Kinetics of Hydrogen Movement in Zinc

Jeong_Keun Lee 한국물리학회 2007 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.51 No.II

The diffusivity of hydrogen in pure zinc was determined by using hydrogen extraction with cylindrical specimens of 1 cm in diameter and 1 cm in length. The measured values of the diffusivity did not vary statistically with the purity of the zinc, which indicates that the grain boundary did not play an important role in the hydrogen evolution from zinc. The values of the diffusivity obtained in the temperature range from 50 to 300 $^\circ$C showed that the diffusivity depended exponentially on the temperature. The repeatability of the hydrogen extraction method at low temperatures was better than that at high temperatures. A combination of the measured value of the frequency factor, $D_0$, with Zenner's theoretical expression of $D_0$ for interstitial diffusion yielded a negative value of the activation entropy, $\Delta S$, which was explained by the hypothesis that the change in the vibrational frequency of hydrogen particles that jumped between adjacent sites contributed more to $\Delta S$ than the zinc lattice distortion caused by the movement of hydrogen particles did.

정상인에서 부분적 수면박탈이 수면구조에 미치는 영향

왕성근,이정규,이충숙,최하석,유남재,정인형,이선우 충남대학교 의과대학 지역사회의학연구소 1992 충남의대잡지 Vol.19 No.2

To identify the effects of partial sleep deprivation on the sleep structure, the authors performed polysomnographic study for 9 healthy young adults. The subjects were college students, ranging in age from 20 to 25 years, without personal past or present histories of medical, neurological, or psychiatric illness and suffering from current sleep disturbance or parasomomnias. Sleep records were analyzed according to the criteria of Rechtschaffen and Kales' manual and tried paired t-test. The results were summarized as follows. 1. As for sleep parameters, total sleep time(TST), REM latency and REM duration were not changed significantly during deprivation period and recovery period compared with baseline. Sleep efficiency increased significantly during deprivation period and recovery period compaired with baseline, and sleep latency and WASO were shortened significantly during deprivation period and recovery period compared with baseline. 2. As for sleep structure, 1) The absolute value(minutes) of stage 1 decreased significantly during deprivation period and first recovery night compared with baseline, and the relative value(percentage) of stage 1 decreased significantly during deprivation period and recovery period compared with baseline. 2) The absolute value(minutes) of stage 2 decreased significantly during deprivation period compared with baseline, and the relative value(percentage) of stage 2 decreased significantly during deprivation period and first recovery night compared with baseline. 3) The absolute value(minutes) of slow wave sleep were not changed significantly during deprivation period and recovery period compared with baseline, and the relative value(percentage) of slow wave sleep increased significantly during recovery period compared with baseline. 4) The absolute value(minutes) of REM sleep decreased significantly during deprivation period compared with baseline, and the relative value(percentage) of REM sleep decreased significantly in the first deprivation night but, were not changed significantly during recovery period compared with baseline.

추황배(Pyrus pyrifolia Nakai cv. Chuhwangbae) 과피로부터 1종의 Sterol과 3종의 배당체 화합물의 단리·동정

이유건(Yu Geon Lee1),조정용(Jeong-Yong Cho),이현주(Hyun Joo Lee),이용현(Yong Hyun Lee),이상현(Sang-Hyun Lee),한태호(Tae-Ho Han),김월수(Wol-Soo Kim),박근형(Keun-Hyung Park),문제학(Jae-Hak Moon) 한국식품과학회 2013 한국식품과학회지 Vol.45 No.5

