냉동ㆍ공조 장치에서 R-22와 자연냉매 R-290의 열전달과 사이클 특성

정재천,박기원,노건상,오후규 여수대학교 1998 論文集 Vol.12 No.2

A basic heat pump system was designed and manufactured, in which a pair of bare tube was constructed as main heat exchanger. New natural refrigerants R-290 and HCFC refrigerant R-22 were used. In this paper, cycle characteristics of global heat pump, evaporation and condensation heat transfer characteristics were studied and a basic data base for the optimum design of refrigeration and air-conditioning systems was obtained. On the condensing and evaporating heat transfer characteristics, the average heat transfer coefficient was obtained the higher value in R-290 than R-22 refrigerant. Characteristics of heat pump cycle were researched based on the compressor shaft power, cooling capacity and coefficient of performance. From these results, the heat pump cycle characteristics were more affected from the refrigerant properties and operating conditions. Considering the results, R-290 refrigerant has a sufficient ability to substitute R-22 due to its higher performance.

Original Articles : Clinical significance of occult hepatitis B virus infection in chronic hepatitis C patients

( Jae Young Jang ),( Soung Won Jeong ),( Sung Ran Cheon1 ),( Sae Hwan Lee1 ),( Sang Gyune Kim ),( Young Koog Cheon ),( Young Seok Kim1 ),( Young Deok Cho1 ),( Hong Soo Kim ),( So Young Jin ),( Yun Soo 대한간학회 2011 Clinical and Molecular Hepatology(대한간학회지) Vol.17 No.3

Background/Aims: We investigated the frequency of occult hepatitis B virus (HBV) infection in anti-hepatitis C virus (HCV)-positive individuals and the effects of occult HBV infection on the severity of liver disease. Methods: Seventy-one hepatitis B virus surface-antigen (HBsAg)-negative patients were divided according to their HBV serological status into groups A (anti-HBc positive, anti-HBs negative; n=18), B (anti-HBc positive, anti-HBs positive; n=34), and C (anti-HBc negative, anti-HBs positive/negative; n=19), and by anti-HCV positivity (anti-HCV positive; n=32 vs. anti-HCV negative; n=39). Liver biopsy samples were taken, and HBV DNA was quantified by real-time PCR. Results: Intrahepatic HBV DNA was detected in 32.4% (23/71) of the entire cohort, and HBV DNA levels were invariably low in the different groups. Occult HBV infection was detected more frequently in the anti-HBc-positive patients. Intrahepatic HBV DNA was detected in 28.1% (9/32) of the anti-HCV-positive and 35.9% (14/39) of the anti-HCV-negative subjects. The HCV genotype did not affect the detection rate of intrahepatic HBV DNA. In anti-HCV-positive cases, occult HBV infection did not affect liver disease severity. Conclusions: Low levels of intrahepatic HBV DNA were detected frequently in both HBsAg-negative and anti-HCV-positive cases. However, the frequency of occult HBV infection was not affected by the presence of hepatitis C, and occult HBV infection did not have a significant effect on the disease severity of hepatitis C. (Korean J Hepatol 2011;17:206-212)

