백서 척수후근절로부터 슈반세포의 효과적인 체외 배양법

김성민,이종호,김남열,안강민,최원재,최시호,차미주,이주영,황순정,장정원,명훈,최진영,서병무,정필훈,김명진 大韓顎顔面成形再建外科學會 2003 Maxillofacial Plastic Reconstructive Surgery Vol.25 No.4

Schwann cells(SCs), an important component of the peripheral nervous system, intract with nerous to mutually support growth and replication for the peripheral nerve regentation. Recently, ading SCs to the lumen of guidance channel is widely tried to improve regeneration or to make regeneration possible over otherwise irreparable gaps. however, it is not easy to isolate and multiplicate SCs as much as enough to help the axonal regeneration. For the allogeneic SCs source for tubular nerve guidance, we developed a little bit improved technique of harvesting and multiplicating SCs. by culturing dispersed dorsal root ganglia in specially designed medium with growth factors and serial processing, we repeatedlly generate relatively homogenous SC cultures. Our technique was compared with other methods of literature using immunostaining methods such as GFAP, S100, BDNF and the total SC count assessment at different time interval after primary culture.

라덱스 혼입률에 따른 철근콘크리트의 휨파괴 거동특성

정원경,김동호,이주형,임홍범,윤경구 江原大學校 産業技術硏究所 2002 産業技術硏究 Vol.22 No.A

Reinforced concrete(R/C) is commonly used to structures because they have many merits that compressive strength, economy and so on. However, reinforced concrete has a crack at the tensile section which is due to the relatively lower tensile strength than its compressive strength. Latex modified concrete(LMC) has higher tensile and flexural strength than the ordinary portland cement, due to the interconnections of hydrated cement and aggregates by a film of latex particles. The purpose of this study was to investigate the flexural behavior of reinforced concrete beam with latex modified concrete, having the main experimental variables such as concrete types(ordinary portland cement concrete, latex modified concrete), latex contents(0%, 15%), flexural steel ratios(0.012, 0.0235), and with/without shear reinforcement. The beam of LMC showed considerably higher initial cracking loads and ductility than that of OPC, but, similar to ultimate strength and deflection. This might be attributed to the interlocking of hydrated cement and aggregates by a film of latex particles, water retention due to hydrophobic, and colloidal properties of the latexes resulting in reduced water evaporation. The beam with latex modified concrete could be adopted at field for controlling and reducing the tensile crack due to its higher tensile strength.

오원천의 식물플랑크톤 군집에 대한 연구

주현수,김진,박종천,정원석,송현철,이용탁,이우범 國立麗水大學校 環境問題硏究所 2004 環境硏究論文集 Vol.6 No.-

We carried out a study on phytoplankton community at Owon stream, Jeollabukdo, Korea. The author have examined 83 taxa of the phytoplankton from researched area. These were composed of 5 classes, 11 orders, 21 families, 44 genera, 79 species, and 9 varieties. The composition of occurrence species were as follows: green algae are 48.2%, diatoms are 33.7%, blue green algae are 10.8% and etc(7.3%). Dominant species were Chlamydomonas angulosa, Pandorina morum, Coelastrum microporum, Scenedesmus quadricauda, Staurastrum gracile, Melosira varians, Me. italica, Synedra ulna, Sy. acus, Cocconeis placentula, and Cymbella tumida. The standing crops varied from 1,650cells/ℓ to 47,000cells/ℓ. Phytoplankton density of Owon stream were lower about 8.6 times to a 1,531 times than those of other lakes and rivers in Korea. So, to preserve the water quality in Owon stream we have to manage continuously on the nitrogen and phosphorus.

신경회로망을 이용한 이면비드 폭 예측에 관한 연구

정재원,김일수,박창언,김학형,서주환,김인주,심지연 한국공작기계학회 2008 한국공작기계학회 춘계학술대회논문집 Vol.2008 No.-

The development of robotic welding process is a very complex assignment because the system is affected by a number of process parameters which are very difficult to determine or predict in practice. The full automation welding has not yet been achieved partly because the mathematical model for the process parameters of a given welding task is not fully understood and quantified. Several mathematical models to control welding quality, Productivity, micro structure and weld properties in arc welding processed have been studied. However, it is not an easy task to apply them to the various practical situations because the relationship between the process parameters and the bead geometry is non-linear and also they are usually dependent on specific experimental result. Practically, it is difficult, but important to know how to establish a mathematical model that can predict the result of the actual welding process and how to select the optimum welding condition under a certain constraint. In this paper, an attempt has been made to develop an neural network model to predict the back-bead width as a function of key process parameters in the GMA (Gas Metal Arc) welding and to compare the developed models with the experimental results

