PVDF 압전소자 활용 전기 에너지 수집

"이수헌", "여인권", "정재성", "박종대" 배재대학교 자연과학연구소 2015 自然科學論文集 Vol.26 No.1

PVDF(Polyvinylidene Fluoride)를 사용하여 진동에너지를 전기적 에너지로 수집할 수 있는 소형 발전시스템을 개발하였다. 개발된 시스템은 온도, 진동, 압력 등의 데이터를 수집하고 무선으로 전송하는 센서 네트워크의 전원으로 사용될 수 있다. We have developed a small electrical energy harvesting system using PVDF(Polyvinylidene Fluoride) which can convert vibrational energy into electrical energy. The developed system can be used as a power source for sensor network which acquire data such as temperature, vibration, pressure, etc and transmit data to a data center

정신분열병, 기분장애와 보르나 바이러스

정성훈,원승희,김상헌 대한생물치료정신의학회 1998 생물치료정신의학 Vol.4 No.2

Borna disease virus is a unique neurotropic agent that appears to have a predilection for the limbic area of the brain. In some animal species, it can produce a behavioral syndrome characterized by aggressive and passive phases. These two characteristics has suggested the relationship between schizophrenia, mood disorder and Borna disease virus. Borna disease virus can infect human brain tissue possibly contributing to the pathophysiology of specific human neuropsychiatric disorders. The authors reviewed several articles suggesting an association of Borna disease virus with schizophrenia and mood disorder.

가토에서 경정맥 이식을 이용한 요도결손 재건술

정재호,이상원,설정현,김효헌 大韓成形外科學會 1999 Archives of Plastic Surgery Vol.26 No.5

There are several methods for the reconstruction of partial urethral defect, including split-thickness skin graft, full-thickness skin graft, and preputial flap and free flap. Despite partial success using these methods, most results are unsatisfactory due to frequent complications such as postoperative infection, fistula formation, hair growth and stricture. There have been several pioneering experiments in this field using autogenous vein graft and the results have been controversial. However, the fact that the endothelial lining is replaced by natural urethral epithlium is generally accepted as a positive effect of this method. This experiment was designed to identify the possibility of using vein graft for the reconstruction of partial urethral defect. Two different types of vein graft method were performed in a total of 20 New Zealand White rabbits with partial urethral defect. Firth, for the patch-graft group, a 1×1 cm rectangular vein graft was sutured at a defective area of the same size. Second, for the tubed-graft group, a vein graft segment 1 cm long was replaced at a segmental urethral defect of the same length. Histologic study was performed at three and eight weeks postoperatively in each group. The process of transitional ell epithelial replacement within the grafted vein was uniformly observed in both experimental groups at three weeks postoperatively. At eight weeks postoperatively, the epithelial replacement was almost complete and histologically undistinguishable. In the retrograde urethrogram performed after 8 weeks, the urinary flow in the patch-graft group was normal and showed no stricture, and two of five rabbits in the tubed-graft group showed partial stricture at the graft site. In conclusion, natural urethral epithelium was restored in grafted venous segments irrespective of the type of graft. Partial stricture was observed in 40% of the tubed-graft group while complete reconstruction was possible in the patch-graft group.