본 연구에서는 배의 유용성 증명을 위한 일환으로 배의 화학성분을 분자수준에서 밝히고자 하였다. 이에 배 과피 MeOH 추출물을 용매분획하여 얻은 EtOAc-산성 분획과 EtOAc-중성분획을 대상으로 Sephadex LH-20, silica gel, 그리고 ODS colmn chromatography와 HPLC를 이용하여 정제 및 단리하였다. 그 결과, EtOAc-산성 분획과 EtOAc-중성 분획으로부터 각각 2종씩의 화합물을 단리하였다. 단리된 화합물 1-4는 1H- 및 13C-NMR 분석을 통하여 각각 (S)-(+)-2-cis-abscisic acid O-β-D-glucopyranosyl ester (화합물 1), 1-[4-O-β-D-glucopyranosyl]phenyl ethanone(piceoside, 화합물 2), β-sitosterol (화합물 3), 그리고 β-sitosteryl 3-O-β-D-glucopyranoside (화합물 4)로 동정되었다. 단리된 3종의 배당체 화합물(화합물 1, 2, 4)들은 본 연구에 의해 배로부터 처음 동정되었으며, 화합물 3은 추황배로부터 처음 동정되었다. 본 연구결과가 배 함유 성분연구는 물론 배의 기능성 해명 연구에도 추후 중요한 기초자료로 활용되길 기대한다. We isolated and identified antioxidants from acidic and neutral ethyl acetate fractions of the peel of pear (Pyrus pyrifolia N. cv. Chuhwangbae). We isolated 4 compounds from the methanol extract, by using 3 different types of column chromatography (Sephadex LH-20, silica gel, and octadecylsilane) and preparative HPLC. We identified the isolated compounds as (S)-(+)-2-cis-abscisic acid O-β-D-glucopyranosyl ester (compound 1), 1-[4-O-β-D-glucopyranosyl]phenyl ethanone (picroside, compound 2), β-sitosterol (compound 3), and β-sitosteryl 3-O-β-D-glucopyranoside (compound 4) by nuclear magnetic resonance analysis. We are the first to report the identification of compounds 1, 2, and 4 from pear.

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

급성 충수돌기염 의증 환자의 진단에서 컴퓨터 단층촬영과 초음파검사의 비교 분석

이정훈,최필조,심민섭,송근정,정연권 대한응급의학회 2001 대한응급의학회지 Vol.12 No.3

Background: This study was conducted to compare the accuracy of computered tomography(CT) and sonography(US) in diagnosing acute appendicitis and to analyze the radiologic factors which influence the result. Methods: We retrospectively studied the cases of 53 patients who were suspected of having appendicitis and who were examined by CT and US covered a three-year period. The final diagnosis was determined from the surgico-pathologic diagnosis and clinical follow-up for two months, as well as from the discharge diagnosis. Results: Thirty-eight(38) patients had acute appendicitis; 15 patients did not. In the analysis, CT and US, respectively, revealed sensitivities of 89.5% and 73.7%, specificities of 93.3% and 60.0%, positive predictive values of 97.1% and 82.4%, negative predictive values of 77.8% and 47.4%. Among patients diagnosed with acute appendicitis, 10 patients were discordant in the US and the CT examinations; CT findings were correct in 8 and US findings in 2. Among non-appendicitis patients, 5 patients were discordant in the US and the CT examinations; CT was correct in 5 and US in 0. Nighteen(19) patients had complications such as an abscess or a perforation. Among these patients, the degree and the extent of the complication were accurately evaluated by CT in 15 patients and by US in 5 patients. Conclusion: CT is more accurate than US in diagnosing and excluding acute appendicitis. The use of CT will substantially decrease unnecessary laparotomies and post-operation complications.

