• 제목/요약/키워드: cluster differentiation

검색결과 151건 처리시간 0.028초

개불(Urechis unicinctus) 자성생식세포의 분화과정에 관한 미세구조연구 (The Differentiation of the Female Gonial Cell in Echiuroid (Urechis unicinctus): A Fine Structural Study)

  • 최임순;신길상;주충노;황대연
    • Applied Microscopy
    • /
    • 제18권1호
    • /
    • pp.77-91
    • /
    • 1988
  • Since the Urechis unicinctus-oocyte grows asynchronously in the body fluid, various oocytes in developmental stages can be prepared from each individual. The oocytes obtained from the coelomic fluid are then classified into five developmental stages according to the fine structural features. The earlier oocytes (${\sim}18{\mu}m$) form cluster and thereafter the oocytes grow singly without a distinct support of somatic cell, such as accessory cell or matrix cell. The yolk granules begin to appear already in the oocyte of cluster stage, however, the typical yolk was observed at the stage IV. Therefore, it was suggested that the yolk deposition is correlated with the coelomic fluid. The mature oocyte measured about $150{\mu}m$ produces the invagination not only on oolemma(indentation) but also on nuclear envelope. After the formation of the indentation, the mature ooytes are stored in storge sacs. The fine structural features were combined in aspect of structural concept of light microscopical observation.

  • PDF

제품, 서비스, 융합제품서비스의 소비자 니즈 비교 분석 :아마존 온라인 리뷰를 중심으로 (Comparative Analysis of Consumer Needs for Products, Service, and Integrated Product Service : Focusing on Amazon Online Reviews)

  • 김성범
    • 한국콘텐츠학회논문지
    • /
    • 제20권7호
    • /
    • pp.316-330
    • /
    • 2020
  • 이 연구는 텍스트 마이닝을 사용하여 하드웨어 제품에 대한 리뷰, 서비스 상품에 대한 리뷰, ICT분야의 하드웨어와 클라우드 서비스가 융합된 형태의 상품을 대상으로 소비자 리뷰를 분석한다. 분석을 위해 각 리뷰의 키워드를 도출하고 토픽 도출에 사용된 단어의 차별성을 찾는다. 마지막으로 전체 리뷰를 대상으로 군집분석을 실시하고 각각의 상품군의 리뷰가 어떤 군집에 속하는지를 검토한다. 이 연구를 통해서 각 상품의 유형별로 특화되어 사용된 핵심어를 도출하였고, 토픽모델링을 사용하여 제품과 서비스의 특성을 표현하는 주제를 도출하였다. 서비스 상품 리뷰에서는 공급자의 우수성을 의미하는 professional, technician과 같은 핵심어를 도출하였고, 융합제품서비스상품으로서 아마존 에코 리뷰에서는 favorite, fine, fun, nice, smart, unlimited, useful 등의 긍정적 의미의 형용사를 도출하였다. 군집분석을 사용하여 전체 리뷰를 분석하였고, 3개의 상품 유형별 리뷰가 배타적으로 서로 다른 각각의 군집에 속하는 결과를 발견하였다. 이 연구는 소비자의 니즈(needs)를 상품의 유형별로 온라인 리뷰를 이용하여 차이점을 분석하였고 실무적으로 상품 유형에 기반한 상품기획과 마케팅 프로모션 차별화의 필요성을 제시하였다.

중국 동관 IT 산업 클러스터의 글로벌 생산 네트워크 및 커플링 전략 (Global Production Network and Coupling Strategy of IT Industrial Clusters in Dongguan, China)