본태성 고혈압쥐의 성장에 따른 뇌신경 세포막 Na, K-ATPase변동에 관한 연구

류석천,허강민,석정호,이재흔 충남대학교 의과대학 지역사회의학연구소 1992 충남의대잡지 Vol.19 No.1

To investigate the development change of synaptosomal Na, K-ATPase of hypertensive rat, Na, K-ATPase activity and ouabain binding sites were measured in the synaptosomal membrane prepared from 3 days-, 2 weeks-, 20 weeks- old Sprague-Dawley rats and spontaneously hypertensive rats Resulrs are as follows; 1. in the synaptosomal Na, K-ATPase of the normotensive and hypertensive rats, there were 2 kinds of isozymes, high affinity site(IC_(50):80-260 nM) and low affinity site(IC_(50):30-60 μM) 2. Synaptosomal Na, K-ATPase activity was increased in 2 and 20 weeks(high affinity site) or 2 weeks(low affinity site) old compared to that in 3 days old rat, and showed a tendency of decrease in 33 weeks old compared to that in 20 weeks old rats(high affinity site) in both groups. 3. Synaptosomal Na, K-ATPase activities of hypertensive rats were low in 3 days and 2 weeks old(high affinity site) or 3 days old (low affinity site) compared to that age groups of normotensive rats. 4. In the ouabain binding experiments, Kd value(0.1-0.2 μM) for ouabain was slightly increased with increase of age, but no difference between normotensive and hypertensive rats was detected. 5. The numbers of ouabain binding sites were increased in 2 weeks and 20 weeks old compared to those in 3 days old rats, and showed a tendency of decrease in 33 weeks old compared to that in 20 weeks old rats. 6. In the hypertensive rats, the number of ouabain binding sites was low in 3 days, compared to that of the correponding age group of normotensive rats. From the above results, it is suggested that in the spontaneously hypertensive rat, 1) synaptosomal Na, K-ATPase of high affinity site or low affinity site is increased significantly after birth as well as in the normotensive rat, 2) but significantly less than that of normotensive rats in early periods after birth and this may due to the low concentration in both high and low affinity Na, K-ATPase isozymes for ouabain.

하악골 골절수술에서 흡수성 골고정장치의 유용성

문재원,천지선,양정열 朝鮮大學校 附設 醫學硏究所 2005 The Medical Journal of Chosun University Vol.30 No.2

Introduction: The mandible is one of frequent facial bone fracture due to anatomic configuration like the nose and zygoma. When the mandible fractures occured, displacement of segments developed by pulling of strong muscles. And so for reduction of fractured mandible, rigid fixation needs for prevention of displacement. Metal plates and screws are most appropriate device to obtain for prevention of displacement in case of mandible fracture. But metal devices are hampered by temperature sensitivity and interference with radio-graphic imaging, leading corrosion, inflammatory response, the effect of atrophy of cortical bone, the need for a subsequent operation for removal. To overcome drawbacks of metal rigid fixation devices, there had been a continuous research on the development of a bioabsorbable skeletal fixation system using polymers of polylactic and polyglycolic acid. Material and Method: One hundred sixty eight fractures of the mandible in 110 patients (84 male patients and 26 female patients) were treated by open reduction and internal fixation using bioabsorbable plates and screws (BiosorbFX^(R), Bionix Implants, Inc., Finland). The average age is 36.5 years old. Total number used absorbable devices and 972 (182 plates and 790 screws). Patients were evaluated during the follow-up period, which ranged from 1 to 30 months. Common fracture sites are para symphysis (26%), body (19%) and angle (18%) which are experienced. Intermaxillary fixation placed before operation but removed after internal fixation of absorbable devices. After 5 days from operation, temporomandibular joint movement are started. We encountered no significant intraoperative difficulties obtaining placement of the devices. Result: None of patients has been experienced any implant-related complication including fracture instability or relapse, or radiographic evidence of osteolysis except one case of delayed osteomyelitis and four cases of intraoral infections. Conclusion: Absorbable devices have many advantage, that are lower infection rates, satisfactory strength, no metallic irritation, no restrictive growth of the neurocranium in pediatric patients, only one surginal procedure. Absorbable devices have some problems, such as slow and expense. But we experienced good results using absorbable devices to mandible fracture, and these results indicate that the use of bioabsorbable implants can be considered routinely for the fixation of mandible fractures.