Amphotericin B의 投與가 마우스의 免疫反應에 미치는 影響

李正鎬,黃翼根 全北大學校 1983 論文集 Vol.25 No.-

Amphotericin B(AmB)가 免疫反應에 關與하는 機轉을 究明하기 爲한 基礎資料를 얻고자 마우스를 모델로 抗原(SRBC)의 感作量, AmB의 投與時期 및 投與量에 따라 AmB가 細胞性免疫反應에 미치는 效果를 足蹠腫腸反應檢査 및 脾臟細胞의 로젵 形成能儉査로 測定하였던 바 다음과 같은 結果를 얻었다. 抗原感作(10^8SRBC/mouse)과 同時에 여러 濃度의 AmB를 投與한 後 發顯되는 DTH는 AmB를 350㎍Υ mouse의 濃度로 投與한 群에서 가장 顯著한 增加를 보였다. 여러 濃度의 感作抗原下에서의 Arthus反應이나 DTH는 모두 投原量에 關係없이 AmB(350㎍/mouse)를 投與한 群에서 對照이 比하여 大體로 增加되었으며, 對照群에서의 最適感作抗原量은 10^7SRBC/mouse이었으나, AmB를 投與한 群에서는 10^8SRBC/mouse이었다. AmB(350㎍/mouse)의 投與時期에 따른 感作抗原(10^8SRBC/mouse)에 對한 DTH는 AmB를 感作 後投與한 群에서는 對照에 比하여 差異ffm 보이지 않았으나 AmB를 抗原感作 前 또는 感作과 同時에 投與한 群에서는 對照에 比하여 DTH가 增加되었는데 特히 AmB를 抗原感作과 同時에 投與한 群에서 그 報加가 가장 顯著하였다. AmB(350㎍/mouse)의 投與時期에 따른 感作마우스(10^8SRBC/mouse)의 로젵 形成率AmB를 抗原 感作前에 投與한 群에서는 對照에 比하여 오히려 減少되었으나, AmB를 抗原感作과 同時 또는 感作 後에 投與한 群에서는 對照에 比하여 增加되었는데 特히 抗原感作 後 4日에 AmB를 投與한 群에서 그 增加가 가장 顯著하였다. 以上의 結果로 AmB가 免疫反應을 增强시키는 最適感作抗原濃度, AmB의 最適投與量 및 投與時期 等을 밝힐 수 있었으며, AmB가 免疫反應에 關與하는 몇가지 可能性있는 機轉을 類推할 수 있었다. Amphotericin B (AmB), a polyene antibiotic that binds to choresterol in the plasma membrane of eukaryotic cells, is clinically used in the treatment of systemic fungal infection. Using in vitro and in vivo models, several investigators have demonstrated both immunostimulatory and immunosuppressive effect of AmB. The immunostimulatory effect of AmB may be a useful adjunct to host defenses against fungi, while the immunosuppressive activity may have deleterious effects. But there has still been no report to evaluate the effects of AmB on delayed hypersensitivity (DTH) and rosette forming cell reaction (RFR). Therefore, this present study was attempted to investigate the immunomodulating effect of AmB on the reponses to sheep erythrocytes(SRBC) by footpad swelling reaction and rosette formation of spleen cells in ICR mice. DTH in AmB-treated mice (17.5㎎/㎏ per mouse) were generally increased compared to those of PBS-treated controls. The optimal immunopotentiating effect of AmB was provoked when the mouse was sensiitzed with SRBC at 10-fold higher doses of antigen (10^8SRBC/mouse) than those required for optimal immune response in PBS-treated control mice (10^7SRBC/mouse). DTH of AmB-treated mice were enhanced when AmB was injected into mice before or at the same time of SRBC-sensitization, particularly the enhancement degree of DTH was more prominent when mice were treated with AmB at the same time of sensitization than before. However, there was no significant difference in the response when AmB given after sensitization. The percentage of RFR was decreased compared with those of control when AmB was administrated before SRBC-sensitization, but was increased when AmB was treated after SRBC.

기성 콘크리트 파일 두부정리를 위한 자동화 장비의 개발

이정호,김정렬,김영석,조문영,김성근 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2

During the last few years, the use of prefabricated concrete pile has been gradually increased in many construction sites. Cutting work of the concrete pile is an important task to crush a part of pile head which is compressed with more than 800㎏/㎠, It is usually performed by a crusher and three to four skilled workers. Recent analysis results of the pile cutting work reveal that it frequently makes a lot of cracks which significantly reduce the strength of the pile and is labor-intensive work. The primary objective of this study is to propose conceptual designs for developing an automated pile cutting machine. It is anticipated that the development of the automated pile cutting machine would be able to bring improvements in safety, productivity, quality as well as cost saving.

