analysis showed that the powder annealed in an air atmosphere had a significantly lowersaturation magnetic flux density than the initial powder, while the powder applying the selective oxidation annealing hadonly a slightly reduced saturation magnetic flux density.

서울의 Penicillinase Producing Neisseria gonorrhoeae 발생빈도(1998)

김재홍,김준호,반재용,이정우,황성주,정준규,정성태,강진문,조흔정,홍창의,정혜신,이한승,김이선,이봉길,이종호,선영우,한기덕,윤성필,이성훈,안종성,박석범,문승현,조항래,김형섭,류지호,황재영,박준홍,손상욱 한양대학교 의과대학 2001 한양의대 학술지 Vol.21 No.1

In recent years, gonorrhea has been pandemic and remains one of the most common STDs in the world, especially in developing countries. For the detection of a more effective therapeutic regimen and assessing the prevalence of Penicillinase Producing Neisseria gonorrhoeae(PPNG), we have been trying to study the patients who have visited the Venereal Disease Clinic of Choong-Ku Public Health Center in Seoul since 1980 by menas of the chromogenic cephalosporin method. In 1998, 93 strians of N. genorrhoeae were isolated, among which 60(64.5%) were PPNG. The prevalence of PPNG in Seoul, which had been decreased to 39% in 1996 after a peak of 74.3% in 1993, is increased to 64.5% in 1998.

흰쥐 시상에서 Epidermal growth factor receptor면역반응 신경세포의 생후 발달에 관한 연구

박영란,정윤영,김종중,문정석,오재욱,정영욱,김주수 조선대학교 2003 The Medical Journal of Chosun University Vol.28 No.1

Background and Objectives : Epidermal growth factor receptor (EGFR), a 170-kDa transmembrane glycoprotein, appears to mediate epidermal growth factor (EGF) activity. Transforming growth factor-α and EGF produce their biological effects in numerous systems by stimulating the EGFR In this study, we examine the postnatal development of EGFR immunoreactivity in the different regions of the thalamus of the rat Materials and Methods : The present study is based on 28 postnatal cases of rat thalamus ranging from the day of birth, postnatal day 0 (P0) to 30 days (P3, P5, P10, P15, P20, P30), and these cases were compared with adult rat thalamus. Cryostat sections were processed free-floating with monoclonal antibody by immunohistochemistry Results : EGFR immunoreactivity in the thalamus of the rat showed very different patterns according to postnatal ages and thalamic areas. EGFR-immunoreactive cells appeared in the first two postnatal weeks, except the ventral posterior thalamic nuclei. In the early postnatal days, EGFR-immunoreactive cells appeared thalamic midline structures, increased progressively in the first two postnatal weeks, and followed mediolateral gradient. The mature patterns of EGFR-immunoreactive cells were achieved at P20 Conclusion : These data indicate that the maturation of EGFR-immunoreactive cells requires a relatively prolonged period of time to achieve an adult configuration. Many growth factors probably play protective or neurotrophic roles at EGFR-immunoreactive neurons of thalamus both young and adult rats In addition to difference in time of appearance in thalamic nuclei and developing pattern with mediolateral gradient suggest that EGFR-immunoreactivities are correlated with the appearance of the related functional.

간세포암과 감별이 어려웠던 악성중피종 치험 1예

김선문,허원석,채경훈,강윤세,정재훈,김연수,박기오,문희석,이엄석,김석현,성재규,이병석,이헌영,신경숙,조준식,송인상,강대영 충남대학교 의학연구소 2003 충남의대잡지 Vol.30 No.2

Malignant peritoneal mesothelioma is a rare neoplasm that arises from the mesothelium of a serosal cavity and is a rapidly fatal disease with a median survival of 4 to 12 months for untreated cases. Recently, we experienced a case with malignant peritoneal mesothelioma who was suspected hepatocelluar carcioma by abdominal CT scan and was confirmed by biopsy including immunohistochemical stain(calretinin) after surgery. We performed tumor excisions and wedge resection of the liver(segment Ⅷ)and inserted Tencoff catheter in abdominal cavity at 25th day of post-operation. We treated with intraperitoneal paclitaxel(25mg/m^(2)/day for 5 days) six courses monthly. She was well tolerable and is still living without any evidence of recurrence for 14th month of post-operation.