재발성 류마티즘 환자에서 발작의 유발인자

주유철,이동민,양종태,신병철,임태영,서정균,정기영,최동헌,김원,조영신,고희관 조선대학교 2001 The Medical Journal of Chosun University Vol.26 No.2

Background and Objectives : Palindromic rheumatism (PR) is known to be triggered without any obviously inciting events in most patients, although, in a few cases, attacks have been noted to relate to another events such as weather change, childbirth, ingestion of certain foods, or over-exercise. The aim of this study was to characterize the triggering factors on palindromic attacks. Materials and Methods : We evaluated sixty-four patients with PR for the presence of triggering factors and the relationship between attacks and triggering factors by interview of patients. We considered that there was an probable association between episodes and PR, if episodes within 24 hours prior to PR had triggered at least 50% of all attacks and a definite association between episodes and PR, if episodes within 24 hours prior to PR had triggered 100% of all attacks. Results : In 15 patients (35.9%), there was a possible association between episodes of PR and initiating events. In 8 patients (12.5%), there was a definite association between episodes of PR and initiating events. The triggering factors were physical over-activity including exercise (19/64: 29.7%), foods, such as rawfish, crab, and chicken, including alcohol (19/96: 19.8%). However, there were no difference between the groups with and without the triggering factor in sex ratio, duration and onset of PR, the positive rate of rheumatoid factor and involved sites. Conclusion : Our observations showed that PR was triggered by physical over-activity more than in previous reports and hypersensitivity to foods was a causative factor in some patients with PR. However, patients with triggering factors had a similiar clinical profile to patients without triggering factors.

부산 지하철 2호선 소음 특성 연구

정경원,윤나나,김주인,곽진,김영태 한국환경과학회 2006 한국환경과학회지 Vol.15 No.3

라텍스개질 콘크리트의 물-시멘트비에 따른 건조수축 특성

정원경,김성환,김동호,이주형,이봉학 江原大學校 産業技術硏究所 2002 産業技術硏究 Vol.22 No.A

Drying shrinkage cracking which may be caused by the relatively large specific suface is a matter of grave concern for latex modified concrete(LMC) overlay and rapid-setting cement latex modified concrete(RSLMC) overlay. LMC and RSLMC were studied for field applications very actively in terms of strength and durability in Korea. However, there were no considerations in drying shrinkage. Therefore, the purpose of this dissertation was to study the drying shrinkage properties of LMC and RSLMC with the main experimental variables such as cement types(ordinary portland cement, rapid setting cement), water-cement ratios and curing days at a same controlled environment of 60% of relative humidity and 20℃ of temperature. The drying shrinkage for specimens was measured with a digital dial gauge of Demec. The test results showed that the drying shrinkage of LMC and RSLMC were considerably lower with low water-cement ratio, respectively. This might be attributed to the interlocking of hydrated cement and aggregates by a film of latex particles, water retention due to hydrophobic, and colloidal properties of the latexes resulting in reduced water evaporation.

