• Title/Summary/Keyword: LTP

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The Study of Comparison between RPE-LTP and VSELP Speech Coder (RPE-LTP와 VSELP 음성부호화기의 비교에 관한 연구)

  • 박대덕;김화준;심재훈;유재희;정하봉;서정하
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.9
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    • pp.1838-1847
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    • 1994
  • Until recently, they decided the standard of the digital mobile communication speech coding method and competively developed the more detailed techniques in North America, Europe, Japan, etc. But, we have not yet determined. In this paper, we compared the RPE-LTP speech coding algorithm, standard in Europe, with the VSELP speech coding algorith, standard in North America, with respect to the soruce coding. We described the comprehensive verification and comparison with each speech coder, and discussed the improvement plan. Next, we also compared the number of computations which affects the real time processing seriously. Moreover, we performed the simulation with the Korean speech data, concreting the algorithm of each speech coder. Finally, we compared the performance of each speech coder with segmental SNR and 5-point MOS. The number of computations was calculated, and the result was that the number of multiplication computing times of VSELP speech encoder was the largest. With 26 speech data, the segmental SNR of VSELP was calculated larger than that of RPE-LTP. The 5-point MOS test was performed, and the result was that the basic speech quality of VSELP was equivalent or better than that of RPE-LTP.

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Increases in Effective Cleft Glutamate Concentration During Expression of LTP

  • Jung, Su-Hyun;Choi, Suk-Woo
    • The Korean Journal of Physiology and Pharmacology
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    • v.6 no.2
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    • pp.113-119
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    • 2002
  • Long-term potentiation (LTP) at hippocampal CA3-CA1 synapses is often associated with increases in quantal size, traditionally attributed to enhanced availability or efficacy of postsynaptic glutamate receptors. However, augmented quantal size might also reflect increases in neurotransmitter concentration within the synaptic cleft since AMPA-type glutamate receptors are not generally saturated during basal transmission. Here we report evidence that peak cleft glutamate concentration $([glu]_{cleft})$ increases during LTP, as indicated by a lessening of the blocking effects of rapidly unbinding antagonists of AMPA. The efficacy of slowly equilibrating antagonists remained unchanged. The elevated $[glu]_{cleft}$ helps support the increased quantal amplitude of AMPA-type EPSCs (excitatory postsynaptic currents) during LTP.

Dyeing Behavior of Low Temperature Plasma Treated Wool

  • Kan C.W.
    • Fibers and Polymers
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    • v.7 no.3
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    • pp.262-269
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    • 2006
  • In this paper, the effects of low temperature plasma (LTP) treatment on the dyeing properties of the wool fiber were studied. The wool fibers were treated with oxygen plasma and three types of dye that commonly used for wool dyeing, namely: (i) acid dye, (ii) chrome dye and (iii) reactive dye, were used in the dyeing process. For acid dyeing, the dyeing rate of the LTP-treated wool fiber was greatly increased but the final dyeing exhaustion equilibrium did not show any significant change. For chrome dyeing, the dyeing rate of the LTP-treated wool fiber was also increased but the final dyeing exhaustion equilibrium was only increased to a small extent. In addition, the rate of afterchroming process was similar to the chrome dyeing process. For the reactive dyeing, the dyeing rate of the LTP-treated wool fiber was greatly increased and also the final dyeing exhaustion equilibrium was increased significantly. As a result, it could conclude that the LTP treatment could improve the dyeing behavior of wool fiber in different dyeing systems.

Fast Screening of Harmful Disinfectants in Household Products via Low-Temperature Plasma Ionization-Mass Spectrometry

  • Lee, Hyoung Jun;Kweon, Gi Ryang;Yim, Yong-Hyeon
    • Mass Spectrometry Letters
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    • v.8 no.2
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    • pp.44-47
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    • 2017
  • Isothiazolinone derivatives are widely used in consumer products as disinfectants or preservatives, but there are growing concerns about their impact on human health. Therefore, rapid screening of these biocides is very important for proper control and regulation of potentially hazardous substances. To this end, low-temperature plasma (LTP) ionization mass spectrometry (MS) was investigated to demonstrate its potential for direct and selective analysis of isothiazolinones from sprayed aerosol samples. Benzisothiazolinone (BIT) was clearly identified from a commercial fabric deodorant using LTP ionization MS and MS/MS. LTP allowed selective ionization of BIT directly from the simply sprayed aerosol sample and illustrated its potential for fast screening without sample pre-treatments. Selective nature of LTP ionization, on the other hands, implicates use of LTP ionization MS as a general screening method for specific groups of hazardous chemicals in commercial products.