제1형 당뇨병 환자에서 췌도세포 동종이식의 반복시행

양태영,정인경,서인아,오은영,조건영,오승훈,김성주,정재훈,민용기,이명식,이문규,김광원,도영수,주성욱 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.24 No.4

연구배경:췌도세포 이식은 시술이 간편하고 안전하기 때문에 반복이식이 가능하여 그 동안 여러 센터에서 반복이식의 성공을 보고한 바 있다. 국내에서도 본 병원을 비롯하여 몇몇 센터에서 췌도세포 이식이 활발히 시도되고 있으나 사람에서의 동종이식 및 동종 이식의 반복시행은 보고된 바 없는 실정이다. 저자 등은 국내 최초로 췌도세포 동종이식을 시행하여, 혈청 C­펩타이드가 증가하고 인슐린 요구량이 감소하였으며, 혈당농도와 당화혈색소의 안정을 보였다. 그러나 이식 70일 후 다시 인슐린 요구량이 증가하고 C­펩타이드가 감소하여 췌도세포 이식을 다시 시행한 바 있다. 2차 이식 후 70여일이 지난 현재 다시 혈청 C­펩타이드가 증가하고, 인슐린 요구량이 더 감소되어 췌도세포 이식에서 반복 시행의 유용성을 보고하는 바이다. 방법:환자는 32세 남자로 17년전 당뇨병 진단 후 인슐린 치료 중이었으며, 3년전 부터는 만성신부전증으로 혈액툭석을 하고있었다. 1999년 12월 25일 신장이식을 하였고 3일 후 췌도이식을 하였으며, 두번째 이식은 70일 후 시행하였다. 췌도분리는 변형된 Recordi방법과 비연속성 자당 농도차(discontinuous density gradient)를 이용하였으며 분리한 췌도는 배양 후 환자의 신장기능이 정상화되고 미생물학 검사에서 음성을 확인한 후 경피경간으로 간문맥을 접근하여 16G 폴리 에틸렌 카테터를 이용하여 간실질에 이식하였다. 결과:1차 췌도이식시 순수분리전 췌도수는 210,000개, 순수분리후 획득한 췌도수는 90,000개, 순도 95%, 세포양 1.0mL 이었고, 2차 췌도이식시 순수분리전 췌도수는 420,000개, 순수분리후 획득한 췌도수는 370,000개, 순도 95%, 세포양 1.5mL 이었다. 1,2차 모두 간문맥을 통해 약 20분에 걸쳐 간실질에 주입하였다. 췌도이식전 인슐린요구량은 75∼75U/일, HbA1e 8∼10%, C­펩타이드 0.6ng/mL 였으며, 1차 췌도이식수 7일째 인슐린 요구량은 40U/일, C­펩타이드 1.5ng/mL, FPS 109mg/mL 였고, 40일 추적관찰 후 인슐린 요구량이 36U/일, C­펩타이드 1.8ng/mL, HbA1e 6.5∼7.0%로 안정되었다. 그러나 이식 50일째부터 인슐린 요구량이 50∼56U/일, C­펩타이드 0.6ng/mL, FPS 130∼200mg/dL로 혈당 조절이 불안정하여 다시 췌도이식을 시행하였다. 2차 이식후 50일이 경과한 현재, 인슐린 요구량은 26U/일, C­펩타이드 1.8ng/mL, FPS 90∼120mg/dL로 다시 안정되었다. 결론:췌도이식은 반복이식이 가능하며, 본 환자의 경우 인슐린요구량 감소, 혈당의 안정화 및 C­펩타이드가 상승하여 이식한 췌도의 기능을 확인할 수 있었고, 향후 스테로이드 등 면역억제가 유지 용량으로 감량되면 인슐린 요구량은 더 감소될 것으로 기대된다. Over the past 20 years, significant advances have been made in human islet transplantation. However, cases of prolonged insulin independence after islet allotransplantation have rarely been reported and over time, a slight, gradual decrease in insulin secretion appears to occur, as suggested by the lower C-peptide. Although preliminary clinical success achieved over the past few years has been considerably higher with whole pancreatic transplant than with isolated islet grafts, both approaches remain experimental. Islet grafts might gain, over time, increasing credibility and might eventually provide an easier alternative in terms of grafting procedures and patient management, as compared with the more "traumatizing" whole-pancreas transplantation. Also, using islet, re-transplantation is possible. But it is not known whether re-transplantation of islet could be suitable for those patients who lost grafted islet function. The aim of the present study was to investigate the benefits of re-transplantation of islet in previously simultaneous islets-kidney transplant (SIK) patient who have lost graft function. Methods : The recipient was a 32 year old male. First islet transplantation was underwent at December 25, 1999. However, the grafted islets lost function after 70 days. So we performed re-transplantation of islets. The isolation of islet was conducted sterilely on a laminarflow hood and isolated by a modified Recordimethod. The islet was injected slowly into the liver via a cannular placed in the potalvein for 20 minutes. Results : Transplanted islets were 90,000 IEq at first islet transplantation, 370,000 IEq at second islet transplantation. The insulin requirement was reduced from 75-85 to 35-40 U/day, the basal C-peptide level was 1.5 ng/mL at 7 days posttransplant Unfortunately, the grafted islets lost function after 70 days. After second transplantation, the insulin requirement was reduced to 26 U/day. Conclusions : Despite the continuous need for exogenous insulin therapy, islet transplantation can prevent wide glucose fluctuations, thus resulting in normalization of glycemic control and improvement in HbAlc, and also, show that islets can be successfully and safely re-transplanted intraportally in patients who have lost previously grafted islet function (J Kor Diabetes Asso 457~466, 2000).

