• 제목/요약/키워드: Integral Formation

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Oogenesis, Oocyte Degeneration and Sexual Maturation in Female Cyclina sinensis (Gmelin, 1971) (Bivalvia: Veneridae) in Korea

  • Chung, Ee-Yung;Koh, Chul-Hwan;Park, Gab-Man
    • Animal cells and systems
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    • 제11권2호
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    • pp.191-198
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    • 2007
  • The ultrastructure of germ cells and follicle cells during oogenesis, oocyte degeneration, reproductive cycle, and first sexual maturity in female Cyclina sinensis were investigated for clams collected from Simpo, Jeollabuk-do, Korea, by cytological and histological observations. Vitellogenesis occured by way of endogeous autosynthesis and exogenous heterosynthesis: vitellogensis occurred through a process of autosynthesis, which involves a combined activities of the Golgi complex, mitochondria, and rough endoplasmic reticulum. The process of heterosynthesis involved endocytotic incorporation of extraovarian precursors into the basal region of the early vitellogenic oocytes prior to the formation of vitelline envelope. The follicle cells appear to play an integral role in vitellogenesis and oocyte degeneration, functioning in phagocytosis and digestion of products originating from the degenerated oocytes: these functions can permit the transfer of yolk precursors needed for vitellogenesis. Follicle cells might have a lysosomal system for breakdown and might also resorb phagosomes in the cytoplasm for nutrient storage during oocyte degeneration.

Improved flame retardant performance of cellulose fibers following fluorine gas treatment

  • Kim, Jong Gu;Lee, Young-Seak;In, Se Jin
    • Carbon letters
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    • 제28권
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    • pp.66-71
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    • 2018
  • To improve the flame retardant performance of cellulose fibers, fluorine functional groups were introduced under various controlled fluorination conditions. The properties of the fluorinated cellulose fibers were analyzed by X-ray photoelectron spectroscopy and a thermogravimetric analysis. The fluorine functional group content in the fluorinated cellulose fibers increased with an increase in the fluorination temperature. However, the fluorination reaction increased the char yield and decreased the rate of degradation of the cellulose fibers by introducing donors, enabling the formation of a thick and compact char layer. Therefore, the flame retardant properties of cellulose fibers were improved following the fluorination treatment.

Deintercalation and Thermal Stability of Na-graphite Intercalation Compounds

  • Oh, Won-Chun
    • Carbon letters
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    • 제2권1호
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    • pp.22-26
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    • 2001
  • Na alloyed graphite intercalation compounds with stage 1 and 2 were synthesized using the high temperature and pressure technique. Thermal stability and staging transitions of the compounds were investigated depending on heating rates. The thermal stability and temperature dependence of the deintercalation compounds were characterized using differential scanning calorimeter (DSC) analyzer. Enthalpy of formations were confirmed at temperatures between 25 and $500^{\circ}C$, depending on the various heating rates. The structure ions and interlayer spaces of the graphite were identified by X-ray diffraction (XRD). Diffractograms of stages with non-integral (00l) values were obtained in the thermal decomposition process, and stacking disorder defects and random stage modes were observed. The average value of the interlayer C-C bond lengths were found approximately $2.12{\AA}$ and $1.23{\AA}$ from the diffractions. Based on the stage transition, the degree of the deintercalaton has a inverse-linear relationship against the heating rate.

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Application of Seismic Inversion to the Gas Field Development

  • Jo, Nam-Dae;Yang, Su-Yeong;Kim, Jae-Woo
    • 한국지구물리탐사학회:학술대회논문집
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    • 한국지구물리탐사학회 2009년도 특별 심포지엄
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    • pp.47-56
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    • 2009
  • Proper reservoir characterization is an integral part of formation evaluation, reserve estimation and planning of field development. Seismic inversion is a widely employed reservoir characterization tool that provides various rock properties of reservoir intervals. This study presents results of the inversion studies including Geostatistical Inversion carried out on the gas fields, offshore Myanmar. Higher resolution and multiple models can be produced by Geostatistical Inversion using input data such as pre-stack seismic data, well logs, petrophysical relationships and geological inferences for example reservoir shape and lateral extent. Detailed reservoir characterization was required for the development plan of gas fields, and the Geostatistical Inversion studies served as a basis for integrated geological modeling and development well planning.

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반도체 패키지의 칩셋과 다른 설계변수와의 연관성 평가 (Estimate on related to Chip Set and the other Various Parameter in Electronic Plastic Package)

  • 권용수
    • 한국산업융합학회 논문집
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    • 제2권2호
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    • pp.131-137
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    • 1999
  • Package crack caused by the soldering process in the surface mounting plastic package is evaluated by applying the energy release rate criterion. The package crack formation depend on various parameters such as chip set, chip size, package thickness, package width, material properties and the moisture content etc. The effects of chip set and the other parameters were estimated during the analysis of package cracks which were located in the edge of the upper interface of the chip and the lower interlace of the die pad. From the results, it could be obtained that the more significant parameters to effect the chip set are chip width.

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PANC-1세포에서 발현된 재조합 MT1-MMP의 효소 활성 (Activities of Recombinant MT1-MMP Expressed in PANC-1 Cells.)

