• Title/Summary/Keyword: Nuclei density

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Electrochemical Study of the Effect of Additives on High Current Density Copper Electroplating (고전류밀도 구리도금에서 첨가제에 따른 전기화학적 특성변화 연구)

  • Shim, Jin-Yong;Moon, Yun-Sung;Lee, Jae-Ho
    • Journal of the Microelectronics and Packaging Society
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    • v.18 no.2
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    • pp.43-48
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    • 2011
  • The maximum current density of copper electrorefining is 350 A/$m^2$ and the higher current density is required to promote the copper productivity. The 1000 A/$m^2$ high current density is possible when rotating disc electrode is employed to reduce diffusion thickness. The copper electroplating with 1000 A/$m^2$ is possible at 400 rpm. Thiourea and glue were used to improve the electrodeposition behaviors during copper electrorefining process. Potentiodynamic polarization tests were conducted to investigate the effects of additives on copper electrodeposition. Galvanostatic tests were also conducted at 1000 A/$m^2$. Copper were electroplated on cylindrical rotating electrodes to give the uniform flow on the electrode surface. The lowest surface roughness was obtained when 16 ppm thiourea was added to the electrolytes. The surface roughness was increased with glue concentration. The surface hardness was not influenced by addition of glue. The copper nuclei were getting smaller with thiourea concentration, however there is no glue effects on copper nucleation.

The effects of Yukmijihwang-Tang(UJT) on Dementia induced by focal brain ischemic injury in rats. (육미지황탕(六味地潢湯)이 국소(局所) 뇌허혈(腦虛血)로 유발된 기억력(記憶力) 손상(損傷) 백서(白鼠)에 미치는 영향(影響))

  • Kim, Kyung-Hwa;Kim, Kyung-Su;Kim, Kyeong-Ok
    • Journal of Oriental Neuropsychiatry
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    • v.17 no.3
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    • pp.45-56
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    • 2006
  • Objective: Yukmijibwang-Tang(UJT) has been used for Dementia derived by deficiency of Kidney-Yin in the oriental medicine. This study was planned to examine the effects of UJT on the memory loss induced by focal brain ischemic injury in the rats. Methods : Experimental groups were divided into 4 groups ; Normal group, Control group, UJT1 group and UJT2 group. Control group were no treated after focal brain ischemic injury. UJT1 group were administered UJT 0.3 $m{\ell}/kg$ to focal brain ischemic injuried rats for 21 days, UJT2 group were administered UJT 1.2 $m{\ell}/kg$ to focal brain ischemic injuried rats for 21 days. The present author observed the number of errors on the eight-arm radial maze task, the rate of correct choice on the eight-arm radial maze task, the values of density of Cresy1 violet- stained sections in the hippocampal CA1 and the values of density of Acetlycholine Esterase (AchE)stained nuclei in the hippocampal CA1. Results : The number of errors in the Eigth-arm radial maze task was significantly decreased in UJT1 group on 1, 2, 3, 5, 6days, And it was significantly decreased in UJT2 group on 1-6days compared with control group. The rate of correct choice in the eight-arm radial maze task was significantly increased in UJT1, UJT2 group compared with control group. The values of density of Cresyl violet-stained stained sections in the hippocampal CA1 were significantly increased in UJT1, UJT2 group compared with control group. The values of density of AchE in the hippocampal CA1 were increased in UJT1, UJT2 group compared with control group, but the values were not significant. Conclusions: The present author thought that Yukmijihwang-Tang could he used for curing dementia induced by focal brain ischemic injury.

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Liver Plasma Membrane and Nuclear $T_{3}$ Receptor Binding in the Obese (ob/ob) Mouse (비만 쥐(ob/ob mouse)의 간 세포막과 핵에 있는 $T_{3}$ 수용체의 결합능력에 관한 연구)