야뇨증 환아들의 심리사회적 특성에 대한 다기관 연구 : 행동 및 정서 문제를 중심으로

조수철,김재원,신민섭,황준원,한상원,박관현,이상돈,김경도,김건석,서홍진,이유식,정재용,김영균,문두건,남궁미경,한창희,조원열,김영식,배기수,이종국,정우영,신의진 大韓神經精神醫學會 2005 신경정신의학 Vol.44 No.6

Objectives : The aim of this study was to examine the behavioral and emotional problems associated with nocturnal enuresis in Korean children. Methods : Three hundred eighteen children with nocturnal enuresis, together with their parents, completed the Child Behavior Checklist (CBCL), Disruptive Behavior Disorder Scale according to DSM-IV (DBDS), Children's Depression Inventory (CDI), State-Trait Anxiety Inventory for Children (STAIC), and Piers-Harris Children's Self-Concept Scale (PHCSC). Ninety-three normal students were selected as the control group. Results : Compared to the normal control group, the mean scores with regard to the withdrawn, social problems, attention problems, delinquent behavior, aggressive behavior, externalizing problems and total problems profiles were significantly higher in the nocturnal enuresis group according to the CBCL results. The nocturnal enuresis group also scored significantly higher in the ADHD and ODD profiles of the DBDS. The nocturnal enuresis group was more depressed and anxious than the control group according to the results of the CDI and STAI. The mean score of the PHCSC was significantly lower in the nocturnal enuresis group when compared to the normal control group. Conclusion : The results of this study suggest that children with nocturnal enuresis in Korea have clinically relevant behavioral and emotional problems. The findings support the link between nocturnal enuresis and psychopathology in Korean children.

