• Title/Summary/Keyword: Selective Mechanism

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Selective Removal of Al(III) from Rare Earth Solutions Using Peas-based Activated Carbon

  • An, Fu-Qiang;Wu, Rui-Yan;Li, Min;Yuan, Zhi-Guo;Hu, Tuo-Ping;Gao, Jian-Feng
    • Journal of the Korean Chemical Society
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    • v.61 no.5
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    • pp.231-237
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    • 2017
  • Efficiently removing Al(III) from rare earth is very significant because even trace amount of Al(III) can cause serious harm to the rare earth materials. In this paper, a nitrogen-containing activated carbon, AC-P700, was synthesized using peas as raw materials. The AC-P700 was characterized by surface area analyzer, FT-IR, and XPS methods. The adsorption and recognition properties of AC-P700 towards Al(III) were investigated, and the recognition mechanism was also analyzed. The BET special surface area of AC-P700 was $1277.1m^2{\cdot}g^{-1}$, and the average pore diameter was 1.90 nm. The AC-P700 possesses strong adsorption affinity and excellent recognition selectivity towards Al(III). The adsorption capacity for Al(III) could reach to $0.53mmol{\cdot}g^{-1}$, and relative selectivity coefficients relative to La(III) and Ce(III) is 9.6 and 8.7, respectively. Besides, AC-P700 possesses better regeneration ability and reusability.

Functional Classification of Gene Expression Profiles During Differentiation of Mouse Embryonic Cells on Monolayer Culture

  • Leem, Sun-Hee;Ahn, Eun-Kyung;Heo, Jeong-Hoon
    • Animal cells and systems
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    • v.13 no.2
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    • pp.235-245
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    • 2009
  • Embryonic stem (ES) cells have a capability to generate all types of cells. However, the mechanism by which ES cells differentiate into specific cell is still unclear. Using microarray technology, the differentiation process in mouse embryonic stem cells was characterized by temporal gene expression changes of mouse ES cells during differentiation in a monolayer culture. A large number of genes were differentially regulated from 1 day to 14 days, and less number of genes were differentially expressed from 14 days to 28 days. The number of up-regulated genes was linearly increased throughout the 28 days of in vitro differentiation, while the number of down-regulated genes reached the plateau from 14 days to 28 days. Most differentially expressed genes were functionally classified into transcriptional regulation, development, extra cellular matrix (ECM),cytoskeleton organization, cytokines, receptors, RNA processing, DNA replication, chromatin assembly, proliferation and apoptosis related genes. While genes encoding ECM proteins were up-regulated, most of the genes related to proliferation, chromatin assembly, DNA replication, RNA processing, and cytoskeleton organization were down-regulated at 14 days. Genes known to be associated with embryo development or transcriptional regulation were differentially expressed mostly after 14 days of differentiation. These results indicate that the altered expression of ECM genes constitute an early event during the spontaneous differentiation, followed by the inhibition of proliferation and lineage specification. Our study might identify useful time-points for applying selective treatments for directed differentiation of mouse ES cells.

A Case of anterograde amnesia with hippocampal lesions following glufosinate intoxication (Glufosinate ammonium 중독 후에 발생한 해마 손상에 의한 선행성 기억상실 1례)

  • Seol Seung-Hwan;Park Hyeon-Soo;Ahn Jung-Hwan;Park Hee-Young;Lee Phil-Hyu;Kim Gi-Woon
    • Journal of The Korean Society of Clinical Toxicology
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    • v.4 no.1
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    • pp.61-64
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    • 2006
  • Glufosinate ammonium (GLA), a phosphinic acid derivate of glutamate, is a broad-spectrum contact herbicide. It structurally resembles glutamate, a typical excitatory amino acid in the central nervous system. In korea, the ingestion of GLA for suicidal attempt or accidental event has increased. The neurological complication of GLA intoxication are characterized by loss of consciousness, convulsion, or memory impairment. But, the exact mechanism of GLA toxicity is yet unknown. This report is about a patient with GLA intoxication who showed anterograde amnesia with selective bilateral hip-pocampal lesions supported GLA intoxication with literature reviews supported.

