• Title/Summary/Keyword: Frequency selective

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Effects of [D-$Pen^2$, D-$Pen^5$]-enkephalin on the Neuronal Activity of Medial Vestibular Nuclear Neurons

  • Jang, Su-Jeong;Jeong, Han-Seong;Park, Jong-Seong
    • Biomedical Science Letters
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    • v.15 no.3
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    • pp.199-205
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    • 2009
  • This study was designed to investigate direct effects of [D-$Pen^2$, D-$Pen^5$]-enkephalin, a $\delta$-opioid receptor agonist on the neuronal activity of medial vestibular nuclear (MVN) neurons by whole-cell configuration patch clamp experiments. The spike frequency of MVN neuron was increased to $9.50{\pm}0.55$ (P<0.05) and $10.56{\pm}0.66$ (P<0.05) by 5 and $10{\mu}M$ [D-$Pen^2$, D-$Pen^5$]-enkephalin from the control level of $8.05{\pm}0.55$ spikes/sec, respectively (n=18). The resting membrane potential of the neurons was increased to $-37.86{\pm}0.92$ and $-36.97{\pm}0.97$ (P<0.05) from $-38.74{\pm}1.13\;mV$ by 5 and $10{\mu}M$ [D-$Pen^2$, D-$Pen^5$]-enkephalin, respectively. The amplitude of afterhyperpolarization was decreased to $23.78{\pm}0.65$ and $21.67{\pm}0.89$ (P<0.05) from $23.73{\pm}0.53\;mV$ by 5 and $10{\mu}M$ [D-$Pen^2$, D-$Pen^5$]-enkephalin, respectively. The spike width was changed to $2.22{\pm}0.08$ and $2.24{\pm}0.07$ from $2.20{\pm}0.08\;mV$ by 5 and $10{\mu}M$ [D-$Pen^2$, D-$Pen^5$]-enkephalin, respectively. After pretreatment of naltrindole, a highly selective 8-opioid receptor antagonist, [D-$Pen^2$, D-$Pen^5$]-enkephalin did not change firing rate, resting membrane potential, afterhyperpolarization amplitude, and spike width of MVN neurons. The above experimental results suggest that [D-$Pen^2$, D-$Pen^5$]-enkephalin increases the neuronal activity of MVN neurons via inhibition of calcium-dependent potassium currents underlying the afterhyperpolarization.

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Improvement of Fat Suppression and Artifact Reduction Using IDEAL Technique in Head and Neck MRI at 3T

  • Hong, Jin Ho;Lee, Ha Young;Kang, Young Hye;Lim, Myung Kwan;Kim, Yeo Ju;Cho, Soon Gu;Kim, Mi Young
    • Investigative Magnetic Resonance Imaging
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    • v.20 no.1
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    • pp.44-52
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    • 2016
  • Purpose: To quantitatively and qualitatively compare fat-suppressed MRI quality using iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) with that using frequency selective fat-suppression (FSFS) T2- and postcontrast T1-weighted fast spin-echo images of the head and neck at 3T. Materials and Methods: The study was approved by our Institutional Review Board. Prospective MR image analysis was performed in 36 individuals at a single-center. Axial fat suppressed T2- and postcontrast T1-weighted images with IDEAL and FSFS were compared. Visual assessment was performed by two independent readers with respect to; 1) metallic artifacts around oral cavity, 2) susceptibility artifacts around upper airway, paranasal sinus, and head-neck junction, 3) homogeneity of fat suppression, 4) image sharpness, 5) tissue contrast of pathologies and lymph nodes. The signal-to-noise ratios (SNR) for each image sequence were assessed. Results: Both IDEAL fat suppressed T2- and T1-weighted images significantly reduced artifacts around airway, paranasal sinus, and head-neck junction, and significantly improved homogeneous fat suppression in compared to those using FSFS (P < 0.05 for all). IDEAL significantly decreased artifacts around oral cavity on T2-weighted images (P < 0.05, respectively) and improved sharpness, lesion-to-tissue, and lymph node-to-tissue contrast on T1-weighted images (P < 0.05 for all). The mean SNRs were significantly improved on both T1- and T2-weighted IDEAL images (P < 0.05 for all). Conclusion: IDEAL technique improves image quality in the head and neck by reducing artifacts with homogeneous fat suppression, while maintaining a high SNR.