  • 이상빈;성을현;염명배
    • 한국융합학회논문지
    • /
    • 제8권7호
    • /
    • pp.39-46
    • /
    • 2017
  • 중국 경제성장에 핵심적 역할을 해왔던 광동성(廣東省) 동관시는 지리적으로 근접해 있는 홍콩을 이용하여 지속적인 경제발전을 추구해 왔다. 1980년대 초반은 홍콩으로부터 가전산업 관련 중소 다국적 기업이 동관지역에 진출하여 생산 공장을 세우고, 그 후 1990년 중반에는 대만의 PC제조업체의 진출이 잇따르면서 현재 동관에는 정보통신산업과 PC부품 및 전자산업 중심으로 지역 산업클러스터가 발전해 왔다. 동관시 산업클러스터 사례는 개혁개방 이후 중국 제조업 산업의 발전뿐만 아니라, 글로벌 시대에 해외직접투자와 아시아지역에서의 지역경제의 성장 및 산업발전과정의 연구에 대한 이론적 시사점을 줄 수 있는 지역적 사례 중의 하나다. 본 연구는 광동성 동관시 지역산업클러스터의 사례를 중심으로 이론적으로는 지역산업발전의 내생적 성장요인 분석(NMID) 혹은 글로벌 생산네트워크와의 외부적 연계성을 기초로 하는 산업의 지역적 분화(GPN)에 대한 이 두 관점을 상호 비교하고, 글로벌 융합전략을 설명하였다.

Genetic diversity of Indonesian cattle breeds based on microsatellite markers

  • Agung, Paskah Partogi;Saputra, Ferdy;Zein, Moch Syamsul Arifin;Wulandari, Ari Sulistyo;Putra, Widya Pintaka Bayu;Said, Syahruddin;Jakaria, Jakaria
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제32권4호
    • /
    • pp.467-476
    • /
    • 2019
  • Objective: This research was conducted to study the genetic diversity in several Indonesian cattle breeds using microsatellite markers to classify the Indonesian cattle breeds. Methods: A total of 229 DNA samples from of 10 cattle breeds were used in this study. The polymerase chain reaction process was conducted using 12 labeled primers. The size of allele was generated using the multiplex DNA fragment analysis. The POPGEN and CERVUS programs were used to obtain the observed number of alleles, effective number of alleles, observed heterozygosity value, expected heterozygosity value, allele frequency, genetic differentiation, the global heterozygote deficit among breeds, and the heterozygote deficit within the breed, gene flow, Hardy-Weinberg equilibrium, and polymorphism information content values. The MEGA program was used to generate a dendrogram that illustrates the relationship among cattle population. Bayesian clustering assignments were analyzed using STRUCTURE program. The GENETIX program was used to perform the correspondence factorial analysis (CFA). The GENALEX program was used to perform the principal coordinates analysis (PCoA) and analysis of molecular variance. The principal component analysis (PCA) was performed using adegenet package of R program. Results: A total of 862 alleles were detected in this study. The INRA23 allele 205 is a specific allele candidate for the Sumba Ongole cattle, while the allele 219 is a specific allele candidate for Ongole Grade. This study revealed a very close genetic relationship between the Ongole Grade and Sumba Ongole cattle and between the Madura and Pasundan cattle. The results from the CFA, PCoA, and PCA analysis in this study provide scientific evidence regarding the genetic relationship between Banteng and Bali cattle. According to the genetic relationship, the Pesisir cattle were classified as Bos indicus cattle. Conclusion: All identified alleles in this study were able to classify the cattle population into three clusters i.e. Bos taurus cluster (Simmental Purebred, Simmental Crossbred, and Holstein Friesian cattle); Bos indicus cluster (Sumba Ongole, Ongole Grade, Madura, Pasundan, and Pesisir cattle); and Bos javanicus cluster (Banteng and Bali cattle).

