• Title/Summary/Keyword: Normal polarity

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Simultaneous Chiral Discrimination of Nine Non-Steroidal Antiinflammatory Drugs by Cyclodextrin-Modified Capillary Electrophoresis in Normal and Reversed Polarity Modes

  • Kim, Ji-Yung;La, Sook-Ie;Kim, Jung-Han;Kim, Kyoung-Rae
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.276.2-276.2
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    • 2003
  • Simultaneous enantioseparation of nine racemic non-steroidal antiinflammatory drugs (NSAIDs) for their accurate chiral discrimination was achieved by cyclodextrin (CO) modified capillary electrophoresis in the normal polarity (NP) mode and in the reversed polarity (RP) mode. The NP mode employed neutral tri-O-methyl-${\beta}$-cyclodextrin (TM${\beta}$CD) as a selector dissolved in MES buffer (PH 6.0). (omitted)

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Influence of Stimulus Polarity on the Auditory Brainstem Response From Level-Specific Chirp

  • Dzulkarnain, Ahmad Aidil Arafat;Salamat, Sabrina;Shahrudin, Fatin Amira;Jamal, Fatin Nabilah;Zakaria, Mohd Normani
    • Journal of Audiology & Otology
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    • v.25 no.4
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    • pp.199-208
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    • 2021
  • Background and Objectives: No known studies have investigated the influence of stimulus polarity on the Auditory Brainstem Response (ABR) elicited from level-specific (LS) chirp. This study is important as it provides a better understanding of the stimulus polarity selection for ABR elicited from LS chirp stimulus. We explored the influence of stimulus polarity on the ABR from LS chirp compared to the ABR from click at 80 dBnHL in normal-hearing adults. Subjects and Methods: Nineteen adults with normal hearing participated. The ABRs were acquired using click and LS chirp stimuli using three stimulus polarities (rarefaction, condensation, and alternating) at 80 dBnHL. The ABRs were tested only on the right ear at a stimulus rate of 33.33 Hz. The ABR test was stopped when the recording reached the residual noise level of 0.04 μV. The ABRs amplitudes, absolute latencies, inter-peak latencies (IPLs), and the recorded number of averages were statistically compared among ABRs at different stimulus polarities and stimuli combinations. Results: Rarefaction polarity had the largest ABR amplitudes and SNRs compared with other stimulus polarities in both stimuli. There were marginal differences in the absolute latencies and IPLs among stimulus polarities. No significant difference in the number of averages required to reach the stopping criteria was found. Conclusions: Stimulus polarities have a significant influence on the ABR to LS chirp. Rarefaction polarity is recommended for clinical use because of its larger ABR peak I, III, and V amplitudes than those of the other stimulus polarities.

Influence of Stimulus Polarity on the Auditory Brainstem Response From Level-Specific Chirp

  • Dzulkarnain, Ahmad Aidil Arafat;Salamat, Sabrina;Shahrudin, Fatin Amira;Jamal, Fatin Nabilah;Zakaria, Mohd Normani
    • Korean Journal of Audiology
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    • v.25 no.4
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    • pp.199-208
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    • 2021
  • Background and Objectives: No known studies have investigated the influence of stimulus polarity on the Auditory Brainstem Response (ABR) elicited from level-specific (LS) chirp. This study is important as it provides a better understanding of the stimulus polarity selection for ABR elicited from LS chirp stimulus. We explored the influence of stimulus polarity on the ABR from LS chirp compared to the ABR from click at 80 dBnHL in normal-hearing adults. Subjects and Methods: Nineteen adults with normal hearing participated. The ABRs were acquired using click and LS chirp stimuli using three stimulus polarities (rarefaction, condensation, and alternating) at 80 dBnHL. The ABRs were tested only on the right ear at a stimulus rate of 33.33 Hz. The ABR test was stopped when the recording reached the residual noise level of 0.04 μV. The ABRs amplitudes, absolute latencies, inter-peak latencies (IPLs), and the recorded number of averages were statistically compared among ABRs at different stimulus polarities and stimuli combinations. Results: Rarefaction polarity had the largest ABR amplitudes and SNRs compared with other stimulus polarities in both stimuli. There were marginal differences in the absolute latencies and IPLs among stimulus polarities. No significant difference in the number of averages required to reach the stopping criteria was found. Conclusions: Stimulus polarities have a significant influence on the ABR to LS chirp. Rarefaction polarity is recommended for clinical use because of its larger ABR peak I, III, and V amplitudes than those of the other stimulus polarities.