Design and Performance Analysis of a Communication System with AMC and MIMO Mode Selection Scheme (AMC와 MIMO 선택 기법이 결합된 통신 시스템의 설계 및 성능 분석)

  • Lee, Jeong-Hwan;Yoon, Gil-Sang;Cho, In-Sik;Seo, Chang-Woo;Portugal, Sherlie;Hwang, In-Tae
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.47 no.3
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    • pp.22-30
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    • 2010
  • This paper proposes a combination system of Adaptive Modulation and Coding (AMC) and Multiple Input Multiple Output (MIMO), which improves the throughput and has a better reliability. In addition, the system includes Precoding, Antenna Subset Selection and MIMO Mode Selection scheme. Finally, we make a performance analysis of the proposed system. The principal environmental parameters for the simulation experiment consist of a frequency non-selective rayleigh fading channel and a Spreading Factor (SF) of 16. Other parameters may be included in order to fulfill the requirements of the HSDP A Standard. The proposed system has a higher throughput and more reliability than the conventional system, which does not include MIMO Mode Selection scheme, Precoding or Antenna Subset Selection. According to the simulation results, the proposed system reaches the maximum throughput at 8dB, presentlng an improvement of 6dB and twice higher throughput, respect to the conventional system. Specifically, at the point of -6dB, the conventional system reaches 2.5Mbps, while the proposed system reaches 6.4Mbps at the same SNR. Also, at the point of 2dB, each system reaches 7.5Mbps (conventional system) and 15.3Mbps (proposed system), with near twice the difference. According to the results exposed above, we can conclude that the system proposed in this paper has, as the greatest contribution, the improvement of the throughput, especially, the average throughput.

Expression of CP4 5-Enol-Pyruvylshikimate-3- Phosphate Synthase Transgene in Inbred Line of Korean Domestic Maize (Zea may L.) (국내 옥수수 순계주에서 CP4 5-Enol- Pyruvylshikimate-3- Phosphate Synthase 유전자의 발현)

  • Cho, Mi-Ae;Kwon, Suk-Yoon;Kim, Jin-Seog;Lee, Byoung-Kyu;Moon, Choo-Yeun;Choi, Pil-Son
    • Journal of Plant Biotechnology
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    • v.34 no.4
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    • pp.375-380
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    • 2007
  • This study was conducted to develop herbicide-resistance domestic maize plants by introducing the CP4 5-enol-pyruvylshikimate-3-phosphate synthase (CP4 EPSPS) gene using Agrobacterium tumefaciens-mediated immature embryo transformation. Immature embryos of five genotypes (HW1, KL103, HW3, HW4, HW7) were co-cultivated with strains Agrobacterium tumefaciens (strain C58C1) containing the binary vector (pCAMBIA2300) carrying Ubiquitin promoter-CP4 EPSPS gene and Cauliflower mosaic virus 35S (CaMV35S) promoter-nptll gene conferring resistance to paromomycin as a selective agent. The presence and expression of CP4 EPSPS transgene were confirmed by PCR, RT-PCR and Northern blot analysis, respectively. Also, the resistance to glyphosate in the transgenic maize ($T_1$) was analyzed by shikimate accumulation assay. The frequency (%) of paromomycin-resistance callus was 0.37, 0.03, 2.20, 2.37, and 0.81% in pure lines HW1, KL103, HW3, HW4 and HW7, respectively. EPSP transgene sequences were amplified in putative transgenic plants that regenerated from paromomycin-resistance calli of two inbred lines (HW3, HW4). Of them, RT-PCR and Northern blot analyses revealed that the transgene was only expressed in two transgenic events (M266, M104) of HW4 inbred line, and a mild glyphosate resistance of transgenic event (M266) was confirmed by the lower shikimate accumulation in leaf segments. These results demonstrate that transgenic maize with herbicide-resistance traits in Korean genotype can be genetically obtained.

Fungal flora of paddy field in Korea IV. Filamentous fungi isolated by heat treatment (한국(韓國) 논토양중(土壤中)의 균류(菌類)에 관(關)한 연구(硏究) IV. 열처리(熱處理)로 분리(分離)한 사상균류(絲狀菌類))

  • Min, Kyung-Hee;Ito, Tadayoshi;Yokoyama, Tatsuo
    • The Korean Journal of Mycology
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    • v.15 no.3
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    • pp.187-195
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    • 1987
  • Two kinds of heat treatment method for the selective isolation of soil fungi to eliminate the commonest fungi and also to examine the vertical and seasonal distributions of the fungal population were applied to soil samples from two plots around Seoul area. The incubation method at $42^{\circ}C$ and heat treatment at $70^{\circ}C$ were used in this experiment. In the incubation method, the almost all the fungi isolated from two plots were mesophile, while the thermotolerant fungi was Aspergillus fumigatus and thermophilic fungi were Sporotrichum thermophile and Malbranchea pulchella var. sulfrea. The most dominant species isolated by this method was A. fumigatus. Nine genera and fourteen species were isolated from the two plots, and S. thermophile, Talaromyces ucrainicus,Malbranchea pulchella var. sulfrea were new to Korea. From the selection method by heat treatment at $70^{\circ}C$, ten genera and twenty species were isolated. Among these, the most fungi were also mesophile and thermotolerant fungus was A. fumigatus. The most dominant species isolated by this method was T. stipitatus, Talaromyces helicus var. major, Emericella nidulans var. nidulans, Chaetomium subspirale and Neosartorya fisheri var. fisheri were new to Korea. From the two isolation methods, it was found that the total number of soil fungi and frequency of species appeared including dominant ones were the highest at the soils of upper layer while the lowest at the soils of lower layer in its vertical distribution.