지난 2년간의 학회지 "신경정신의학" 심사 평가보고

김찬형,김세주,김도관,김성곤,박원명,송동호,박용천,이영문,오강섭,정영철,이상열,김주한,이동영,이헌정,함병주,김율리,김문두,김정진,이강욱,천근아,김재진,홍진표,홍승철 大韓神經精神醫學會 2007 신경정신의학 Vol.46 No.6

봉선화 뿌리의 成分硏究

文永熙,高在鍾 조선대학교 약학연구소 1994 藥學硏究誌 Vol.16 No.1

Impatiens balsamina Linne(Balsaminaceae)known as "BONG SUN HWA" in Korea and used for treatment of Scrofulosis, Carbunculus and Dysenteria, etc.. From the roots of Impatiens balsamina, α-spinasterol and scopoletin were isolated and characterized by UV, IR, NMR, MS and chemical tests.

Bluetooth Ad hoc 망에서 멀티 슬롯 SAR-QT 알고리즘을 고려한 WAP 패킷의 성능 분석

문일영,노재성,조성준 한국항행학회 2002 韓國航行學會論文誌 Vol.6 No.2

본 논문은 Bluetooth환경에서 SAR-QT(Segment And Re-assembly Quick Transfer)알고리즘을 사용하여 WAP (Wireless Application Protocol)성능을 향상시키기 위한 ,WAP패킷의 전송 시간을 분석하였다. 이러한 WAP의 전송 능력을 향상시키기 위한 한 방법으로 SAR-QT의 과정은 WTP (Wireless Transation Protocol)상위 계층에서 내려온 전체 메시지를 분할한 다음, 베이스밴드에서 패킷을 전송하게 된다. 그리고 Bluetooth 패킷 타입중의(Data-Medium rale) 1, DM3, DM5, 에 따른 WAP over Bluetooth의 패킷 전송 시간을 분석하였다. 이 SAR-QT 알고리즘은 멀티 슬롯으로 전송할 경우 L2CAP (Logical Link Control And Adaptation Protocol)베이스밴드 패킷 전송 시간을 감소 시킨다. 결과로부터, WAP over Bluetooth 환경에서 WAP 패킷의 전송 시간을 줄이기 위해서 WP패킷 크기가 증가해야 한다는 점을 알 수 있었다. 또한, 이러한 무선 채널을 고려한, Rician 페이딩 환경에서 WAP over Bluetooth의 적당한 패킷 크기를 구할 수 있었다. In this paper, it is analyzed that WAP pachket transmission time to improve performance of WAP using SAR-QT algorithm in Bluetooth channel. The order for SAR-QT algorithm to improve the transfer capability, it is fragmented in WTP total messages that are coming down from upper layer and then the packets are sent one at time in baseband. And it is studied that transmission time for WAP over Bluetooth according to DMI, DM3 or DM5 packet type using SAR-QT algorithm in Bluetooth piconet environment. This SAR-QT algorithm decreases WAP packet transmission time of L2CAP baseband packets by sending packet that are spanning multiple slots. From the results, in WAP over Bluetooth channels, it is found out that WTP packet size ougth to be increased to decrease transmission time of WAP packet. In addition, considering BER in wireless channel. optimal WTP packet size is achieved for WAP over Bluetooth in a Rician fading environment.

부산시 공장지역·주거지역 하천의 수질특성분석

문종익,임영석,박광현,김석택,성낙창,박출재 동아대학교 환경문제연구소 2000 硏究報告 Vol.23 No.1

This study is carried out to investigate the water quality changes in Busan Metropolitan streams. The results are as follows. In Busan Metropolitan streams, the loading rates of contaminants are greater in industrial waste water streams than domestic waste water streams. Some sampling points show a little high loading in autumn, but this needs more investigation to make clear the causes. The level of organic contaminants(BOD_(5) and COD_(MN)) is found to be low and does not show seasonal variation in domestic waste water streams. But, the level of organic contaminants in industrial waste water streams is relatively high and seems to be seasonally variable, which is affected by other factors. The nutrient materials, such as nitrogen(as T-N, about 20mg/L) and phosphorus(as T-P, about 2.0mg/L), are abundant than Nak Dong River and the general trends of contaminants level are similar to those of organic contaminants.