Osmotic Stress-Inducible Expression of a Lipid Transfer Protein Gene in Poplar

  • Lee, Hyo-Shin;Shin, Han-Na;Bae, Eun-Kyung;Lee, Jae-Soon;Noh, Eun-Woon
    • Korean Journal of Plant Resources
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    • v.21 no.3
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    • pp.204-209
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    • 2008
  • We have cloned an LTP gene (PoLTP1) from poplar (Populus alba ${\times}$ P. tremula var. glandulosa) suspension cells and examined changes in its expression levels in response to various stresses and ABA treatment. The full-length PoLTP1 cDNA clone encodes a polypeptide of 116 amino acids with typical characteristics of LTPs, notably a conserved arrangement of cysteine residues. Southern blot analysis indicate that two or three copies of the PoLTP1 are present in the genome of the investigated hybrid poplar. In addition, northern analysis of samples from soil-grown plants indicate that PoLTP1 is tissue-specifically expressed in the leaves and flowers. The gene is significantly up-regulated by treatment with mannitol, NaCl and ABA, but not by either cold or wounding. These results indicate that PoLTP1 is involved in osmotic stress responses in poplar plants and suspension cells.

Spatiotemporal Analysis of Hippocampal Long Term Potentiation Using Independent Component Analysis

  • Kim, T.S.;Lee, J.J.;Hwang, S.J.;Lee, Y.K.;Park, J.H.
    • Journal of Biomedical Engineering Research
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    • v.28 no.1
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    • pp.17-23
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    • 2007
  • Long-term potentiation (LTP) of synaptic transmission is the most widely studied model for learning and memory. However its mechanisms are not clearly elucidated and are a subject for intense investigation. Previous attempts to decipher cellular mechanisms and network properties involved a current-source density analysis (CSDA) of the LTP from small animal hippocampus measured with a limited number of microelectrodes (typically <3), only revealing limited nature of spatiotemporal dynamics. Recent advancement in multi-electrode array (MEA) technology allows continuous and simultaneous recordings of LTP with more than 60 electrodes. However CSDA via the standard Laplacian transform is still limited due to its relatively high sensitivity toward noise, inability of resolving overlapped current sources and sinks, and its requirement for tissue conductivity values. In this study, we propose a new methodology for improved CSDA. Independent component analysis and its joint use (i.e., Joint-ICA) are applied to extract spatiotemporal components of LTP. The results show that ICA and Joint-ICA are capable of extracting independent spatiotemporal components of LTP generators. The ICs of LTP indicate the reversing roles of current sources and sinks which are associated with LTP.

AlLTPs from Allium species represent a novel class of lipid transfer proteins that are localized in endomembrane compartments

  • Yi, Seung-In;Park, Mee-Yeon;Kim, Ju-Kon;Choi, Yang Do
    • Plant Biotechnology Reports
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    • v.3 no.3
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    • pp.213-223
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    • 2009
  • Lipid transfer proteins (LTPs) are widely distributed in the plant kingdom, but their functions remain elusive. The proteins AlLTP2-4 were isolated from three related Allium plants: garlic (A. sativum L.), Welsh onion (A. fistulosum L.), and Nanking shallot (A. ascalonicum L.). These novel proteins comprise a new class of LTPs associated with the Ace-AMP1 from onion (A. cepa L.). The AlLTP genes encode proteins harboring 132 common amino acids and also share a high level of sequence identity. Protein characteristics and phylogenetic analysis suggest that LTPs could be classified into five distinct groups. The AlLTPs were clustered into the most distantly related plant LTP subfamily and appeared to be restricted to the Allium species. In particular, the number of amino acids existing between the fourth and fifth Cys residue was suggested as a conserved motif facilitating the categorization of all the LTP-related proteins in the family. Unlike other LTPs, AlLTPs harboring both the putative C-terminal propeptide and N-terminal signal peptide were predicted to be localized to cytoplasmic vacuoles. When a chimeric GFP protein fused with both N-terminal and C-terminal AlLTP2 signal peptides was expressed in rice cells, the fluorescence signal was detected in the endomembrane compartments, thereby confirming that AlLTPs are an unprecedented intracellular type of LTP. Collectively, our present data demonstrate that AlLTPs are a novel type of LTP associated with the Allium species.