귀리 수용성 추출물의 성분과 점도특성

정헌상,강태수,박희정,정익수,이항영 한국산업식품공학회 2004 산업 식품공학 Vol.8 No.1

귀리 단백 다당체의 산업적 활용 가능성을 검토하고자 추출온도(40~60℃), 에탄올 농도(0~20%0 및 pH(5~9) 조건을 조합하여 중심합성계획법에 따라 얻은 귀리 추출물의 이화학적 특성을 분석하였다. 귀리 추출물의 수율은 6.4~17.9% 범위로 추출온도는 증가할수록 에탄올 농도는 감소할수록 증가하였고 중성일 때 보다 알칼리성이나 산성일 때 수율은 증가하는 경향을 보였다. β-glucan 및 단백질 함량은 각각 21.8~38.3% 및 23.8~29.0% 범위였고 추출온도는 낮을수록 에탄올농도는 높을수록 증가하는 경향을 보였으나 pH에 의한 영향은 없는 것으로 나타났다. 귀리 추출물 수용액은 저온 및 고농도일수록 점도가 증가하였으나 일반적으로 낮은 범위였으며, 전단속도에 따라 감소하는 의소성을 나타내었다. 본 연구결과 저농도 에탄올을 용매로 사용하여 귀리 추출물중의 단백 다당체 함량비를 조절할 수 있었고, 그 수용액 또한 식품용으로 적합한 유체 특성을 갖는 것으로 나타나 산업적인 활용가치가 높을 것으로 기대된다. To examine the utilization of the soluble proteoglucan in oats as a nutraceutical ingredient, soluble components were extracted from Oat Bran Concentrate (OBC) by varying the experiment factors such as temperature (40∼60℃), ethyl alcohol concentration (0∼20%), and pH (5∼9), and then analzed gor their compositions and viscosity. The total yield of iat solube extracts ranged between 6.4∼17.9 and the contents of β-glucan, protein, lipid, and ash in oat extracts were 21.4∼38.3%, 23.2∼29.0%, 8.3∼11.8%, and 5.9∼7.9%, respectively. The exreaction yield increased with the extraction temperature, but decreased with the alchohol concentration and pH. The β-glucan and protein contents increased with increasing temperature and decreasing ethaol concentration. However, the pH level did not influenced those contents. The viscosity of 2% oat extract solution ranged between 8.6∼83.1 cp at different share rates, showing the pseudo-plastic flow properties. Results suggested that extraction condition could be controlled the purity of β-glucan and protein and applied commercially to the large-scale process.

성선자극호르몬유리호르몬 길항제인 Antide가 수컷 생쥐의 유해감각예민도에 미치는 영향

박정현,박제민,김명정,이국희,최상헌,장세헌 대한생물치료정신의학회 2001 생물치료정신의학 Vol.7 No.1

To investigate testosterone effect on nociception, tail flick latency(TFL, sec, 50±1℃) was measured before and after administration of antide(a gonadotropin releasing hormone antagonist) in male mice(Institute of Cancer Research, age of 7-8 weeks, weight 30.5-37.5gm). Testosterone replacement effect on TFL was also examined in antide pre-treated male mice. Experiment 1:30 male mice were randomized into 3 groups(N=10 each). Antide 100㎍/kg, 300㎍/kg or same volume(5.7ml/kg) of 0.2% bovine serum albumin was administered intraperitoneally. TFL was measured before and at 3,6, 9, 12 and 24 hours after injection. Experiment 2 : 40 novice male mice were randomized into 2 groups(N=20 each) and both groups were pre-treated with antide 300㎍/kg i.p.6 hours after antide injection, testosterone 1mg/kg or same volume(5.7ml/kg) of sesame oil was administered i.p. TFL was measured before and 6 hours after antide pre-treatment and 30 min after testosterone/vehicle injection. 1) TFL was significantly shortened by antide in dose dependent manner, In control group, baseline TFL(mean±SD) and those measured at 3,6,9,12 and 24 hours after injection were 4.8±0.7, 5.6±0.7, 5.3±0.6, 5.4±0.6 and 4.7±0.6 sec, respectively. In antide 100㎍/kg group, TFLs were 5.2±0.9, 5.1 ±1.1, 4.2±0.9, 4.4±0.8, 5.1±0.8, and 4.7±0.8 sec, respectively. Compared with baseline, significant hyperalgesia appeared 6 and 9 hours after treatment. TFL measured at 6 hours after treatment was significantly shorter than control. In antide 300㎍/kg group, TFLs were 5.6±0.4, 4.5±0.9, 4.3±0.6, 3.9±1.0, 4.6±0.8 and 4.7±0.9 sec. Significant hyperalgesia appeared 3 hours after treatment and continued thereafter. TFLs measured at 3, 6 and 9 hours after treatment were significantly shorter than control, and TFL at 9 hours was significantly shorter than antide 100㎍/kg group. 2) Hyperalgesia induced by antide pre-treatment was recovered by testosterone replacement. In control group. TFL was shortened by antide pre-treartment(baseline : 6.1±1.0 sec ,6 hr after antide : 4.7±1.0 sec) and there was no significant change after vehicle injection(4.6±0.8 sec). In testosterone group, shortening of TFL induced by antide pre-treatment(baseline: 6.2±0.8 sec; 6 hr after antide: 4.6±0.9 sec) disappeared after testosteronen replacement(0.6±0.8sec). From these results, it is suggested that testosterone has a role of maintaining baseline antinociception and acute decrease in testosterone level results in hyperalgesia.