Insights into the Role of Follicular Helper T Cells in Autoimmunity

  • Park, Hong-Jai;Kim, Do-Hyun;Lim, Sang-Ho;Kim, Won-Ju;Youn, Jeehee;Choi, Youn-Soo;Choi, Je-Min
    • IMMUNE NETWORK
    • /
    • 제14권1호
    • /
    • pp.21-29
    • /
    • 2014
  • Follicular helper T ($T_{FH}$) cells are recently highlighted as their crucial role for humoral immunity to infection as well as their abnormal control to induce autoimmune disease. During an infection, na$\ddot{i}$ve T cells are differentiating into $T_{FH}$ cells which mediate memory B cells and long-lived plasma cells in germinal center (GC). $T_{FH}$ cells are characterized by their expression of master regulator, Bcl-6, and chemokine receptor, CXCR5, which are essential for the migration of T cells into the B cell follicle. Within the follicle, crosstalk occurs between B cells and $T_{FH}$ cells, leading to class switch recombination and affinity maturation. Various signaling molecules, including cytokines, surface molecules, and transcription factors are involved in $T_{FH}$ cell differentiation. IL-6 and IL-21 cytokine-mediated STAT signaling pathways, including STAT1 and STAT3, are crucial for inducing Bcl-6 expression and $T_{FH}$ cell differentiation. $T_{FH}$ cells express important surface molecules such as ICOS, PD-1, IL-21, BTLA, SAP and CD40L for mediating the interaction between T and B cells. Recently, two types of microRNA (miRNA) were found to be involved in the regulation of $T_{FH}$ cells. The miR-17-92 cluster induces Bcl-6 and $T_{FH}$ cell differentiation, whereas miR-10a negatively regulates Bcl-6 expression in T cells. In addition, follicular regulatory T ($T_{FR}$) cells are studied as thymus-derived $CXCR5^+PD-1^+Foxp3^+\;T_{reg}$ cells that play a significant role in limiting the GC response. Regulation of $T_{FH}$ cell differentiation and the GC reaction via miRNA and $T_{FR}$ cells could be important regulatory mechanisms for maintaining immune tolerance and preventing autoimmune diseases such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Here, we review recent studies on the various factors that affect $T_{FH}$ cell differentiation, and the role of $T_{FH}$ cells in autoimmune diseases.

홍삼 비사포닌 분획의 단핵세포 분화와 염증반응에 대한 억제효과 (Non-saponin fraction of red ginseng inhibits monocyte-to-macrophage differentiation and inflammatory responses in vitro)

  • 강보빈;김채영;황지수;최현선
    • 한국식품과학회지
    • /
    • 제51권1호
    • /
    • pp.70-80
    • /
    • 2019
  • 본 연구에서는 홍삼 비사포닌 분획(NSF)의 항 염증 효과를 마우스 대식세포와 인간유래 단핵세포에서 확인하였다. NSF는 마우스 대식세포에서 LPS로 유도된 NO, iNOS 그리고 COX-2의 양 뿐만 아니라 IL-6, $TNF-{\alpha}$, MCP-1과 같은 염증성 싸이토카인의 생성량을 유의적으로 감소시켰다. 인간 유래 단핵세포에서는 PMA에 의해 유도되는 대식세포로의 분화를 효과적으로 억제하면서 분화인자인 $CD11{\beta}$와 CD36의 발현을 유의적으로 감소시켰다. 마우스 대식세포에서와 마찬가지로 염증성 싸이토카인들의 생성량 또한 감소하였는데, 이러한 NSF의 항 염증 효과는 두 전사인자의 조절작용에 의한 것으로 사료된다. 즉 NSF는 $NF-{\kappa}B$의 핵으로 이동을 감소시킴으로써 전사활성을 억제하여 염증성 싸이토카인들의 발현을 저해하고 이와 반대로 Nrf2의 발현과 핵으로의 이동을 증가시켜 항산화 효소이면서 항 염증 작용을 나타내는 HO-1의 발현을 촉진하는 것으로 관찰되었다. 따라서 NSF는 $NF-{\kappa}B$와 Nrf2의 두 가지 신호전달체계를 조절함으로써 항 염증 작용을 나타냈으며 이를 홍삼 NSF의 항 염증 기작으로 보고하는 바이다.