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Selection of Herbicide Resistant Potatoes Transformed with Phosphinothricin Acetyltransferase Gene (Phosphinothricin Acetyltransferase 유전자 도입에 의한 제초제 저항성 감자의 선발)

  • Han, S.S.;Jeong, J.H.;Bang, K.S.;Yang, D.C.
    • Korean Journal of Weed Science
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    • v.17 no.4
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    • pp.390-399
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    • 1997
  • This experiment was conducted to introduce PAT (phosphinothricin acetyltransferase, non-selective herbicide bialaphos resistant gene) gene into potato (Solanum tuberosum. cv. Desiree). Optimal shoot regeneration from leaf discs and stem segments was obtained in MS medium supplemented with 0.1 mg/L IBA and 0.5 mg/L BA, and the frequency of shoot regeneration was 54% in left discs and 46% in stem segments. In this condition, leaf discs and stem segments of potato were co-cultivated with A. tumefaciens MP90 which contained binary vector with GUS: :NPTII gene and PAT gene. Transgenic shoots were regenerated from leaf and stem-derived calli on selection medium with 100mg/L kanamycin. The 100${\mu}M$ acetosyringone treatment during the co-cultivation highly enhanced(4 times than the control) the shoot regeneration on selection medium. When the putative transgenic plants were transferred to medium with 10mg/L basta, all of them were survived. After PCR. GUS test, and Southern blot analysis of the survived plant, we confirmed that the gene was stably integrated into the potato genome and expressed. After the transgenic plants were transplanted in soil, and the transgenic plants were sprayed with the herbicide basta (300ml/10a), the transgenic plants remained green but control plants were died.

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Effects of Pine Needle Extract on Pacemaker Currents in Interstitial Cells of Cajal from the Murine Small Intestine

  • Cheong, Hyeonsook;Paudyal, Dilli Parasad;Jun, Jae Yeoul;Yeum, Cheol Ho;Yoon, Pyung Jin;Park, Chan Guk;Kim, Man Yoo;So, Insuk;Kim, Ki Whan;Choi, Seok
    • Molecules and Cells
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    • v.20 no.2
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    • pp.235-240
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    • 2005
  • Extracts of pine needles (Pinus densiflora Sieb. et Zucc.) have diverse physiological and pharmacological actions. In this study we show that pine needle extract alters pacemaker currents in interstitial cells of Cajal (ICC) by modulating ATP-sensitive $K^+$ channels and that this effect is mediated by prostaglandins. In whole cell patches at $30^{\circ}C$, ICC generated spontaneous pacemaker potentials in the current clamp mode (I = 0), and inward currents (pacemaker currents) in the voltage clamp mode at a holding potential of -70 mV. Pine needle extract hyperpolarized the membrane potential, and in voltage clamp mode decreased both the frequency and amplitude of the pacemaker currents, and increased the resting currents in the outward direction. It also inhibited the pacemaker currents in a dose-dependent manner. Because the effects of pine needle extract on pacemaker currents were the same as those of pinacidil (an ATP-sensitive $K^+$ channel opener) we tested the effect of glibenclamide (an ATP-sensitive $K^+$ channels blocker) on ICC exposed to pine needle extract. The effects of pine needle extract on pacemaker currents were blocked by glibenclamide. To see whether production of prostaglandins (PGs) is involved in the inhibitory effect of pine needle extract on pacemaker currents, we tested the effects of naproxen, a non-selective cyclooxygenase (COX-1 and COX-2) inhibitor, and AH6809, a prostaglandin EP1 and EP2 receptor antagonist. Naproxen and AH6809 blocked the inhibitory effects of pine needle extract on ICC. These results indicate that pine needle extract inhibits the pacemaker currents of ICC by activating ATP-sensitive $K^+$ channels via the production of PGs.