A Parametric Study on the Seismic Response Analysis of LNG Storage Tank with Disconnected Pile Foundation Subjected to Horizontal Seismic Input Considering Fluid-Structure-Soil Interaction (유체-구조물-지반 상호작용을 고려한 비결합 말뚝기초에 지지된 LNG 저장탱크의 수평지진입력에 대한 지진응답 매개변수해석)

  • Son, Il-Min;Kim, Jae-Min
    • Journal of the Earthquake Engineering Society of Korea
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    • v.28 no.1
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    • pp.21-32
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    • 2024
  • This study performed the seismic response analysis of an LNG storage tank supported by a disconnected piled raft foundation (DPRF) with a load transfer platform (LTP). For this purpose, a precise analytical model with simultaneous consideration of Fluid-Structure Interaction (FSI) and Soil-Structure Interaction (SSI) was used. The effect of the LTP characteristics (thickness, stiffness) of the DPRF system on the seismic response of the superstructure (inner and outer tanks) and piles was analyzed. The analytical results were compared with the response of the piled raft foundation (PRF) system. The following conclusions can be drawn from the numerical results: (1) The DPRF system has a smaller bending moment and axial force at the head of the pile than the PRF system, even if the thickness and stiffness of the LTP change; (2) The DPRF system has a slight stiffness of the LTP and the superstructure member force can increase with increasing thickness. This is because as the stiffness of the LTP decreases and the thickness increases, the natural frequency of the LTP becomes closer to the natural frequency of the superstructure, which may affect the response of the superstructure. Therefore, when applying the DPRF system, it is recommended that the sensitivity analysis of the seismic response to the thickness and stiffness of the LTP must be performed.

Long-Term Potentiation of Excitatory Synaptic Strength in Spinothalamic Tract Neurons of the Rat Spinal Cord

  • Hur, Sung Won;Park, Joo Min
    • The Korean Journal of Physiology and Pharmacology
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    • v.17 no.6
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    • pp.553-558
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    • 2013
  • Spinal dorsal horn nociceptive neurons have been shown to undergo long-term synaptic plasticity, including long-term potentiation (LTP) and long-term depression (LTD). Here, we focused on the spinothalamic tract (STT) neurons that are the main nociceptive neurons projecting from the spinal cord to the thalamus. Optical technique using fluorescent dye has made it possible to identify the STT neurons in the spinal cord. Evoked fast mono-synaptic, excitatory postsynaptic currents (eEPSCs) were measured in the STT neurons. Time-based tetanic stimulation (TBS) was employed to induce long-term potentiation (LTP) in the STT neurons. Coincident stimulation of both pre- and postsynaptic neurons using TBS showed immediate and persistent increase in AMPA receptor-mediated EPSCs. LTP can also be induced by postsynaptic spiking together with pharmacological stimulation using chemical NMDA. TBS-induced LTP observed in STT neurons was blocked by internal BAPTA, or $Ni^{2+}$, a T-type VOCC blocker. However, LTP was intact in the presence of L-type VOCC blocker. These results suggest that long-term plastic change of STT neurons requires NMDA receptor activation and postsynaptic calcium but is differentially sensitive to T-type VOCCs.

Problem Solving about Practical Engineering Education based on Analysis on Optimized Internal Flow of LTP Furnace and Uniformity of Temperature (LTP 퍼니스의 내부 유동 및 온도 균일도 최적화를 위한 실천공학교육적 문제해결)

  • Kim, Jin-woo;Youn, Gi-man;Jo, Eunjeong
    • Journal of Practical Engineering Education
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    • v.10 no.2
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    • pp.125-129
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    • 2018
  • This paper is about the numerical analysis on optimized internal flow of LTP furnace and uniformity of temperature. The LTP Furnace is the device that generates heat by electricity. And performs an annealing function for annealing the silicon wafer in the pre-semiconductor manufacturing process. Especially, the maximum temperature inside the chamber is maintained at a high temperature of about $400^{\circ}C$ to strengthen the wafer. When the process is completed at high temperature, the operation is repeated to reduce the temperature through the heat exchanger and carry it out. From this analysis, the ultimate goal is to derive the optimum design of the insulation volume supply/exhaust structure of the chamber through the flow analysis of the LTPS furnace. And to find cases for curriculum development.