• 대한수의학회지
• /
• 제40권3호
• /
• pp.515-524
• /
• 2000

The present study was conducted to investigate the phage types(PT) of Salmonella enteritidis(SE) isolated from animals and human patients in Korea during the period 1993-1999. SE were isolated from chickens including the layer and broiler, duck, rat, swine and human patients in nationwide scale. A total of 231 non-human and 14 human SE strains were phage typed and 80.4%(197/245) of SE isolates tested could discriminate as a ten SEPTs including the RDNC by the 10 standard phages, which were brought from the Central Public Health Laboratory in England. In analysing of phage types both animal and human SE isolates, SEPT 4(55.4%) was the most prevalent in domestic animals including the layer(39.3%) and broiler(64.5%), duck(55.5%), and swine(75.0%) since 1993. About 57% of the S enteritidis from human was SEPT 4. Along with SEPT 4, SEPT 1, SEPT 6a, SEPT 7 and SEPT 7a var, SEPT 9b, SEPT 15, SEPT 21b and SEPT 22 were also found from animal and human SE isolates. SEPT 4(40.0%) was isolated from frozen chicken meats imported from China along with SEPT 7 and 7a var strains in this study. In conclusion, SEPT 4 was the most predominant SEPT in our country regardless of animal or human hosts including the Che-Ju island and almost exclusively found in domestic poultry(layer and broiler). During the review period, SEPT 4 has already been spreading continually among the animal hosts since 1993.

• 대한지리학회지
• /
• 제36권3호
• /
• pp.233-246
• /
• 2001

주빙하환경의 지표로서 유상구조토의 의의를 밝히기 위하여 백록담 화구저의 유강구조토를 대강으로 지형 및 토양 특성을 조사하려다. 유상구조토의 평면형은 타원형이 많으며. 장경 42~200cm. 높이 9~27cm의 크기로서 25$m^2$의 범리에 17개가 20~40cm의 간격으로 분포한다. 초본식물의 근계로 덮여 있는 유상구조토의 내부는 상부의 암 갈색 토층과 하부의 갈색 토층으로 구분되며, 토양단면에는 동결교란의 양상이 나타난다. 토양은 점토와 실트의 세립 질이 31.2~65.6%를 차지하는데, 특히 암갈색 토층은 동상이 발생하기 쉬운 입도조성 보인다. 또한 건조밀도는 0.761 ~1.009g/㎤, 공극비는 1.420~2.008, 함수비는 24.2~68.8%로서 하부의 갈색 토층으로 내려갈수록 토양은 치밀하 고 건조해진다. 동계에 유강구조토는 콘크리트 상태로 동결하며, 최대동결심은 구조토의 정상부조부터 45cm이다. 동 결기에 암갈색 토층의 상부에는 빙층이 출현하나 현저한 동강을 일으키는 아이스렌즈와 같은 분리빙의 발달은 미약 하다. 이 시기에 유강구조포의 함수비는 전반적으로 증가하여 암갈색 토층에서는 73.7~118.0% 이른다. 유상구조토 토양의 컨스턴시는 함수비 72.8%가 액성한계에 해당하므로 해빙기에 암갈색 토층은 높은 유동성을 지니게 되며 동결고란작용을 입기 쉬워진다.

• 한국지반환경공학회 논문집
• /
• 제14권7호
• /
• pp.19-29
• /
• 2013

동토지역에서 지반의 역학적인 특징은 기존 토질역학이론과 다르기 때문에 동토지반 내 응력분포와 파괴조건을 묘사하기 위하여 기존 토질역학을 동토에 적용하는 것은 효과적이지 못하거나 적합하지 않다고 할 수 있다. 따라서, 동토지역에서 구조물의 설계 및 시공을 위해서는 동토역학에 관한 기술 자료의 수집 및 분석, 그리고 체계적이고 전문화된 연구가 필수적으로 요구된다. 극한지에서 나타나는 영구동토지역은 계절에 따라 활동층이 동결 융해를 반복하게 되며, 이에 따라 구조물에 영향을 끼치는 하중조건 또한 변화된다. 특히, 동토의 역학적인 성질들은 온도, 함수비, 입도분포, 상대밀도, 하중을 가하는 속도에 따라 민감하게 반응하기 때문에 동토지역 구조물 설계 및 시공에 있어 다양한 조건에 따른 동토의 역학적인 특징들을 신뢰성 있게 분석할 수 있는 방법이 필수적으로 요구된다. 본 연구에서는 동토의 전단강도 특성을 분석하기 위하여 영하 30도에서 작동 가능한 직접전단시험장비와 대형 냉동 챔버를 활용하였으며, 동결온도, 수직응력, 함수비 및 상대밀도를 달리하여 화강풍화토의 전단강도 특성을 분석하였다. 본 연구에 따르면 수직응력, 함수비 및 상대밀도는 동결온도 조건하에서 화강풍화토의 전단강도 특성에 영향을 끼치는 것으로 나타났다.