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Equlibrium and Kinetics of Metal Extraction by Amidoxime (Amidoxime에 의한 금속 추출 평형 및 추출 속도)

  • Shin, Jeong-Ho;Min, Seong-Kee;Jeong, Kap-Seop;Kim, Joo-Seok
    • Applied Chemistry for Engineering
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    • v.5 no.1
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    • pp.149-159
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    • 1994
  • The kinetics and equilibrium of metal extraction by benzamidoxime and phenylacetamidoxime-chloroform were investigated to apply amidoxime to metal extraction as chelating agent. The overall extraction constant extraction mechanism and selective extraction of copper were examined from the relation among extraction ratio, hydrogen ion concentration and extractant concentration. The experimental rate equation of copper extraction coincided with the theoretical rate equation and was expressed as $R_o=k{\overline{C}}_{HRo}(C_{Mo}/C_{Ho})^{1/2}$. The chemical species extracted was found to the type of ${\overline{CuR_2}}$.

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Analysis on Current and Optical Characteristics by Electronic Ink Loading Method in Charged Particles Type Display (대전입자형 디스플레이에서 전자 잉크 주입 방법에 따른 전류 및 광특성 분석)

  • An, Hyeong-Jin;Kim, Young-cho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.33 no.2
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    • pp.123-129
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    • 2020
  • We analyzed the drift current by charged particles according to the loading methods applied into a closed cell by electronic ink at a reflective-type display panel using an electrophoretic mechanism. For this experiment, various panels were fabricated with injection voltages for electronic ink taking values in the range -4~0 V. The size of each cell was 220 ㎛ × 220 ㎛ and height of the barrier rib was 54.28 ㎛. The electronic ink was fabricated by mixing electrically neutral fluid and single-charge white particles. Drift current was measured by moving charged particles. A biasing voltage of 6 V was applied to the display panel. As a result, the drift current was proportional to the injection voltage for electronic ink, but it decreased in case of an injection voltage above -3 V. Our experimentation ascertained that the concentration of charged particles injected into closed cells is controlled by the injection voltage and the selective injection of charged particles above movable q/m is possible.

Mitophagy: a balance regulator of NLRP3 inflammasome activation

  • Kim, Min-Ji;Yoon, Joo-Heon;Ryu, Ji-Hwan
    • BMB Reports
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    • v.49 no.10
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    • pp.529-535
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    • 2016
  • The NLRP3 inflammasome is activated by a variety of external or host-derived stimuli and its activation initiates an inflammatory response through caspase-1 activation, resulting in inflammatory cytokine IL-1β maturation and secretion. The NLRP3 inflammasome activation is a kind of innate immune response, most likely mediated by myeloid cells acting as a host defense mechanism. However, if this activation is not properly regulated, excessive inflammation induced by overactivated NLRP3 inflammasome can be detrimental to the host, causing tissue damage and organ dysfunction, eventually causing several diseases. Previous studies have suggested that mitochondrial damage may be a cause of NLRP3 inflammasome activation and autophagy, which is a conserved self-degradation process that negatively regulates NLRP3 inflammasome activation. Recently, mitochondria-selective autophagy, termed mitophagy, has emerged as a central player for maintaining mitochondrial homeostasis through the elimination of damaged mitochondria, leading to the prevention of hyperinflammation triggered by NLRP3 inflammasome activation. In this review, we will first focus on the molecular mechanisms of NLRP3 inflammasome activation and NLRP3 inflammasome-related diseases. We will then discuss autophagy, especially mitophagy, as a negative regulator of NLPP3 inflammasome activation by examining recent advances in research.

Mechanism of P-glycoprotein Expression in the SGC7901 Human Gastric Adenocarcinoma Cell Line Induced by Cyclooxygenase-2