Transarticualr portal를 이용한 주관절의 관절경술

김성재,박인섭,김주영,정재훈,류상욱,천용민 대한견.주관절학회 2003 大韓肩.주關節學會誌 Vol.6 No.2

엄지손가락 과다증을 동반한 수열에서 이엽피판을 이용한 제 1 갈퀴막 공간의 재건

문재원,천지선,양정열 朝鮮大學校 附設 醫學硏究所 2006 The Medical Journal of Chosun University Vol.31 No.2

Cleft hand is a rare disease that is characterized by absence of one or more digits, It was introduced by Abroise Pare in 1575. The cause of this is not identified yet. Polydactyly is defined as normally pentadactylous hand with excess digits, It was reported that the possible cause of polydactyly is increased folding of AER(apical ectodermal ridge). There are so rare cases that cleft hand is accompanied with preaxial polydactyly. We experienced a case of cleft hand with preaxial polydactyly. That case had narrowing of first web space and thumb polydactyly. Untilil now, there have been so many methods of reconstruction of web such as skin graft, z-plasty, dorsal and volar flap, etc. We reconstruct the first web with bilobed flap elevated from polydactylized thumb. As it has good results of functional and cosmetic properties, It's very useful to use accessory tissue from polydactylized finger such as our case.

수평 내면 핀관내에서 R-22와 대체 냉매의 증발 열전달 비교

노건상,박기원,정재천,오후규 여수대학교 1998 論文集 Vol.12 No.2

Worldwide energy consumption has been recently increasing enormously, especially in refrigeration and air conditioning industries. As a result of this increase, atmospheric hydrocarbon and other gas levels have increased so that they may be a source of world environmental problems. Therefore, new research was started to overcome the environmental problems, like the destruction of the ozone layer and the warming of Earth's temperature, by the use of natural refrigerants as substitutes for the freon refrigerant. In this paper, evaporation heat transfer of global heat pump using grooved inner tube was studied. New natural refrigerants R-290 and HCFC refrigerant R-22 were used. The local heat transfer coefficient was decreased according to the evaporation process. Moreover, the increment of heat transfer coefficient was found in R-290 refrigerant. Average heat transfer coefficient was obtained the higher value in R-290 refrigerant than R-22. Comparing the heat transfer coefficient between experimental result and simulation data of other's, the Shah's correlated equation was closely assimilated to the author's experimental results.

기니이픽 장관의 c-Kit 및 NK 1R 면역반응 세포구조에 대한 공초점 주사현미경적 연구

장인엽,김종중,문정석,김현곤,박찬국,전제열,전규배,조철희,유호진 조선대학교 2001 The Medical Journal of Chosun University Vol.26 No.1

Background and Objectives: Immunolabelling of interstitial Cajal(IC) cells in the intestinal wall has recently been developed by using a specific marker, the anti-c-Kit antibody. Substance-P is a well-known neurotransmitter in the gastro-intestinal tract. Since the gastro-intestinal wall structures have already been well documented in the guinea pig, immunohistochemistry was done for the c-Kit-positive IC network and substance-P receptor(NK1R) in an attempt to provide a morphological basis for the mechanism regulating gastro-intestinal movement. Materials and Methods: Cryosection and whole-mount preparations of guinea pig small intestine and colon were single and double immunolabelled using the anti-c-Kit and NK1R antibodies. Immunolabelled specimens were observed under a confocal laser scanning microscope. Results : According to a three dimensional reconstruction study, it was found that (1) the c-Kit-positive celluar networks were widely distributed in the intestinal wall, (2) c-Kit-positive celluar networks encircled the ganlion, with strands in reticular configurations, and (3) the c-Kit-positive cells showed colocalization with NK1R in circular muscle(CM), not myenteric plexus(MY). Conclusion: The charateristic profiles of IC containing c-Kit-positive celluar networks and the relationship between c-Kit-positive and NK1R-positive structures provide a morphological basis upon the mechanism regulating gastro-intestinal motility.