Married Woman's Family Life Management Behavior - Consumer's Purchase Behavior, Dietary Life Behavior, and Satisfaction of Well-Being Oriented Food - (기혼여성의 가정생활관리행동: 웰빙지향 식품 구매행동 및 식생활 행동과 소비만족도)

  • Han, Sung-Hee
    • Journal of Family Resource Management and Policy Review
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    • v.14 no.2
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    • pp.127-152
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    • 2010
  • This study examined the satisfaction of the married women from aged 20s through 50s with well-being oriented foods, considering the importance of each subordinate field and verifying the differences between the groups according to socio-demographic factors, purchase behavior factors, and well-being oriented dietary life factors, followed by an analysis of the relative influence of those relevant factors. A preliminary survey was conducted from January 4th-11th, 2009 to check if there were any problems or misunderstood parts before the main survey. After the preliminary study was conducted, certain problems were adjusted and supplemented, and then the main survey was conducted for twenty-three days, from January 4th to February 5th, 2009. The summaries of this study are as follows: First, in the view of the purchase behavior, the mainly purchased well-being oriented foods were farm products, and the leading purpose of the purchase was for the parents and the children. It was shown that 30% or more of the information sources on well-being oriented foods were families, relatives and neighbors. More than 66% of the purchasing was done at wholesale marts and the topped purchasing frequency was from 5 to 6 per month. More than 71% of payments for well-being oriented foods were \50,000~100,000 per month. More than 51% of the respondents answered that the proper price of well-being oriented foods was 1.2 times to 1.5 times of that of other foods. Second, the satisfaction of the well-being oriented foods was ranked as 3.21 to 3.28 out of 5, and varied with the usages and the methods of weights. Investigating the satisfaction with each subordinate field, the satisfaction with price was shown to be low. The satisfaction with the assortments of foods and the satisfaction with the therapeutic degree by thorough investigation and management of foods were also relatively low. Third, well-being oriented dietary behavior was shown to be characterized by two factors, through factor analysis in this study. One was an eco-friendly oriented behavioral factor and the other was a health oriented selective factor. Fourth, the stepwise multiple regression analysis results investigating the relative influence of the factors effecting satisfaction with well-being oriented foods showed that the top ranked factor affecting total satisfaction was eco-friendly oriented behavioral factor, followed by education level and purchasing sites, especially of consumer groups.

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Cell fusion and fusants characterization of Bacillus strains producing biopolymer (Biopolymer 생산성 Bacillus 속 균주의 세포융합과 융합주의 세포특성)

  • Yim, Moo-Hyun;Kim, Seong-Ho
    • Applied Biological Chemistry
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    • v.42 no.1
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    • pp.12-19
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    • 1999
  • To improve biopolymer productivity and properties of Bacillus strains, protoplast fusion was performed between biopolymer producing Bacillus subtilis K-1 and lactose utilizing Bacillus coagulans. The results were as follows; Protoplasts mixed in fusion fluid containing 33% PEG 6000, 1% PVP and 10 mM $CaCl_2$ were reacted for 5 min at $37^{\circ}C$ and then centrifused protoplasts were directly overlaid on the selective media containing $100\;{\mu}g/ml$ antibiotics and incubated for 3 days. At this conditions, the frequency of protoplast fusion was generally in the range of $4.6{\times}10^{-5}\;to\;1.8{\times}10^{-7}$ in ratio. Segregation ratio was observed between 1 to 6% indicating genetic stability of all the fusants. Fusants growth were also observed on the media contained amino acid and antibiotics as required marked materials. DNA contents of the selected fusants were 1.6 to 2.7 times more than that of parent strains. With observation by TEM microscopy, spherical protoplasts were first released from the swollen parental cells and then contracted to fuse in the process of fusion. And fused cells were observed representative vesicle. Originally, the parental cells were observed as in the morphology of thick-walled and double membrane-surrounded rod shape with TEM microscopy.

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A Study on the Propagation Environment for VHF Maritime Digital Communications Operation in South Sea Area (남해안의 VHF 해상디지털통신 운용을 위한 전파환경 연구)

  • Ju, Yang-Ro;Kim, Kab-Ki;Choi, Jo-Cheon;Lee, Seong-Ro
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.6
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    • pp.1310-1316
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    • 2014
  • The IMO has recommended on VHF digital communications operation for sailing ships from 2017. And ships more than 5 tons is obliged to digital communications by fishing Vessels Act and Vessel Safety Act in domestic. The owner of all vessel is equipped to the automatic position reporting device in accordance with the Notice of the Ministry of Oceans and Fisheries to regulations, It shall be ensure to navigations safety and in order to respond quickly in the event of maritime accidents on all vessels. The info-communications station of fishery is operating the automatic position reporting system using the VHF DSC in east sea from 2012, Continuously, which is underway the install plan in south sea and yellow sea. But this plan is very difficult, because of propagation environment is poor on account of complicated coastline and many islands. This paper has analyzed the propagation coverage for position setting of coast station in south sea and the traffic zone set up by compare with RSSI and methode of navigation tracking by VMS.