  • Kim, Kyung-Ah;Lachance, Paul A.
    • Journal of Nutrition and Health
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    • v.24 no.4
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    • pp.356-365
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    • 1991
  • $L-Triiodothyronine(T_3)$ binding to purified plasma membrane and to isolated nuclei from the same liver in obese(ob/ob) mice and their lean littermates was examined. The maximal binding capacity(Bmax) for $T_3$ receptor of liver nuclei, as compared to lean control, was significantly lower in the obese mouse$(obese 527{\pm}80fmol/mg\;DNA ; lean 883{\pm}62fmol/mg\;DNA)$, without an apparent difference in dissociation constant(Kd). The finding that obese mice have fewer liver nuclear $T_3$ receptors confirms previous reports. The Bmax and Kd of liver plasma membrane $T_3$ receptor were not significantly different between obese and lean mouse, which suggests no defect to be occurring in the function of the plasma membrane $T_3$ receptor and reinforces the view that the peripherally impaired thyroid hormone action in obese mice is a post plasma membrane receptor event. These results further support the hypothesis that the major defect of the thyroid hormone metabolism in genetic obesity occurs at the level of the nuclear receptor.

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The Ultrastructure of the Cutaneous Pigment Cells in the Amphibia (양서류 피부 색소세포의 미세구조)

  • 김한화;노용태;지영득;문영화
    • The Korean Journal of Zoology
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    • v.24 no.3
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    • pp.133-144
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    • 1981
  • The ultrastructures of the pigment cells in the Asiatic land salamander (Hynobius leechi) dorsal skin were obtained by means of electron microscope. The results were as follows; 1. The pigment cells of the epidermis consisted of the melanocytes in the germinal layer and of the melanophores distributing to the keratinocyte layer. The traits of these cells in the epidermis were as follows: A. The nuclei of the melanocytes were round or oval in shape and appeared as partly small or large infoldings of the nuclear envelope. B. Rough-surfaced endoplasmic reticulums and Golgi complexes were well developed in infranuclear cytoplasm. Many ribosomes were mainly distributed around the perinuclear portion. C. The melanosomes of the melanocytes were observed as a found or an oval shape and strong electron-dense or less electron-dense melanosomes were observed. D. The infoldings of the nuclear envelope in the melanophore were partly found deeper than those of the melanocyte. The cytoplasm of the melanophore filled with melanosomes caused organelles not to be observed in that. 2. The pigment cells in the dermis were composed of the xanthophores just beneath basement membrane and the melanophores in the connective tissue. The traits of these cells in the dermis were as follows: A. The xanthophores contained round or oval vesicles, and these vesicles were divided into 6 types (type I pterinosome, type II pterinosome, type III pterinosomes, type iv pterinosome, type V pterinosome, type VI pterinosome). B. Most of the nuclei of the melanophores in the dermis were elongate in shape, and a portion of the nuclear envelope was deep infolded. C. Becuase the cytoplasm was filled with the melanosomes of the same electron-density, organelles were not observed in the cytoplasm. D. Two processes of the melanophore in the dermis extended in parallel with a xanthophore and the cytoplasm in those processes were filled with the melanosomes.

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Star Formation Rate and AGN in Barred Galaxies (막대은하의 별탄생율과 활동성 은하핵)

  • Bang, Jun;Ann, Hong-Bae
    • Journal of the Korean earth science society
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    • v.30 no.1
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    • pp.69-80
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    • 2009
  • We investigate the dependence of star formation rate and Active Galaxy Nuclei (AGN) frequency on the bar properties, especially the bar strength, using SDSS DR6. To better represent the bar strength, we divided the bars into 6 classes according to their length and axial ratios. There seems to be a fairly good correlation between the star formation rate derived from $H{\alpha}$ emission lines and the bar strength, whereas there is no apparent correlation between the AGN activity and the bar strength. We interpret that the former correlation is due to the dependence of bar-driven gas inflow on the strength of bar. The lack of correlation between AGN and bar properties suggests that the accretion of gas onto a supermassive black hole (SMBH) is regulated by the interplay between the bar and SMBH. The frequency of AGN seems to be dependent on the background density but the star formation rate does not. It suggests that star formation is a localized phenomenon that is mostly determined by the gas density in a galaxy, while AGN activity is more closely related to the host property such as mass and luminosity that are thought to be dependent on the environment through the density-luminosity relation.