방사선 장해에 대한 백작약의 방호효과

오헌,박혜란,정일윤,김성호,조성기 대한방사선 방어학회 2002 방사선방어학회지 Vol.27 No.3

방사선 생체 손상에 대한 방호 효과를 나타내는 천연물을 검색하기 위한 일환으로 한의학에서 보혈양혈 탕제에 널리 사용되는 백작약 (peaonia japonica)을 열수총추출물, 에탄올분획, 조다당분획으로 나누어 방사선에 의한 산환적 손상 경감 효과를 검정하였다. 사람 림프구에서 단세포전기영동 (single-cell gel electrophoresis; comet assay)을 수행하여 DNA 손상 경감정도를 관찰하였으며, 마우스에 백작약 추출물을 투여한 다음 8 Gy의 감마선을 조사한 후 간에서 지질과산화 정도를 살펴보았다. 에탄올분획 처리군에서 높은 DNA 손상 경감효과를 확인할 수 있었으며, 지질과산화 억제작용 및 라디칼 소거효과 또한 에탄올분획이 높은 효과를 나타내어 에탄올분획이 방사선 방호에 주된 역할을 하는 것으로 사료된다. 이상의 결과로 보아 백작약은 방사선의 산화적 손상에 대하여 효과적으로 세포 DNA를 방호하고, 생체막의 주성분인 지질의 과산화를 억제하는 것으로 관찰되어 특히, 독성이 거의 없는 천연물이라는 관점에서 방사선 방호제로 적용이 가능할 것으로 사료된다. We investigated the effect of Paeonia japonica (PJ) on radiation-induced oxidative damage to macromolecules in vitro and in vivo. The PJ reduced the tail moment (TM), which was a marker of DNA strand break in single-cell gel electrophoresis (SCGE; comet assay) in the human peripheral blood lymphocytes. Lipid peroxidation in the liver of the ICR mouse, measured as malondiadehyde (MDA), was also reduced by PJ administration. Ethanol fraction of PJ was more effective than polysaccharide fraction of that on reduction of TM in SCGE and lipid peroxidation. Also, Their activities to scavenge DPPH radicals and hydroxyl radicals were observed in vitro, and the activities were due to its ethanol fraction. It is plausible that scavenging of free radicals by PJ extract may have played an important role in providing the protection against the radiation-induced damage. These results indicated that Paeonia japonica might be a useful radioprotector, especially since it is a relatively nontoxic natural product.