편측성 완전 구순구개열 환자의 포괄적 치료

이정근,황병남,최은주,김용빈 대한악안면성형재건외과학회 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.4

Cleft lip and palate is one of the congenital anomalies which need comprehensive and multidisciplinary treatment plan because 1) oral cavity is an important organ with masticatory function as a start of digestive tract, 2) anatomic symmetry and balance is esthetically important in midfacial area, and 3) it is also important to prevent psycho-social problems by adequate restoration of normal facial appearance. There are many different protocols in the treatment of cleft lip and palate, but our department has adopted and modified the Z□rich protocol, as published in the Journal of Korean Cleft Lip and Palate Association in 1998. The first challenge is feeding. Type of feeding aid ranges from simple obturators to active orthopedic appliances. In our department we use passive-type plate made up of soft and hard acrylic resin which permits normal maxillary growth. We use Millard's method to restore normal appearance and function of unilateral complete cleft lip. In consideration of both maxillary growth and phonetic problems, we first close soft palate at 18 months of age and delay the hard palate palatoplasty until 4 to 5 years of age. When soft palate is closed, posterior third of the hard palate is intentionally not denuded to allow normal maxillary growth. In hard palate palatoplasty the mucoperiosteum of affected site is not mobilized to permit residual growth of the maxilla. We have treated a patient with unilateral complete cleft lip and palate by Ajou protocol, which is a kind of modified Z□rich protocol. It is as follows: Infantile orthopedics with passive-type plate such as Hotz plate, cheiloplasty with Millard's rotation-advancement flap, and two stage palatoplasty. It is followed by orthodontic treatment and secondary osteoplasty to augment cleft alveolus, orthognathic surgery, and finally rehabilitation with conventional prosthodontic treatment or implant installation. The result was good up to now, but we are later to investigate the final result with longitudinal follow-up study according to master plan by Ajou protocol.

골뱅이(Buccinum Undatum) 알레르기 : 감작률과 다른 음식물 항원과의 연관성 Sensitization rate and its relationship with other food allergens

이재영,윤성호,서유진,최정희,서창희,남동호,김윤근,민경업,박해심 대한천식 및 알레르기학회 2004 천식 및 알레르기 Vol.24 No.1

Background : The common whelk (Buccinum undatum) is one of the largest and most common snails in the North Atlantic. In Korea and Japan, common whelk is a popular eatable shellfish. Although shellfish has been known as the one of the most common causes of food allergy, there has been no published report on allergenecity and clinical significance of this sea snail. In this study, we determined the sensitization rate to common whelk and its relationship with other food allergens in allergy patients. Method : We carried out the skin prick test (SPT) with commonly consumed food stuffs in Korea including common whelk in 1700 patients over 1 year. The specific IgE to common whelk were detected by enzyme-linked immunosorbent assay (ELISA). ELISA inhibition test using sensitized sera was conducted. Results : SPT to common whelk was positive (≥2+) in 83 (4.9%) patients studied. Twenty-four (38.7%) of 62 SPT-positive patients had high serum specific IgE to common whelk. ELISA inhibition test showed significant inhibitions by abalone as well as by common whelk and, minimal inhibition were noted by shrimp. Significant correlation was also noted in specific IgE levels between common whelk and abalone (r=0.58, F<.05). Conclusion : IgE-sensitization rate to common whelk was 4.9% in allergy patients. Further stuides are needed to evaluate the clinical significance of sensitized patients to common whelk, and to confirm a cross reactivity with abalone. (J Asthma Allergy Immunol 24 : 77-84, 2004)

지방이식의 다양한 임상적 이용

이근철,정영하,김정태,김석권 대한미용성형외과학회 1997 Archives of Aesthetic Plastic Surgery Vol.3 No.1

Generally alloplastic matrials such as collagen compound and liquid silicone injection. or autologous fat injection have been used for correction of surface irregularity. But, except for autologous fat injection, the other methods have been proved to be not effective or even dangerous. Then with the explosion in the popularity of liposuction, the autologous fat injection has been applied to variable clinical uses for contouring of the soft tissue irregularities. The author performed main operations with fat injection as ancillary procedure in 16 patients from 1993 to 1996, and long term follow-ups were reported. The lesions treated most frequently were cheeks, and others were thighs, legs, nasolabial folds and upper eyelids in order of frequency. The donor sites were lower abdomen, thigh, buttock and cheek. Our method of fat injection was used as an ancillary procedure for improving post-operative results in variable cases (craniofacial microsomia, fibrous dysplasia, asymmetry of leg, etc). And the important technical points in our method for reducing the absorption of fat after injection were atraumatic liposuction, multilayered dispersed injection, and 20% overcorrection. We obtained satisfactory aethetic results without major complications.