냉매 오충전은 에어컨에서 빈번하게 발생하는 고장 모드 중 하나로, 적정 충전량 대비 부족 및 과충전 모두 냉방 성능의 저하를 유 발하므로 충전된 냉매량을 정확하게 판단하는 것이 중요하다. 본 연구에서는 퍼지 군집화 기법을 통한 정상상태 식별을 통해 냉매 오 충전량을 다중 분류하는 모델을 개발하였다. 정상상태 식별을 위해 에어컨 운전 데이터에 대해 이동 평균 간의 차이를 활용한 퍼지 군 집화 알고리즘을 적용하였으며, IFDR를 통해 기존 연구된 정상상태 판단 기법들과 식별 결과를 비교하였다. 이후, 시스템 내 상관성 을 고려한 mRMR을 이용해 특징을 선택하였으며, 도출된 특징을 이용해 SVM 기반의 다중 분류 모델이 생성되었다. 제안된 방법은 시험 데이터를 통해 만족할 만한 분류 정확도와 강건성을 도출하였다.
The mammalian yolk sac endoderm is an essential but understudied tissue that patterns and nourishes the embryo. This talk will present the isolation and characterization of several categories of rodent yolk sac endoderm stem cells. Specifically, we have isolated yolk sac endoderm stem cell lines from preimplantation embryos and from post-gastrulation yolk sacs. In both cases, we obtained two versions of stem cells that appear to differ in their degree of lineage maturation. I will discuss the relationship of these various isolates within the same species (rat or mouse), between species (rat vs. mouse), and with previously published isolates. I will then discuss potential applications in developmental biotechnology and toxicology as well as the human relevance of this research.
수술 후 체액 저류는 췌십이지장절제술 후 발생할 수 있는 중요한 합병증 중 하나로 이로 인해 사망률과 재원 기간이 증가할 수도 있다. 초음파내시경 유도 하 배액은 췌장 가성낭종의 치료 방법 중 하나이며 최근에는 수술 후 발생한 체액 저류 치료에 있어서도 성공적인 사례들이 보고되고 있다. 60세 여성이 한 달 동안 4 kg의 체중감소와 5일 전 부터 발생한 황달을 주소로 내원하였다. 복부 전산화단층 촬영 및 내시경 역행성 담췌관 조영술을 이용한 조직검사를 통하여 총담관암이 진단되어 췌십이지장절제술을 시행하였고 수술 2주째 발열, 복통, 백혈구 증가의 임상증상을 보였다. 진단을 위해 시행한 복부 전산화단층촬영에서 소낭의 위오목에 체액저류가 증가하여 내시경적 배액술을 시행하였고 이후 합병증 없이 증상이 호전되었다. 국내에서는 아직 췌십이지장절제술 후 발생한 체액 저류를 내시 경적 배액으로 치료한 증례가 보고된 바 없기에 문헌 고찰과 함께 보고하는 바이다.
To investigate genes differentially expressed in the venom of social and solitary wasps, a comparative transcriptome analysis was conducted. Subtractive expressed sequence tag (EST) libraries specific to the venom gland and sac (gland/sac) of a social wasp species, Vespa tropica and a solitary hunting wasp species, Rhynchium brunneum, was constructed by suppression subtractive hybridization. In BLASTx analysis, 41% and 56% of the total ESTs showed statistically best-matched hits (E ≤ 10-4) in the libraries of V. tropica and R. brunneum, respectively. Although the functional category analysis did not show remarkable differences in the distribution of functional categories between the two venom gland/sac cDNA libraries, perhaps due to the lack of functional information on many of the venom components, there were groups of genes that are specific to either V. tropica or R. brunneum. Venom allergen 5 and serine protease were found to be social wasp-specific venom transcripts. In contrast, venom peptides, metalloendopeptidases, arginine kinase and dendrotoxin were observed in solitary wasp at much higher frequencies.