• Archives of Plastic Surgery
• /
• 제42권2호
• /
• pp.143-149
• /
• 2015

Background Adipose tissue damage of cryopreserved fat after autologous fat transfer is inevitable in several processes of re-transplantation. This study aims to compare and analyze the survivability of adipocytes after thawing fat cryopreserved at $-20^{\circ}C$ by using thawing methods used in clinics. Methods The survival rates of adipocytes in the following thawing groups were measured: natural thawing at $25^{\circ}C$ for 15 minutes; natural thawing at $25^{\circ}C$ for 5 minutes, followed by rapid thawing at $37^{\circ}C$ in a water bath for 5 minutes; and rapid thawing at $37^{\circ}C$ for 10 minutes in a water bath. The survival rates of adipocytes were assessed by measuring the volume of the fat layer in the top layers separated after centrifugation, counting the number of live adipocytes after staining with trypan blue, and measuring the activity of mitochondria in the adipocytes. Results In the group with rapid thawing for 10 minutes in a water bath, it was observed that the cell count of live adipocytes and the activity of the adipocyte mitochondria were significantly higher than in the other two groups (P<0.05). The volume of the fat layer separated by centrifugation was also measured to be higher, which was, however, not statistically significant. Conclusions It was shown that the survival rate of adipocytes was higher when the frozen fat tissue was thawed rapidly at $37^{\circ}C$. It can thus be concluded that if fats thawed with this method are re-transplanted, the survival rate of cryopreserved fats in transplantation will be improved, and thus, the effect of autologous fat transfer will increase.

• Asian-Australasian Journal of Animal Sciences
• /
• 제33권9호
• /
• pp.1411-1420
• /
• 2020

Objective: The aim of study was to investigate the effects of season and single layer centrifugation (SLC) before cryopreservation on post-thaw bull sperm quality in Thailand. Methods: Semen was collected from 6 bulls (Bos indicus) in summer, rainy season and winter 2014 through 2016. Semen characteristics, sperm morphology, sperm kinematics, viability, chromatin structure and mitochondrial membrane were evaluated. Meteorological data were available from the local meteorological station; Results: Season had an effect on semen characteristics in the raw ejaculate, with higher proportions of normal spermatozoa and lower abnormalities in winter than in the other two seasons. Sperm kinematics, viability, DNA fragmentation index, and mitochondrial membrane potential were not different between seasons. Sperm samples selected by SLC had greater normal morphology and a lower proportion with bent tails than controls and higher values of progressive motility (PRO), beat cross frequency, linearity, straightness, wobble (WOB), and lower values of slow motility, velocity average path (VAP), velocity curved line, and amplitude of lateral head displacement than controls. In addition, SLC-selection had a favorable effect on PRO, VAP, and WOB that differed among seasons. Conclusion: Our results suggested that these bulls were well adapted to their location, with season having an effect on sperm morphology. Moreover, SLC could be used prior to cryopreservation, regardless of season, to enhance normal morphology and kinematics of bull sperm samples without adversely affecting other parameters of sperm quality. However, there was considerable variation among bulls in DNA fragmentation index, mitochondrial membrane potential and sperm viability. In addition, SLC had a positive effect on sperm morphology and sperm kinematics, which could be expected to influence fertility.

• Archives of Plastic Surgery
• /
• 제36권4호
• /
• pp.417-421
• /
• 2009

Purpose: Dermatofibrosarcoma protuberans(DFSP) is a moderate - degree malignant tumor of soft tissue from dermis to fat layer with high recurrences(11% to 73%) due to its local infiltrative characteristic. Many debates and controversies in deciding accurate surgical margin were presented before, but references about depth of invasion and appropriate surgical excision level were not properly made out. Therefore, we tried to identify the degree of tissue invasion of DFSP. Methods: Twenty patients, including 8 patients with recurrent lesions, over last 10 years were reviewed retrospectively. Different surgical margins were applied according to the location and based on histopathologic result, we have defined as a 'deep tissue invasion' if there were infiltration of tumor cell into fascia or underlying muscle layer was present. All invaded tissue including dermis, fat, fascia and muscle were excised until no tumor cell was found during intraoperative frozen section biopsy. And comparative analysis of deep tissue invasion according to age, primary site, duration of disease and recurrence was done. Results: Thirteen patients(65%) showed deep tissue invasion and incidence was found to be increasing with age(over 30 years old). All patients with DFSP on head and neck region revealed deep tissue invasion followed by trunk(54%) and lower extremities(50%). There was no relationship between duration of disease and deep tissue invasion. Conclusions: It is clear that many cases of DFSP had a deep tissue invasion. And high prevalence of deep tissue invasion with age, primary site was intimately associated. So, underlying deep tissue must be completely examined and excised sufficiently throughout the operation for clear resection of DFSP with no recurrences, especially when age is over 30s and on head and neck region.

