• Title/Summary/Keyword: Preservation method

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Comparison of Different Methods of Aortic Valve Conduit Xenograft Preservation in an Animal Experiment Model; Fresh Cryopreservation versus Acellularized Cryopreservation (동물 실험 모델에서 적용한 이종대동맥판막도관의 조직보존방법 비교; 신선 냉동보존과 무세포화 냉동보존)

  • Kim, Chang Young;Kim, Kyung-Hwan;Moon, Kyung Chul;Kim, Woong-Han;Sung, Si-Chan;Kim, Yong-Jin
    • Journal of Chest Surgery
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    • v.43 no.1
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    • pp.11-19
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    • 2010
  • Background: The commercially used vascular xenografts have some problems such as calcification, fibrosis and tissue degeneration that are associated with inflammatory and immunologic reactions. We compared two methods of xenograft preservation (fresh cryopreservation versus acellularized cryopreservation) of goat aorta. Material and Method: Aortic valved xenografts were harvested from adult pigs, and these were preserved using fresh cryopreservation (FC group, n=4) or acellularized crypreservation (AC group, n=4). These xenografts were implanted into adult goats. There were 2 short-term survivors (less than 100 days) and 2 long-term survivors in each group. These xenografts were explanted and they underwent microscopic examination. Result: The goats survived 31, 40, 107 and 411 days in the FC group and the other goats survived 5, 40, 363 and 636 days in the AC group. All the short-term survivors in each group expired because of rupture at the proximal anastomosis site. Marked neutrophil infiltration was observed in the FC group FC and lymphocytes were observed in the AC group. There were no differences in the occurrence of calcification, fibrosis and thrombosis among the groups. Conclusion: Some goats survived more than 100 days after the xenograft implantation irrespective of the methods of preservation. Because severe tissue degeneration developed in both groups, we think these methods are not appropriate for xenograft preservation of aorta. It was worth a preliminary trial for improving the preservation method or to modify the processing of xenografts.

Analysis of Formability of Magnesium Alloy using Finite Element Method (유한요소법에 의한 마그네슘 합금판의 성형성 해석)

  • Kang, Dae-Min;Park, Kyeong-Dong;Hwang, Jong-Kwan
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.3 no.2
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    • pp.60-66
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    • 2004
  • Finite element method is very effective method to simulate the forming processes with good prediction of the deformation behaviour. In this paper, It was focussed on the drawability factors on the square cup deep drawing by PAM-STAMP with using magnesium alloy to reduce car weight as well as to draw much attention from the viewpoint of environmental preservation high rigidity, In order to predict the effect of drawability factors, the relationships between punch load and punch stroke, the relationships between thickness strain and distance, and are used. According to this study, the results of simulation will give engineers good information to access the drawability of square cup deep drawing at warm temperature.

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Estimate of Compressive Strength for Concrete using Ultrasonics by Multiple Regression Analysis Method (초음파를 이용한 중회귀분석법에 의한 콘크리트의 압축강도추정)

  • Park, I.G.;Han, E.K.;Kim, W.K.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.11 no.2
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    • pp.22-31
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    • 1991
  • Various types of ultrasonic techniques have been used for the estimation of compressive strength of concrete structures. However, conventional ultrasonic velocity method using only longitudial wave cannot be determined the compressive strength of concrete structures with accuracy. In this paper, by using the introduction of multiple parameter, e. g. velocity of shear wave, velocity of longitudinal wave, attenuation coefficient of shear wave, attenuation coefficient of longitudinal wave, combination condition, age and preservation method, multiple regression analysis method was applied to the determination of compressive strength of concrete structures. The experimental results show that velocity of shear wave can be estimated compressive strength of concrete with more accuracy compared with the velocity of longitudinal wave, accuracy of estimated error range of compressive strength of concrete structures can be enhanced within the range of ${\pm}$10% approximately.