THE 18 ㎛ LUMINOSITY FUNCTION OF GALAXIES WITH AKARI

  • Toba, Yoshiki;Oyabu, Shinki;Matsuhara, Hideo;Ishihara, Daisuke;Malkan, Matt;Wada, Takehiko;Ohyama, Youichi;Kataza, Hirokazu;Takita, Satoshi
    • Publications of The Korean Astronomical Society
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    • v.27 no.4
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    • pp.335-338
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    • 2012
  • We present the $18{\mu}m$ luminosity function (LF) of galaxies at 0.006 < z < 0.8 (the average redshift is ~ 0.04) using the AKARI mid-infrared All-Sky Survey catalogue. We have selected 243 galaxies at $18{\mu}m$ from the Sloan Digital Sky Survey (SDSS) spectroscopic region. These galaxies then have been classified into five types; Seyfert 1 galaxies (Sy1, including quasars), Seyfert 2 galaxies (Sy2), low ionization narrow emission line galaxies (LINER), galaxies that are likely to contain both star formation and Active Galactic Nuclei (AGN) activities (composites), and star forming galaxies (SF) using optical emission lines such as the line width of $H{\alpha}$ or the emission line ratios of [OIII]/$H{\beta}$ and [NII]/$H{\alpha}$. As a result of constructing the LF of Sy1 and Sy2, we found the following results; (i) the number density ratio of Sy2 to Sy1 is $1.64{\pm}0.37$, larger than the results obtained from optical LF and (ii) the fraction of Sy2 in the entire AGN population may decrease with $18{\mu}m$ luminosity. These results suggest that most of the AGNs in the local universe are obscured by dust and the torus structure probably depends on the mid-infrared luminosity.

A study on environmental dependence with AGN activity with the SDSS galaxies

  • Kim, Minbae;Choi, Yun-Young;Kim, Sungsoo S.
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.52.2-52.2
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    • 2013
  • We explore the relative importance of the role of small-scale environment and large-scale environment in triggering nuclear activity of the local galaxies using a volume-limited sample with $M_r$ < -19.5 and 0.02 < z < 0.0685 selected from the Sloan Digital Sky Survey Data Release 7. The active galactic nuclei (AGN) host sample is composed of Type II AGNs identified with flux ratios of narrow emission lines with S/N > 6 and the central velocity dispersion of the sample galaxies is limited to have a narrow range between 130 < ${\sigma}$ < 200($km\;s^{-1}$), corresponding to 7.4 < $log(M_{BH}/M_{\odot})$ < 8.1 in order to fix the mass of the supermassive black hole at the center of its host galaxy. In this study, we find that the AGN fraction ($f_{AGN}$) of late-type galaxies are larger than of early-type galaxies and that for target galaxy with late-type nearest neighbor, $f_{AGN}$ starts to increase as the target galaxy approaches the virial radius of the nearest neighbor (about a few hundred kpc scale). The latter result may support the idea that the hydrodynamic interaction with the nearest neighbor as well as tidal interaction and merger also plays an important role in triggering the nuclear activity of galaxy. We also find that early-type cluster galaxies show decline of AGN activity compared to ones in lower density regions, whereas the direction of dependence of AGN activity for late-type galaxies is opposite.

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Review: Magnetite Synthesis using NanoFermentation (Review: NanoFermentation을 이용한 자철석 합성연구)

  • Moon, Ji-Won;Roh, Yul;Phelps, Tommy J.
    • Economic and Environmental Geology
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    • v.45 no.2
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    • pp.195-204
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    • 2012
  • Biomineralization has been explored for geochemical cycles and microbial tolerance mechanisms to metal toxicity. Here, we are introducing NanoFermentation which enables economic, environmentally friendly, requiring low input energy, and scalable manufacturing of nano-dimensioned magnetite. We are also focusing on controlling factors of crystallite size which can determine superparamagnetism and ferrimagnetism. Controlling factors are such as microbial species, temperature, incubation time, medium composition, substituted elements and their concentration, precursor type, reaction volume, precursor concentration density and their combinations. Crystallite size distribution of biomagnetite depends on the balance between nuclei generation and crystal growth. Biomineralization will elucidate elemental cycles on earth crust and microbial ecology as well as it will be applied to material sciences and devices via massive production of nanomaterials.