• 문화기술의 융합
• /
• 제10권3호
• /
• pp.909-914
• /
• 2024

본 연구에서는 로봇 비전용 영상 인식을 비롯한 다양한 AI 분야에서 널리 활용되는 전이학습에 대한 정량적 평가를 제시하였다. 전이학습을 적용한 연구 결과에 대한 정량적, 정성적 분석은 제시되나, 전이학습 자체에 대해서는 논의되지 않는다. 따라서 본 연구에서는 전이학습 자체에 대한 정량적 평가를 숫자 손글씨 데이터베이스인 MNIST를 기반으로 제안한다. 기준 네트워크를 대상으로 전이학습 동결층의 깊이 및 전이학습 데이터와 사전 학습 데이터의 비율에 따른 정확도 변화를 추적하였다. 이를 통해 첫번째 레이어까지 동결할 때 전이학습 데이터의 비율이 3% 이상일 경우, 90% 이상의 정확도를 안정적으로 유지할 수 있음이 확인되었다. 본 연구의 전이학습 정량 평가 방법은 향후 네트워크 구조와 데이터의 종류에 따라 최적화된 전이학습을 구현하는데 활용 가능하며, 다양한 환경에서 로봇 비전 및 이미지 분석 AI의 활용 범위를 확대할 것이다.

• Advances in pediatric surgery
• /
• 제7권2호
• /
• pp.130-136
• /
• 2001

The aim of this study was to evaluate the short-term outcomes of the trans anal one-stage pull-through procedure(TOP) in Hirschsprung's disease. Eight patients aged 3 weeks to 8 months with Hirschsprung's disease underwent this procedure. A rectal mucosectomy was performed from just proximal to dentate line to the level of peritoneal reflexion, where muscle layer was incised circumferentially. Rectosigmoid was mobilized out through the anus, and full-thickness frozen biopsy was taken for confirmation of ganglionic cells. After the rectal muscular cuff was divided longitudinally in the posterior aspect, aganglionic bowel was removed and ganglionic colon was anastomozed to the anus. The mean operating time was 161 minutes, and the mean hospital stay after operation was 3.8 days. Five patients had three to four bowel movement per day without other therapy at mean postoperative 39.2 days. Although long-term follow-up will be required, the TOP might be the new alternative surgical procedure for Hirschsprung's disease.

• 동력기계공학회지
• /
• 제11권3호
• /
• pp.22-28
• /
• 2007

Liquefied gas vaporizer is a machine to vaporize liquefied gas such as liquid nitrogen($LN_{2}$), liquefied natural gas(LNG), liquid oxygen($LO_{2}$) etc. For the air type vaporizer, the frozen dew is created by temperature drop (below 273 K) on vaporizer surface. The layer of ice make a contractions on vaporizer. The structure analysis on the heat transfer was studied to see the effect of geometric parameters of the vaporizer, which are length 1000 mm of various type vaporizer. Structure analysis result such as temperature variation, thermal stress and thermal strain have high efficiency of heat emission as increase of thermal conductivity. As the result, Frist, With-fin model shows high temperature distribution better than without-fin on the temperature analysis. Second, Without-fin model shows double contractions better then with-fin model under the super low temperature load on the thermal strain analysis. Third, Vaporizer fin can be apply not only heat exchange but also a stiffener of structure. Finally, we confirm that All model vaporizer can be stand for sudden load change because of compressive yield stress shows within 280 MPa on thermal stress analysis.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2016년도 추계 학술논문 발표대회
• /
• pp.13-14
• /
• 2016

In the modern construction industry, since numerous skyscrapers have been built, there have been sought for developing various kinds of methods for shortening a construction period. Therefore, many kinds of studies on some kinds of cold-weather concrete have been conducted actively for the purpose of a year-round construction. Accordingly, this research team once developed a double-layered bubble sheet as a surface-coated curing material for winter. And there have been raised some worries that some initial damages to frozen concrete caused by low temperature of reinforcing bars which are exposed out of the wall areas of a wall-type apartment during winter. Therefore, in this study, it is intended to find out clearly whether it is possible for concrete to be damaged initially or not by analyzing the temperature characteristics of the exposed reinforcing bars of the wall areas under the temperature conditions during winter.