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Changes in Internal Pressure of Frozen Fruits by Freezing Methods (동결방법에 따른 냉동 과일의 내부압력 변화)

  • 정진웅;정승원;박기재
    • Food Science and Preservation
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    • v.10 no.4
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    • pp.459-465
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    • 2003
  • This study was carried out to investigate the changes in internal pressure according to various freezing methods, as basic research to protect the destruction of tissues when fruits and vegetables are frozen. The rate of weight loss, caused by the freezing of fruits and vegetables, was found to be the least (0.44∼1.38%) when the immersion freezing method was applied. The difference in the rate of weight loss was the highest when freezing methods were applied to watermelon, and the freezing rate of watermelon whose moisture contents were greater have relatively greater influence on the weight loss. The difference in internal pressures was the least and caused by the volume increase and decrease, when pear, apple, and melon were frozen using the immersion freezing method, while the diffeyence the greatest when the air-blast freezing method was used. As the freezing rate was greater, the internal pressure was less. However, the internal pressure of strawberry and watermelon was the greatest when the immersion freezing method was applied. Frozen without using the thermal equalizing method, the change in internal pressure of fruits was about 2 psig. In contrast, the internal pressure of watermelon applied with the thermal equalizing method was changed in a way similar to that of watermelon not applied with the method, but the former generated a certain level of internal pressure and maintained a significantly low level of internal pressure (about 1.3 psig). When thawed, the internal pressure of samples to which the thermal equalizing method was applied was less than that of what the thermal equalizing method was not applied to. In comparison with the application of multi-step thermal equalizing method, 3∼4 times of application of the thermal equalizing method to the freezing resulted in the decrease of fluctuation range of internal pressure.

Quality Evaluation of Ginger Dried using a Molecular Press Dehydration Method or Employing a Dehydration Liquid (분자압축탈수 방법과 탈수액을 이용한 건조생강의 품질평가)

  • Lee, Hyun-Suk;Kim, Byeong-Sam;Cha, Hwan-Soo;Kwon, Ki-Hyun
    • Food Science and Preservation
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    • v.17 no.4
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    • pp.478-486
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    • 2010
  • The qualities of ginger prepared by an MPD (molecular press dehydration) method using maltodextrin, or dried using reused dehydration liquid, or prepared by freeze-drying or hot-air drying, were compared in terms of approximate overall composition, color, water absorption index, water solubility index, total sugar level, reducing sugar concentration, antioxidant activity, and gingerol content. The approximate composition of ginger prepared by the MPD method was lower in overall biochemical content than were those of gingers prepared using other methods. Ginger prepared by the MPD method retained the original ginger color. The water absorption and solubility index of ginger prepared by the MPD method (using maltodextrin) were better than those of gingers dried using other methods. The total sugar content did not change noticeably upon processing. The reducing sugar content of ginger prepared by hot-air drying was low. The antioxidant activity of ginger prepared by the MPD method was higher than that of freeze-dried and hot air-dried ginger samples, with values lower than those of BHA (3(2)-t-Butyl-4-hydroxyanisole) and BHT (2,6-Di-tert-butyl-4-methylphenol). The gingerol content of ginger prepared by the freeze-drying method was higher than that of gingers prepared by other methods. However, ginger constituents were present in the dehydration liquid used in the MPD method. The results indicate that both the MPD method (using maltodextrin) and the use of reused dehydration liquid are efficient methods by which ginger can be dried.

Combined Modality Therapy with Selective Bladder Preservation for Muscle Invading Bladder Cancer (침윤성 방광암 환자에서 방광 보존 치료)