일부 지역 주민에서 초기 신기능 저하의 지표로서 혈청 Cystatin C 농도의 유용성

원기범,김준섭,박준형,강혁주,이정호 동국대학교 의학연구소 2009 東國醫學 Vol.15 No.2

혈청 cystatin C농도는 혈청 creatinine농도에 비해 신기능을 정확히 반영한다고 알려져 있지만, 대규모 연구 자료가 제한적이었다. 따라서 저자는 다수의 일부 지역 주민을 대상으로 cystatin C를 creatinine과 비교하여 신기능의 지표로서 cystatin C의 유용성을 알아보고자 하였다. 2008년 7월부터 9월까지 포항지역의 건강 검진자 999명 (남자: 324명, 여자: 657명)을 대상으로 혈청 cystatin C, 혈청 creatmine, 나이, 체중을 측정하고, Cockcroft-Gault식으로 사구체 여과율을 계산하였다. 계산된 사구체 여과율을 National Kidney Foundation의 Kidney Disease Outcomes Quality Initiative (KDOQI)에서 제시한 만성 신장병 분류 기준에 따라 5단계로 분류하였지만 4단계 (중증의 사구체 여과율 저하) 및 5단계 (신부전 또는 투석) 에 포함되는 대상자들의 숫자가 적어 (4단계: 4명, 5단계: 1명) 연구 대상에서 제외하였다. 대상자들의 평균 나이는 52.1 ± 17.1 세, 평균 체중은 59.7 ± 11.3 Kg,평균 혈청 cystatin C농도는 0.9 ± 0.2 mg, 평균 creatinine 농도는 1.0 ± 0.2 mg/dL이었다. 사구체 여과율을 각 단계별로 비교해 본 결과는 다음과 같이 혈청 cystatin C농도는 1 단계 (정상 신기능)는 0.8 ± 0.1 mg, 2단계 (경도의 신기능 저하)는 0.9 U 0.1 mg, 3단계 (중등도의 신기능 저하)는 1.0 d=0.1mg로 각각 유의한 차이를 보였다 (p<0.05).혈청 creatinine농도는 1단계는 0.9 ± 0.2 mg/dL, 2단계는 0.9 ± 0.1 mg/dL, 3단계는 1.0 ± 0.1 mg/dL로 l단계와 2단계 간에 차이가 없었으나 (p>0.05), 2단계와 3단계 간에는 유의한 차이를 보였다 (p<0.05).혈청 cystatin C농도와 혈청 creatinine농도는 나이 (cystatin C: r=0.275, p<0.05; creatinine: r=0.300, p<0.05) 및 체중 (cystatin C: r=0.075, P<0.05; creatinine: r=0.162, p<0.05) 과 양의 상관 관계를 보였다. 혈청 cystatin C 농도는 성별 간의 차이가 없었고, 혈청 creatinine농도는 남성에서 유의하게 높았다. 혈청 cystatin C농도는 혈청 creatinine농도에 비해 초기 신기능 저하를 반영하는 유용한 지표라고 생각된다. Although serum cystatin C has been suggested to be a better alternative marker than serum creatinine for estimating renal function, there have been limited data about its superiority over creatinine in a large number of populations. The aim of this study was to evaluate cystatin C as a renal marker compared to creatinine in a large population of the local community. We measured serum cystatin C, creatinine, age, body weight from 999 volunteers (Male; 324, Female; 657) of a single local cohort, Phohang, from July to September, 2008, and then calculated the GFR according to Cockcroft Gault(CG) formula. The population was divided into five stages followed by the chronic renal disease classification presented by KDOQI. The numbers in stage 4 (severe renal impairment), and 5 (renal failure) were too small (4 in stage 4, 1 in stage 5) to perform statistical analysis, so we excluded them. The mean age was 52.1 ± 17.1, and body weight 59.7 ± 11.3 Kg; serum cystatin C 0.9 ± 0.2 mg/L; serum creatmine 1.0 ± 0.2 mg/dL; CG GFR 70.6 ± 19.1 ml/min/1.73 m^(2). The tests completed for the comparison among each stage suggested the following results; serum cystatin C levels in stage 1 (normal renal function), stage 2 (mild deterioration of renal function), and stage 3 (moderate deterioration of renal function) showed the significant differences (stage 1 vs 2: 0.8 ± 0.1 vs 0.9 ± 0.1, p<0.05; stage 2 vs 3: 0.9 ± 0.1 vs 1.0 ± 0.1, p<0.05). Serum creatinine levels showed no significant differences between stage 1 and stage 2 (stage 1 vs 2: 0.9 ± 0.2 vs 0.9 ± 0.1, p>0.05), but showed significant differences between stage 2 and stage 3 (stage 2 vs 3: 0.9 ± 0.1 vs 1.0 ± 0.1, p<0.05). Serum cystatin C and creatinine presented positive correlation between age (cystatin C: r=0.275, p<0.05; creatinine: r=0.300, p<0.05) and body weight (cystatin C: r=0.075, p<0.05; creatinine: r=0.162, P<0.05). Serum cystatin C levels showed no significant difference in sex, but serum creatinine levels were significantly higher in men than women. Serum cystatin C level is suggested to be more useful parameter than serum creatinine level to evaluate early renal impairment.

숯을 이용한 면직물의 천연염색

조원주,이정숙 한국의류산업학회 2004 한국의류산업학회지 Vol.6 No.6

In order to activate the characteristics of charcoal in fiber systems, this study was carried out to experiment with the particle size from two micrometers to ten micrometers of charcoal powders on cotton fabrics. The results obtained were as follows; The fabrics were dyed with gray colors by charcoal. The K/S values, that were indicative of the dye affinity, became higher as the increase of dyeing temperature, dyeing time, and dyeing concentration. Also it was con-firmed the morphology of the fiber surfaces adsorbed with the particle size from two micrometers to four micrometers of charcoal powder by scanning electronmicronscope. The cotton fabrics dyed by charcoals generally recorded 3-4 degree of wash fastness, 4-5 degree of dry-cleaning fastness, 4-5 degree acidic and alkaline perspirations and water fastness. In connection with the functional properties, cotton fabrics dyed with charcoal appeared that antibacterial, deodorization, far infrared emissivity were improved. Especially the deodorization was improved greatly by using charcoal.

최적 디지탈 서보계의 설계에 관한 연구

하영원,강정호,정주수 慶南專門大學 1995 論文集 Vol.23 No.1