  • 김혜난;정혜신
    • 생명과학회지
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    • 제18권3호
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    • pp.422-425
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    • 2008
  • Membrane-type 1 matrix metalloproteinase (MT1-MMP) is a membrane-associated zinc-dependent endoproteinase involved in extracellular matrix remodeling. MT1-MMP hydrolyzes ECM proteins like collagen and is involved in cancer cell migration and metastasis. Caveolins are integral membrane proteins and play a role in formation of caveolae, specialized membrane microdomains involved in clathrin-independent endocytosis. Recombinant MT1-MMP was transiently expressed in PANC-1 cells. Cells expressing recombinant MT1-MMP were able to hydrolyze collagen and migrate on collagen coated trans-well. Both subjacent collagen degradation and the cell migration conferred by recombinant MT1-MMP were inhibited by co-transfection of plasmids containing caveolin-1 cDNA. The results support that MT1-MMP is localized in lipid raft of the membrane and MT1-MMP activities in invasive cells could be inhibited by caveolin.

The Khitans: Corner Stone of the Mongol Empire

  • LANE, GEORGE
    • Acta Via Serica
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    • 제6권1호
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    • pp.141-164
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    • 2021
  • The Khitans were a Turco-Mongol clan who dominated China north of the Yangtze River during the early mediaeval period. They adopted and then adapted many of the cultural traditions of their powerful neighbours to the south, the Song Chinese. However, before their absorption into the Mongol Empire in the late 13th century they proved pivotal, firstly in the eastward expansion of the armies of Chinggis Khan, secondly, in the survival of the Persian heartlands after the Mongol invasions of the 1220s and thirdly, in the revival and integration of the polity of Iran into the Chinggisid Empire. Da Liao, the Khitans, the Qara Khitai, names which have served this clan well, strengthened and invigorated the hosts which harboured them. The Liao willingly assimilated into the Chinggisid Empire of whose formation they had been an integral agent and in doing so they also surrendered their identity but not their history. Recent scholarship is now unearthing and recognising their proud legacy and distinct identity. Michal Biran placed the Khitans irrevocably and centrally in mediaeval Asian history and this study emphasises their role in the establishment of the Mongol Empire.

La formación en valores para la construcción de la interculturalidad educativa

  • Garcia Lopez, Irma Eugenia;Jo, Young-Hyun
    • 이베로아메리카
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    • 제22권2호
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    • pp.123-151
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    • 2020
  • This paper shows a theoretical-reflective analysis on the importance of vocational training and value education to transition into models that are inclusive in cultural diversity, typical of the globalized and hyperconnected environment of modern societies. Interculturality is contextualized as a key element in linking teaching-learning processes with the uniqueness and problems associated with cultural ethnocentrism and alterity. In this sense, the work is part of a thematic review that contributes to the understanding, inclusion and recognition of cultural, racial and ethnic diversity in the different formal spaces of learning. As summary, value education and transversality are the basis for building educational interculturality in future generations.

GAS KINEMATICS AND PHOTOIONIZATION IN TYPE 1 AGNs WITH STRONG OUTFLOWS

  • KIM, CHANGSEOK;WOO, JONG-HAK;LUO, RONGXIN
    • 천문학회보
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    • 제45권1호
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    • pp.61.3-61.3
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    • 2020
  • We present spatially resolved outflows and photoionization for a pilot sample of 11 type 1 AGNs (z<0.3) based on the Gemini Multi-Object Spectrograph Integral Field Unit data. These AGNs were selected since we found strong outflow signatures in SDSS spectra. We focus on [OIII] and Hα emission lines to probe outflow kinematics by measuring line flux, velocity, and velocity dispersion at each pixel. We investigate characteristics of gas kinematics of type 1 AGNs and compare them with those of type 2 AGNs in our previous studies. Furthermore, by drawing BPT map, photoionization states will be also discussed. Based on the results, we discuss various implications on the impacts of outflows on star formation in host galaxies.

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Development Status of the DOTIFS: a new multi-IFU optical spectrograph for the 3.6m Devasthal Optical Telescope

  • Chung, Haeun;Ramaprakash, A.N.;Omar, Amitesh;Ravindranath, Swara;Chattopadhyay, Sabyasachi;Rajarshi, Chaitanya V.;Khodade, Pravin
    • 천문학회보
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    • 제39권1호
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    • pp.51.1-51.1
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    • 2014
  • DOTIFS is a new multi-object Integral Field Spectrograph (IFS) being designed and fabricated by the Inter-University Center for Astronomy and Astrophysics, Pune, India, (IUCAA) for the Cassegrain side port of the 3.6m Devasthal Optical Telescope (DOT). The telescope is constructed by the Aryabhatta Research Institute of Observational Sciences, Nainital (ARIES). Its main scientific objectives are the physics and kinematics of the ionized gas, star formation and H II regions in nearby galaxies. It is a novel instrument in terms of multi-IFU, built in deployment system, and high throughput. It consists of one magnifier, 16 integral field units (IFUs), and 8 spectrographs. Each IFU is comprised of a microlens array and 144 optical fibers, and has $7.4^{\prime\prime}{\times}8.7^{\prime\prime}$ field of view with 144 spaxel elements with a sampling of 0.8" hexagonal aperture. The IFUs can be deployed on the telescope side port over an 8' diameter focal plane by x-y actuators. 8 Identical, all refractive, dedicated fiber spectrographs will produce 2,304 R~1800 spectra over 370-740nm wavelength range with single exposure. Currently, conceptual and baseline design review had been done, and is in the critical design phase with a review planned for later this year. Some of the components have already arrived. The instrument will see its first light in 2015.

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