  • Youn Seon Min;Yang Kwang Mo;Lee Hyung Sik;Hur Won Joo;Oh Sin Geun;Lee Jong Cheol;Yoon Jin Han;Kwon Heon Young;Jung Kyung Woo;Jung Se Il
    • Radiation Oncology Journal
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    • v.19 no.3
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    • pp.237-244
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    • 2001
  • Purpose : To assess the tolerance, complete response rate, bladder preservation rate and survival rate in patients with muscle-invading bladder cancer treated with selective bladder preservation protocol. Method and Materials : From October 1990 to June 1998, twenty six patients with muscle-invading bladder cancer (clinical stage T2-4, N0-3, M0) were enrolled for the treatment protocol of bladder preservation. They were treated with maximal TURBT (transurethral resection of bladder tumor) and 2 cycles of MCV chemotherapy (methotrexate, crisplatin, and vinblastine) followed by $39.6\~45\;Gy$ pelvic irradiation with concomitant cisplatin. After complete urologic evaluation (biopsy or cytology), the patients who achieved complete response were planed for bladder preservation treatment and treated with consolidation cisplatin and radiotherapy (19.8 Gy). The patients who had incomplete response were planed to immediate radical cystectomy. If they refused radical cystectomy, they were treated either with TURBT followed by MCV or cisplatin chemotherapy and radiotherapy. The median follow-up duration is 49.5 months. Results : The Patients with stage T2-3a and T3b-4a underwent complete removal of tumor or gross tumor removal by TURBT, respectively. Twenty one out of 26 patients $(81\%)$ successfully completed the protocol of the planned chemo-radiotherapy. Seven patients had documented complete response. Six of them were treated with additional consolidation cisplatin and radiotherapy. One patient was treated with 2 cycles of MCV chemotherapy due to refusal of chemo-radiotherapy. Five of 7 complete responders had functioning tumor-free bladder. Fourteen patients of incomplete responders were further treated with one of the followings : radical cystectomy (1 patient), or TURBT and 2 cycles of MCV chemotherapy (3 patients), or cisplatin and radiotherapy (10 patients). Thirteen patients of them were not treated with planned radical cystectomy due to patients' refusal (9 patients) or underlying medical problems (4 patients). Among twenty one patients, 12 patients $(58\%)$ were alive with their preserved bladder, 8 patients died with the disease, 1 patient died of intercurrent disease. The 5 years actuarial survival rates according to CR and PR after MCV chemotherapy and cisplatin chemoradiotherapy were $80\%\;and\;14\%$, respectively (u=0.001). Conclusion : In selected patients with muscle-invading bladder cancer, the bladder preservation could be achieved by MCV chemotherapy and cisplatin chemo-radiotherapy. All patients tolerated well this bladder preservation protoco. The availability of complete TURBT and the responsibility of neoadjuvant chemotherapy and chemoradiotherapy were important predictors for bladder preservation and survival. The patients who had not achieved complete response after neoadjuvant chemotherapy and chemoradiotherapy should be immediate radical cystectomy. A randomized prospective trial might be essential to determine more accurate indications between cystectomy or bladder preservation.

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Environmental Survey Data Modeling Using K-means Clustering Techniques

  • Park, Hee-Chang;Cho, Kwang-Hyun
    • Journal of the Korean Data and Information Science Society
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    • v.16 no.3
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    • pp.557-566
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    • 2005
  • Clustering is the process of grouping the data into clusters so that objects within a cluster have high similarity in comparison to one another. In this paper we used k-means clustering of several clustering techniques. The k-means Clustering Is classified as a partitional clustering method. We analyze 2002 Gyeongnam social indicator survey data using k-means clustering techniques for environmental information. We can use these outputs given by k-means clustering for environmental preservation and environmental improvement.

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A Study of traditional 傷科學 (전통(傳統) 상과학(傷科學)에 대한 소고(小考))

  • Eun, Suk Min
    • The Journal of Korean Medical History
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    • v.21 no.1
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    • pp.77-81
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    • 2008
  • 상과, also called 정골과 in Korea, was a subclass of External Medicine. Of the many sub-fields belonging to Traditional Korean Medicine, 상과 specializes in technological aspects: therefore its preservation and accedence is emphasized. Traditional 상과학 primarily bases clinical diagnosis and treatment on 수기법. Tang dynasty 藺道人's "仙授理傷續斷秘方, the first medical text specializing in 상과, includes detailed description of the 復位, 夾板固定, training, and medicinal treatment stages of treating bone fracture. Jin dynasty 葛洪's "肘後備急方" introduces a fracture treatment method through 竹夾板固定.

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Environmental Survey Data Modeling using K-means Clustering Techniques

  • Park, Hee-Chang;Cho, Kwang-Hyun
    • 한국데이터정보과학회:학술대회논문집
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    • 2004.10a
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    • pp.77-86
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    • 2004
  • Clustering is the process of grouping the data into clusters so that objects within a cluster have high similarity in comparison to one another. In this paper we used k-means clustering of several clustering techniques. The k-means Clustering is classified as a partitional clustering method. We analyze 2002 Gyeongnam social indicator survey data using k-means clustering techniques for environmental information. We can use these outputs given by k-means clustering for environmental preservation and environmental improvement.

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The Fermemtation Control of Kimch (김치의 숙도조절)

  • 김미정;김순동
    • Journal of the East Asian Society of Dietary Life
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    • v.4 no.2
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    • pp.75-91
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    • 1994
  • As a part of the fermentation control scheme for the preservation and improvement of the quality of Kimch, this paper summerizes a result of the research into the cleaning method of materials, the fermentation of Kimch using cleaning materials, the search of lacticacidbacteria for starter, the seperation state of cell wall by starter, the fermentation of Kimchi in the airtight instrument and in the air controlled state. And it shows the influence on the growth of lacticacidbacteria when the herb-medicine is used as a sub-ingredients, and the effects on the quality of ginseng added Kimchi.