Linear Solvation Energy Comparison Study in Normal Phase Liquid Chromatography Ⅰ (정상 액체크로마토그래피에서의 선형 용매화에너지 비교법 연구 Ⅰ)

  • Choe, Jang Deok;Jeong, Won Jo
    • Journal of the Korean Chemical Society
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    • v.38 no.3
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    • pp.221-223
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    • 1994
  • We tried to apply the linear solvation energy comparison method to solute retention in normal phase liquid chromatography. Correlation coefficients of regression of lnk' collected in a fixed eluent against solute polarity indices have proven to be lower than those obtained from reversed phase liquid chromatography data. This event can be attributed to complexity of solute retention process in normal phase liquid chromatography. We concluded from the regression results that each specific polarity of the stationary phase is greater than that of the mobile phase and that the difference in each polarity between the stationary phase and the mobile phase decreases as the volume fraction(${\phi}$) of the more polar solvent in the mobile phase increases. Correlations of lnk' of a single solute against solvent polarity indices have proven to be meaningless owing to covariance among the solvent polarity indices. Instead, a good linear relationship between lnk' and solvent ${\pi}^*$ was observed, and its linearity is better than that between lnk' and ${\phi}$.

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Function of rax2p in the Polarized Growth of Fission Yeast

  • Choi, Eunsuk;Lee, Kyunghee;Song, Kiwon
    • Molecules and Cells
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    • v.22 no.2
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    • pp.146-153
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    • 2006
  • Cell polarity is critical for the division, differentiation, migration, and signaling of eukaryotic cells. RAX2 of budding yeast encodes a membrane protein localized at the cell cortex that helps maintain the polarity of the bipolar pattern. Here, we designate SPAC6f6.06c as $rax2^+$ of Schizosaccharomyces pombe, based on its sequence homology with RAX2, and examine its function in cell polarity. S. pombe $rax2^+$ is not essential, but ${\Delta}rax2$ cells are slightly smaller and grow slower than wild type cells. During vegetative growth or arrest at G1 by mutation of cdc10, deletion of $rax2^+$ increases the number of cells failing old end growth just after division. In addition, this failure of old end growth is dramatically increased in ${\Delta}tea1{\Delta}rax2$, pointing to genetic interaction of $rax2^+$ with $tea1^+$. ${\Delta}rax2$ cells contain normal actin and microtubule cytoskeletons, but lack actin cables, and the polarity factor for3p is not properly localized at the growing tip. In ${\Delta}rax2$ cells, and endogenous rax2p is localized at the cell cortex of growing cell tips in an actin- and microtubule-dependent manner. However, ${\Delta}rax2$ cells show no defects in cell polarity during shmoo formation and conjugation. Taken together, these observations suggest that rax2p controls the cell polarity of fission yeast during vegetative growth by regulating for3p localization.

A study on how to discriminate the polarities of stator windings for 3 phase induction motors by using induced voltages based on residual magnetism (잔류자기 유도 기전력을 이용한 3상유도전동기 권선의 극성 판별법에 관한 연구)

  • Choi, Soon-Man
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.9
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    • pp.1146-1149
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    • 2014
  • To discriminate polarities of stator windings for 3 phase induction motors terminal tags of which are not readable, it is possible to utilize the residual magnetic flux present at their rotors as well as to use the way based on external exciting current. The induced voltages are basically decided by parameters such as the quantity of residual flux, the rotator speed by hand force and the phase properties between stator windings. To adopt induced voltages by residual flux for polarity discrimination at sites, the measured voltages by multi-testers need to be readable in magnitude enough to discriminate winding condition with reasonable phase characteristics. This study focuses on the analysis of various connection cases in the expectation that the summing voltages induced by residual flux shall show zero in case of normal connections while the sum becomes greater indication if the connection is in wrong condition. The proposed method is applied to actual motors to disclose how effective it is for polarity discrimination at sites through comparison of output signals between normal and fault connections.

The Study of Formation for Dokdo Seamounts at the Northeastern Part of the Ulleung Basin Using Gravity and Magnetic Data (중력 및 자력자료 분석에 의한 울릉분지 북동부 독도 및 주변 해산들의 형성 연구)

  • Kim, Chang-Hwan;Park, Chan-Hong;Ko, Young-Tak;Jung, Eui-Young;Kwak, Jun-Young;Yoo, Sang-Hoon;Min, Kyung-Duck
    • Economic and Environmental Geology
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    • v.40 no.2 s.183
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    • pp.153-170
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    • 2007
  • Loading time and loading environment of the Dokdo seamounts were studied from flexure model and VGP(Virtual Geomagnetic Pole) determined by gravity and magnetic data. In spite of their similarity in size. a large difference about 50 mGal between gravity anomaly peaks of Dokdo and the Isabu Tablemount suggests different compensation degrees. Flexural modeling results show that the flexural rigidity(effective elastic thickness) of lithosphere for Dokdo is stronger(thicker) than that for the Isabu Tablemount. Also, it implies that the age of lithosphere at the time of loading of the Isabu Tablemount may be younger than that of Dokdo. Magnetic anomalies occur complicated over the Dokdo seamounts. Paleomagnetism was studied from VGP estimated by the least square and the seminorm magnetization methods with 1500 m upward continued magnetic anomalies. Age dating of Dokdo from previous study, flexural modeling, VGP, and geomagnetic polarity time scale suggest that after the cease of spreading in the Ulleung Basin, the Isabu Tablemount was formed first in normal polarity interval and followed by Dokdo. Also, they indicate that the fist large eruption of Dokdo was in normal polarity interval and the second large eruption in reversed polarity interval. The Simheungtaek Tablemount was formed in normal polarity interval between the formations of the Isabu Tablemount and Dokdo. These loading times for the Dokdo seamounts show a good coherence with the compressive stress period after the end of the opening of the East Sea. The Dokdo seamounts probably was caused by volcanism associated with the compressive stress.