  • Gu, Kang-Sheng;Chen, Yu
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.5
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    • pp.2379-2383
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    • 2012
  • Objective: To investigate possible signal pathway involvement in multi-drug resistant P-glycoprotein (P-gp) expression induced by cyclooxygenase-2 (COX-2) in a human gastric adenocarcinoma cell line stimulated with pacliaxel (TAX). Methods: The effects of TAX on SGC7901 cell growth with different doses was assessed by MTT assay, along with the effects of the COX-2 selective inhibitor NS-398 and the nuclear factor-KB (NF-KB) pathway inhibitor pyrrolidine dithiocarbamate (PDTC). Influence on COX-2, NF-KB p65 and P-gp expression was determined by Western blotting. Results: TAX, NS-398 and PDTC all reduced SGC7901 growth, with dosedependence. With increasing dose of TAX, the expression of COX-2, p65 and P-gp showed rising trends, this being reversed by NS-398. PDTC also caused decrease in expression of p65 and P-gp over time. Conclusion: COX-2 may induce the expression of P-gp in SGC7901 cell line via the NF-kappa B pathway with pacliaxel stimulation.

Effects of the pH Change of Ash Solution and the Addition of Chitosan on the Caesalpinia sappan Dyeing in the Simultaneous Mordanting with the Addition of Ash Solution (잿물 동시매염에 의한 소목의 염색에서 잿물의 pH 변화와 키토산 첨가가 염색성에 미치는 영향)

  • Seo, Hee-Sung;Jeon, Dong-Won;Kim, Jong-Jun
    • The Research Journal of the Costume Culture
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    • v.13 no.5 s.58
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    • pp.686-698
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    • 2005
  • In this study, simultaneous mordanting method of dyeing in the Caesalpinia sappan dye liquor mixed with the rice straw ash solution was employed. The dyeing effects were compared and reviewed according to the changes of dyeing mechanisms of pre-mordanting and simultaneous mordanting using ash solutions. By the direct addition of the ash solution, the pH of the liquor was abruptly changed. In the case of maintaining the pH value of the ash solution at about 7 or 8, compared to the pre-mordanting, $a^{*}$ values increased and $b^{*}$ values decreased. As a result, it is highly desirable in terms of selective emphasis on the reddish hue. The color development, differentiated from that obtainable by the dyeing of chitosan pre-treated fabric, was obtained due to the effect of the water soluble chitosan component on the dyeing mechanism.

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A Selective Message Synchronization Mechanism for Networked Virtual Environment (네트워크 가상환경에서의 선별적 메시지 동기화 기법)

  • Yun Chung-Ha;Paik Doo-Won
    • Journal of Korea Multimedia Society
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    • v.9 no.2
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    • pp.208-214
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    • 2006
  • Participants of a NVE(networked virtual environment) may have different hardwares and network environments, and to guarantee the fairness, messages of participants should be synchronized. A solution for the synchronization problem is to wait for a certain amount of time until the server processes the message. It is not easy to determine a suitable waiting period because of the trade-off between the fairness and the responsiveness. In this paper we propose a method to decide a waiting period by considering only the participants with small network delays and perform experiments for the performance evaluation. Experiments show that the proposed method leads to significant improvement of responsiveness, while retaining fairness.

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nArgBP2 as a hub molecule in the etiology of various neuropsychiatric disorders

  • Lee, Sang-Eun;Chang, Sunghoe
    • BMB Reports
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    • v.49 no.9
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    • pp.457-458
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    • 2016
  • Recent studies have strongly implicated postsynaptic scaffolding proteins such as SAPAP3 or Shank3 in the pathogenesis of various mood disorders, including autism spectrum disorder, bipolar disorder (BD), and obsessive-compulsive disorders. Neural Abelson-related gene-binding protein 2 (nArgBP2) was originally identified as a protein that interacts with SAPAP3 and Shank3. Recent study shows that the genetic deletion of nArgBP2 in mice leads to manic/bipolar-like behavior resembling symptoms of BD. However, the function of nArgBP2 at synapse, or its connection with the synaptic dysfunctions, is completely unknown. This study provides compelling evidence that nArgBP2 regulates the spine morphogenesis through the activation of Rac1/WAVE/PAK/cofilin pathway, and that its ablation causes a robust and selective inhibition of excitatory synapse formation, by controlling actin dynamics. Our results revealed the underlying mechanism for the synaptic dysfunction caused by nArgBP2 downregulation that associates with analogous human BD. Moreover, since nArgBP2 interacts with key proteins involved in various neuropsychiatric disorders, our finding implies that nArgBP2 could function as a hub linking various etiological factors of different mood disorders.