동위효소 다형특성에 의한 누에 품종의 유연관계 (Genetic Relationships of Silkworm Stocks in Korea Inferred from Isozyme Analyses)

  • 성수일
    • 한국잠사곤충학회지
    • /
    • 제39권2호
    • /
    • pp.119-133
    • /
    • 1997
  • Isozyme was used to characterize general protein patterns of genetic relationships among 303 silkworm stocks preserved in National Sericultural and Entomology Research Institute, RDA. Six isozymes (esterase, acid phosphatase, alkaline phosphatase, amylase, glucose-6-phosphate dehydrogenase and sucrase) from hemolymph, midgut, and digestive juice were employed to construct dendograms(UPGMA method) using a polycrylamide gel electrophoresis. A cluster analysis revealed four major group, which were divided into several subgroups within each group, contained assemglages of Japanese and Chinese races. Especially, genetic differentiation in the first and second group was greatest rather than within Japanese and Chinese races repectively and was concordant with the hypothesis of phyletic sorting of initial variability in China many years ago. Hypothesized recent introgression between groups was also plausible, but the eviednce suggested bidirectional gene flow between the Chinese and the Japnaese lineages. Interpreting the results in light of evidence from the current study, the genetic diversity and relationship showed in Korean silkworm race, Hansammyun reflected early and independent evolution from the Chinese ancestor, limited addition of new variability and phyletic sorting within Korean peninsula more than 4,000 years.

  • PDF

장소마케팅과 쇼핑센터의 역할 - 동대문 의류시장을 중심으로 - (A Study on the Function of Shopping-Centers through Place Marketing - A Case Study of the Dongdaemun Fashion-Market -)

  • 소현재;강명구
    • 동굴
    • /
    • 제81호
    • /
    • pp.25-34
    • /
    • 2007
  • These days cities are in the stage of inter-competition and emboss the placeness which they have. The marketing is emphasized for urban regeneration in backward cities and the dominant position in the urban competition. This study focuses on the place marketing with potential factors which the places have. In addition, this study intends to research the marketing through showing centers and the method to commercialize the places with the factors to success, Planning-Group, Place Identity and Place Image, and Public-private Partnerships, in the case of the Dongdaemun Market. Finally, the study intends to show politic significance for preferable objects of place marketing for the network of the fashion-cluster, differentiation of the rapid productivity, the foreign information centers, the dongdaemun sewing association, and the merchant association as the consequence of comparable analysis.

Regulatory T Cells in B Cell Follicles

  • Chang, Jae-Hoon;Chung, Yeonseok
    • IMMUNE NETWORK
    • /
    • 제14권5호
    • /
    • pp.227-236
    • /
    • 2014
  • Understanding germinal center reactions is crucial not only for the design of effective vaccines against infectious agents and malignant cells but also for the development of therapeutic intervention for the treatment of antibody-mediated immune disorders. Recent advances in this field have revealed specialized subsets of T cells necessary for the control of B cell responses in the follicle. These cells include follicular regulatory T cells and Qa-1-restricted cluster of differentiation $(CD)8^+$ regulatory T cells. In this review, we discuss the current knowledge related to the role of regulatory T cells in the B cell follicle.

Mesodermal repression of single-minded in Drosophila embryo is mediated by a cluster of Snail-binding sites proximal to the early promoter

  • Park, Kye-Won;Hong, Joung-Woo
    • BMB Reports
    • /
    • 제45권10호
    • /
    • pp.577-582
    • /
    • 2012
  • single-minded (sim) is a master regulatory gene that directs differentiation in the central nervous system during Drosophila embryogenesis. Recent identification of the mesectoderm enhancer (MSE) of sim has led to the hypothesis that two Snail (Sna)-binding sites in the MSE may repress sim expression in the presumptive mesoderm. We provide evidence here that three Sna-binding sites proximal to the sim promoter, but not those of the MSE, are responsible for the mesodermal repression of sim in vivo. Using transgenic embryos injected with lacZ transgenes, we showed that sim repression in the mesoderm requires the three promoter-proximal Sna-binding sites. These results suggest that Sna represses the mesectodermal expression of sim by directly repressing the nearby promoter, and not by quenching adjacent transcriptional activators in the MSE. These data also showed how the MSE, lacking the three proximal Sna-binding sites, reproduced the endogenous pattern of sim expression in transgenic embryos.