Study on Morphological Changes and TUNEL Reaction of Apoptotic Cells in Mouse Liver by Apoptosis Induction

  • Kwak, Soo-Dong;Yang, Je-Hoon;Koh, Phil-Ok;Seo, Deuk-Lok;Kang, Chung-Boo
    • Biomedical Science Letters
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    • v.8 no.3
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    • pp.179-184
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    • 2002
  • We investigated the morphological changes and TUNEL reaction of apoptotic cells in the liver of D-galactosamine (20 mg/mouse) and lipopolysaccharide (5 $\mu\textrm{g}$/mouse)-treated 30 mice (BALB/c), and in additioa also of apoptotic cells in kidney and spleen. The livers and other some organs of mice at 6, 12, 24, 48 and 72 hrs after treatment were collected and were fixed with 10% neutral formalin and paraffin sections were stained with hematoxylin-eosin or terminal deoxynucleotidly transferase-mediated dUTP nick end labeling (TUNEL) method. Morphological changes in apoptotic hepatocytes were chondensation of nuclei and density of cytoplasms, then the margination and pyknosis of chromatin, the formation of half-moon- or horse-shoe- or ship-like shapes of condensed chromatin mass, lastly formation of apoptotic bodies, disappearance of nuclear envelopes, decrease of stainability, then lysis and disappearance of apoptotic bodies. TUNEL positive reactions of hepatocytes were appeared first moderate in uncondensed hepatocytes, severe in condensed hepatocytes, moderate in chromatin-marginated hepatocytes. These reactions also were appeared moderate in hepatocytes with half-moon- or horse-shoe- or ship-like pyknotic chromatin mass or apoptotic bodies, and mild or negative in hepatocytes with lysed apoptotic bodies or with disappeared nuclear envelopes. Consequently these results suggested that TUNEL positive reactions of hepatocytes appeared at more early stages than appearance of chromatin condensation and disappeared at more early stage than disappearance of histological findings of apoptosis. We also confirmed that the differentiation of apoptotic cells from normal healthy cells of Kupffer cells and vascular endothelial cells in liver, reticular cells and lymphocytes in spleen and epithelial cells of tubules and ducts in kidney was impossible in H-E preparations but was possible in TUNEL preparations.

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Expression of Tryptophan Hydroxylase in the Hypothalamus and Hippocampus of Fasting and Anorexia Mutant Mice (절식시킨 생쥐와 식욕부진 돌연변이 생쥐의 시상하부와 해마에서의 Tryptophan Hydroxylase의 발현)

  • 김미자;김영옥;정주호
    • Journal of Nutrition and Health
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    • v.33 no.1
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    • pp.5-12
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    • 2000
  • The control of food intake is a complex phenomenon caused by interactions between central and peripheral control mechanisms. The hypothalamic and brain stem regions have been identified as centers for food intake and energy expenditure in animals and humans. Of these, the ventromedial and lateral hypothalamic areas are involved in the control of food intake. Also, large amounts of neurotransmitters known to be involved in feeding are present in the hippocampus. Paricularly, tryptophan hydroxylase(TPH), known as a factor in the control of food intake, is present in high levels in the paraventricular nucleus of the hypothalamus and the hippocampus. In this study, TPH expression levels in the hypothalamic and hippocampal regions of fasting, anorexia mutant, and control mice were compared using RT-PCR and immunohistochemical methods. Differences in body weight among the fasting, anorexia mutant, and control groups wire observed. No statistical significance was noted in the number of TPH-immunoactivity in the hypothalamic nuclei, but relatively higher populations of such fibers were observed in the fasting group : the control group yielded samples with an overall value of 170.3${\pm}$3.5 in terms of immunoreactivity-induced optical density, whereas the fasting group yielded a value of 168.3${\pm}$2.6, and the anorexia mutant group 171.3${\pm}$0.8(lower values represent higher immunoreactivity), In fasting mice, stained neuronal bodies were observed in the CA3 and dentate gyrus regions of the hippocampus, which was different from the hippocampal regions of the control and anorexia mutant mice. The RT-PCR procedures were performed using whole brains, precluding any statistically noticeable findings in relation to specific regions, although the fasting and anorexia mutant groups showed 123.3% and 102.9%, respectively, of the TPH mRNA level in the control. The overall results present evidences of the role of TPH in the decrease in food intake during fasting caused by exogenic factors and in genetically acquired anorexia. (Korean J Nutrition 33(1) : 5-12, 2000)

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