수정진동자를 이용한 박막의 상거동 분석

장상목,김종민,이현우,정재헌 동아대학교 공과대학부설 생산기술연구소 1996 生産技術硏究所硏究論文集 Vol.1 No.2

This paper shows that an AT-cut quartz crystal analyzer(Q.C.A) can be applied to the investigation of the microheological change of the polymer blend solution during solvent evaporation process casting blend on the surface of quartz crystal. he blend is made from various compositions of poly(methyl methacrylate) (PMMA) and poly(vinyl acetate)(PVAc), and ethyl acetate as slovent. The resonant frequency and resonant admittance of the blend casting Q.C.A are measured simultaneously and the microheological behavior of the blend is analyzed during ethyl acetate evaporation. The PMMA/PVAc blend solution behaves several informative changes of resonant frequency and resonant admittance during ethyl acetate evaporation, depending on the evaporation time and the blend ratio. The PMMA/PVAc blend solution in ethyl acetate exhibited critical changes of resonant frequency and resonant admittance depending on the evaporation time and blend ratio. From this study, it is known that the quartz crystal analyzer can be successfully applicable to analyze viscoelastic changes on the microrheology and phase separation at the initial stage of the blends of PMMA and PVAc during the solvent, ethyl acetate evaporation process by maesuring the resonant freaquency and the resonant resistance in situ.

복지근피판 거상후 공여부의 재건술

윤정섭,이상헌,신극선,이훈범 대한성형외과학회 1992 Archives of Plastic Surgery Vol.19 No.3

Post radical mastectomy reconstruction using a transverse rectus abdominis myocutaneous flap involves certain problems at the donor site as the difficulty in closure secondary to excessive tension and the development of a postsurgical abdominal hernia. The usage of alloplastic materials such as Marlex may also cause eventual weakness as well as a foreign body reaction. While autogenous tissues may be used for a remote myocutaneous flap transposition or a free-tissue transfer, the problems such as a donor site defect, atrophy secondary to denervation, etc. exist. To avert these problems, we propose to use the autogenous tissue in a manner that provides a dynamic support in addition to the functional reconstruction. The components separation method decribed here separates the muscle groups of the abdominal wall, and allows several advantages over treating the abdominal wall as a single unit. One of the advantages is the increased mobility of individual muscles. The allows transferance of the flap over a greater distance which in turn reduces excessive tension and makes closure of the donor site defect easier. Thus, this procedure provides a dynamic support and reduces the incidence of hernia. We experienced 3 cases of abdominal wall reconstruction after TRAM flap transfer(one case after bilateral TRAM flap, two cases after contralateral unilateral TRAM flap) using external oblique muscle sharing or rectus sharing. So we present clinical cases of the abdominal wall reconstruction after TRAM flap transfer with a review of the literature.

보존적 치료로 회복된 망경색에 의한 급성복증 1예

김정념,이숭환,김정식,김진호,배윤오,박성규,윤상정,한현영,이헌영 충남대학교 의과대학 의학연구소 2003 충남의대잡지 Vol.30 No.1

Omental infarction, the end result of impaired perfusion to the greater omentum, is a rare benign self-limiting clinical entity. The main clinical symptom is non-specific localized abdominal pain with a moderately raised white blood cell and erythrocyte sedimentation rate. These findings often mimic an abdominal surgical emergency. This condition is often misdiagnosed as acute appendicitis or cholecystitis. The characteristic feature of CT scan and ultrasonography provide non-invasive diagnosis in most patients with omental infarction. We report a case of patient whose CT scan showed the characteristic finding of omental infarction. The patient was improved spontaneously only with conservative care.

김천대학 사회교육 활성화 방안에 관한 연구

고정환 ; 윤옥현 ; 박홍기 ; 전기환 ; 김상민 ; 김학민 ; 박희룡 김천대학교 1999 김천대학교 논문집 Vol.20 No.-

The social education that is provided for the people will be an important part of the national growth in the 21 century. This study was taken to present the desirable direction that Kimcheon College Continuing Education has to make progress as a central organization with perceiving the importance of continuing education for the Kimcheon citizen. To achieve the objective of the study, examined a sample of 592 citizen and students from Kimcheon City and Kimcheon College. The survey revealed the following results : 1. Offer the effective operation of education policies and curriculums. 2. Perform the role of foreign language education center. 3. Introduce the saving credit system. 4. Operate the special lectures for the students of the high school graduating class after the national scholastic achievement test for university and college entrance. 5. Suppert the special skills education for high school students after-school hours. 6. Administer the new employment program. These results showed the desirable direction that the Kimcheon College Continuing Education has to take some actions for the Kimcheon citizen.