Though hydrogen peroxide (H2O2) causes a deleterious effect to cells with its reactive oxygen species resulting in cell death, S-allyl cysteine (SAC, a bioactive organosulfur compound of aged garlic extract) has been known to have a cytoprotective effect. Few reported profiles of gene expression of H2O2 and SAC treated human cord blood derived mesenchymal stem cells (MSC). This study revealed changes in the profile of twenty-one genes grouped by oxidative stress, antioxidant, cell death, anti-apoptosis and anti-aging by quantitative real time PCR. A concentration of 100μM of SAC or 50μM of H2O2 was applied to MSC which show moderate growth and apoptosis pattern. H2O2 treatment enhanced expression of eleven genes out of twenty-one genes compared with that of control group, on the contrary SAC suppressed expression of eighteen genes out of twenty-one genes except C ros oncogene. SAC decreased expression of oxidative stress genes such as SOD1, CAT and GPX. These results seemed consistent with reports which elucidated over expression of NF-kB by H2O2, and suppression of it by SAC. This study will confer basic information for further experiments regarding the effects of SAC on gene levels.
To determine differential gene expression profiles in the venom gland and sac (gland/sac) of a solitary hunting wasp species, Eumenes pomiformis Fabricius (1781), a subtractive cDNA library was constructed by suppression subtractive hybridization. A total of 541 expressed sequence tags (EST) were clustered and assembled into 102 contigs. In total, 37 genes were found from the library by BLASTx search and manual analysis. A eumenitin-like venom peptide, EpVP1, occupied ca. 26% of the library. A novel venom peptide, EpDTX, shared sequence similarity with trypsin inhibitors and dendrotoxin-like venom peptides known as K+ channel blockers, implying it could be responsible for the paralysis of prey. As well as phospholipase A2 and hyaluronidase known to be main components of wasp venoms, several contigs encoding enzymes, including metalloendopeptidases and a decarboxylase likely involved in the processing and activation of venomous proteins, peptides, and neurotransmitters, were also isolated from the library. The presence of a gene encoding insulin-like growth factor binding protein suggests that solitary hunting wasps might control the prey to stay in larval stage by their venom. The abundance of these venom components in the venom gland/sac and alimentary canal was confirmed by quantitative real-time PCR.
포란한 성충 암컷 Tigriopus japonicus(요각류)를 내분비계 교란물질로 잘 알려져 있는 4-nonylphenol에 노출하여 생존율과 포란율의 변화를 살펴보았다. 실험생물은 2004년 4월 제주도 구안연안에서 플랑크톤망으로 쓸어 잡기로 채집한 후 실내순응을 한 달 동안 시켰다 치사율은 노출농도의 높아지면 증가하였으나 그 경향이 뚜렷하지 않았다. 반면, 노출 후 처음으로 치사한 개체가 발생하는 시기는 비처리군과 처리군에 따라 명백한 차이를 보였
A fixed biofilm reactor system composed of anaerobic, anoxic(1), anoxic(2), aerobic(1) and aerobic(2) reactor was packed with synthetic activated ceramic (SAC) media and adopted to reduce the inhibition effect of low temperature on nitrification activities. The changes of nitrification activity at different wastewater temperature were investigated through the evaluation of temperature coefficient, volatile attached solid (VAS), specific nitrification rate and alkalinity consumption. Operating temperature was varied from 20 to 5 ℃. In this biofilm system, the specific nitrification rates of 15 ℃, 10 ℃ and 5 ℃ were 0.972, 0.859 and 0.613 when the specific nitrification rate of 20 ℃ was assumed to 1.00. Moreover the nitrification activity was also observed at 5 ℃ which is lower temperature than the critical temperature condition for the microorganism of activated sludge system. The specific amount of volatile attached solid (VAS) on media was maintained the range of 13.6-12.5 mg VAS/g media at 20~10 ℃. As the temperature was downed to 5 ℃, VAS was rapidly decreased to 10.9 mg VAS/g media and effluent suspended solids was increased from 3.2 mg/L to 12.0 mg/L due to the detachment of microorganism from SAC media. And alkalinity consumption was lower than theoretical value with 5.23 mg as CaCO3/mg NH4 +-N removal at 20 ℃. Temperature coefficient (θ) of nitrification rate (20 ℃ ~ 5 ℃) was 1.033. Therefore, this fixed film nitrogen removal process showed superior stability for low temperature condition than conventional suspended growth process.