차나무의 품종, 부위, 채취시기에 따른 향기생성 효소의 활성과 향기배당체의 함량

정재천(Jae-Cheon Jeong),최정연(Jeong-Youn Choi),최문희(Moon-Hui Choi),손영란(Young-Lan Son),조정용(Jeong-Yong Cho),김선재(Seon-Jae Kim),문제학(Jae-Hak Moon),박근형(Keun-Hyung Park),마승진(Seung-Jin Ma) 한국차학회 2012 한국차학회지 Vol.18 No.4

Enzymatic activities and amounts of aromatic precursors, which are related with aroma formation in fermanted tea, were indirectly measured in vanious cultivars (Korean native cultivar, Taicha No.12, Yabukita), harvest time (May, July, September), and parts (aged leaves, young leaves, stem) by means of crude enzyme assay. Enzyme activities related to aroma formation in stems and young leaves were higher than those in aged leaves. Activities in parts harvested in September and July were higher than in those harvested in May. Total amounts of aromatic precursors were higher in young leaves than those in aged leaves from each cultivar. Amounts of precursors of geraniol and methyl salicylate were much higher in each part of Taicha No.12 than those of Yabukita, although much greater amounts of benzyl alcohol and 2-phenylethanol were liberated from Yabukita.

차나무 유래의 조효소와 재고녹차를 이용하여 제조한 차 향기추출물의 피부미용효과

정재천(Jae-Cheon Jeong),고기봉(Gi-Bong Ko),조정용(Jeong-Yong Cho),김선재(Seon-Jae Kim),문제학(Jae-Hak Moon),박근형(Keun-Hyung Park),마승진(Seung-Jin Ma) 한국차학회 2014 한국차학회지 Vol.20 No.1

본 연구에서는 차나무(C. sinensis)유래 조효소와 상품성이 하락한 재고녹차를 반응시켜 생성된 향기성분의 피부미용관련 효능을 검정함으로써 상품성 및 산업적 활용도가 낮은 재고녹차 및 향기생성 조효소의 산업적 이용 가능성을 확인하고자 하였다. 그 결과, elastase 저해 활성 및 UV-A의 피부세포 사멸에 대한 보호 효과 등 피부미용 관련 효과는 재고녹차 및 발효차 보다 차나무 유래 조효소와 재고녹차를 반응시켜 제조한 차의 향기추출물에서 가장 높게 나타났다. 또한, 이러한 결과는 피부관련 효능이 높은 것으로 확인된 linalool oxide, Z-3-hexenol, methyl salicylate 등의 발효차 유래 향기성분 함량이 재고녹차 및 발효차 보다 조효소와 재고녹차를 반응시켜 제조한 차에 높은 데에 기인한 것으로 판단되었다. 한편, 차나무 유래 조효소와 재고녹차를 이용한 차 제조시 향기성분이 최대로 생성될 수 있는 효소와 녹차의 반응, 추출 조건 및 각 조건으로 제조된 향기추출물의 피부미용효과를 탐색하였다. 그 결과, 조효소 분말과 추출 buffer의 비율 1:30 (w/v)의 조건에서 추출한 조효소액을 활용하여 재고녹차와 6시간 반응시켜 차를 제조한 후 SD방법으로 향기추출물을 제조하는 것이 가장 유리할 것으로 판단되었으며 이 추출물을 이용한 피부미용 관련 산업 소재로의 이용 가능성이 매우 높음을 확인하였다. Crude enzymes from tea plants contain various enzymes, such as glycosidase, which hydrolyze the aroma precursors of tea to liberate a variety of aroma compounds. To increase the industrial utilization of crude tea enzymes and inventory green tea, the skin care effects and the volatile compound compositions of aroma extracts prepared from inventory green tea after a reaction with the crude enzyme were examined. The aroma extracts of the inventory green tea after the reaction showed higher activities in the elastase inhibition assay and greater protection of fibroblasts from UVA-induced cytotoxicity than that of black tea and inventory green tea. The amount of volatile compounds related to fermented tea aroma, such as linalool oxide, Z-3-hexenol, geraniol, methyl salicylate etc. which showed strong skin care effects, were higher in the aroma extracts of inventory green tea after the reaction than that of black tea and inventory green tea. These results suggest the aroma extracts of inventory green tea after a reaction with the crude tea enzyme could be used as a functional material in the cosmetic industry, which could increase the industrial utility of inventory tea.