Current Limiting Characteristics of a Flux-Lock Type SFCL for a Single-Line-to-Ground Fault

  • Oh, Geum-Kon;Jun, Hyung-Seok;Lee, Na-Young;Choi, Hyo-Sang;Nam, Gueng-Hyun
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.20 no.9
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    • pp.70-77
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    • 2006
  • We have fabricated an integrated three-phase flux-lock type SFCL, which consists of an YBCO($YB_a2Cu_3O_7$) thin film and a flux-lock reactor wound around an iron core of each phase. In order to apply the SFCL in a real power system, fault analyses for the three-phase system are essential. The short-circuit currents were effectively limited by adjusting the numbers of winding of each secondary coil and their winding directions. The flux flow generated in the iron core cancelled out under the normal operation due to the parallel connection between primary and secondary windings. However, the flux-lock type SFCL with same iron core was operated just after the fault due to the flux generating in the iron core. To analyze the current limiting characteristics, the additive polarity winding was compared with the subtractive one in the flux lock reactor. Whenever a single line-to-ground fault occurred in any phase, the peak value of the line current of the fault phase in the additive polarity winding increased up to about 12.87 times during the first-half cycle. On the other hand, the peak value in the subtractive polarity winding increased up to about 34.07 times under the same conditions. This is because the current flow between the primary and the secondary windings changed to additive or subtractive status according to the winding direction. We confirmed that the current limiting behavior in the additive polarity winding was more effective for a single-line-to-ground fault

Interaction of Nonreceptor Tyrosine-Kinase Fer and p120 Catenin Is Involved in Neuronal Polarization

  • Lee, Seung-Hye
    • Molecules and Cells
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    • v.20 no.2
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    • pp.256-262
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    • 2005
  • The neuronal cytoskeleton is essential for establishment of neuronal polarity, but mechanisms controlling generation of polarity in the cytoskeleton are poorly understood. The nonreceptor tyrosine kinase, Fer, has been shown to bind to microtubules and to interact with several actin-regulatory proteins. Furthermore, Fer binds p120 catenin and has been shown to regulate cadherin function by modulating cadherin-${\beta}$-catenin interaction. Here we show involvement of Fer in neuronal polarization and neurite development. Fer is concentrated in growth cones together with cadherin, ${\beta}$-catenin, and cortactin in stage 2 hippocampal neurons. Inhibition of Fer-p120 catenin interaction with a cell-permeable inhibitory peptide (FerP) increases neurite branching. In addition, the peptide significantly delays conversion of one of several dendrites into an axon in early stage hippocampal neurons. FerP-treated growth cones also exhibit modified localization of the microtubule and actin cytoskeleton. Together, this indicates that the Fer-p120 interaction is required for normal neuronal polarization and neurite development.

A Study of the Classification of Different Types of the Golgi Apparatus around the Bile Canaliculus in the Rat Liver (담세관주위 Golgi장치의 유형 분류에 관한 전자현미경적 연구)

  • Chung, Min-Hwa;Shin, Young-Chul
    • Applied Microscopy
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    • v.22 no.2
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    • pp.46-65
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    • 1992
  • In this study, we have made morphological and cytochemical observations to investigate the type of Golgi apparatus around the bile canaliculus. The animal (Wister, $220{\sim}250gm$) were divided into 4 groups; normal, hydrochol, colchicine and hydrochol-colchicine. The Golgi apparatus is classified into 16 different types from 4 different groups. In the normal group, we could observe 12 different types of the sixteen. Type I which showed convexed cisterns facing the bile canaliculi was most abundant of the types. In the hydrochol group, 14 types were observed. Type VII and type I showed convexed cisterns facing the bile canaliculus and were abundant. In the colchicine group, 11 different types were viewed and type XIV which showed intensely dilated cisterns without the polarity was predominant. In the hydrochol-colchicine group, we observed 3 different types. Type XIV clearly showed the highest percentage, although that type was less numerous in this group than in the colchicine group. In the hydrochol group, the Golgi apparatus showed a tendency to increase in numbers, while in the hydrochol-colchicine group the Golgi apparatus showed a tendency to decrease in numbers. The reactive products of thiamine pyrophosphatase and acid phosphatase were apparent over the distal Golgi cistern in the normal and hydrochol groups, but were decreased or not observed in the colchicine and hydrochol-colchicine groups. From the results, it is assumed that with the presence of the microtubule, Golgi cisterns are dilated with polarity after stimulation of secretion. Without the microtubule, the cistern becomes more intensely dilated and none polaric. Also the enzymes within the cisternal membrane become decreaed or absent and the Golgi apparatus decreases in numbers after activation of secretion.

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