• Title/Summary/Keyword: amplitude difference

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The Diurnal Change of Accommodative Functions by Near Work (일과 중 근거리 작업에 따른 조절기능의 변화)

  • Lee, Jeong-Yun;Yu, Dong-Sik;Son, Jeong-Sik;Cho, Hyun Gug;Moon, Byeong-Yeon
    • Journal of Korean Ophthalmic Optics Society
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    • v.16 no.1
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    • pp.75-81
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    • 2011
  • Purpose: The daily changes of accommodation at period 1 (08:00~10:00), period 2 (13:00~15:00) and period 3 (18:00~20:00) were surveyed with fifty two incipient presbyopia of from 38 to 49 years old. Methods: 52 incipient presbyopia subjects (30 men, 22 women) were classified into 4 groups (groupI: ${\geq}$ 7 hrs~group IV: < 3 hrs) according to near working amount. Their amplitude of accommodation, accommodative facility and relative amplitude of accommodation were inspected, respectively. Results: The amplitude of accommodation was measured to be the lowest for the groupI that near working time was the most during daily work, and the amplitude of accommodation of oculus dexter, oculus sinister and oculus uterque were the highest at period 2 in case of all the group I~IV. In the accommodative facility, it appeared that the oculus dexter, oculus sinister and oculus uterque of group I, oculus dexter and oculus sinister of group II, and oculus dexter, oculus sinister and oculus uterque of group III were the highest at period 2. The oculus uterque of group II and oculus dexter, oculus sinister and oculus uterque of group IV were the highest accommodative facility at period 3. It appeared that the negative relative accommodation was the highest at period 1 in case of all the group I~IV, and the positive relative accommodation was the highest at period 2 in case of the group I~III and was the highest at period 3 in case of the group IV. Conclusions: Because the difference of near working time affects the accommodation, it would become a help in solving the asthenopia symptom of the incipient presbyopia that opticians consider their near working time during daily work and take a checkup on their accommodation.

A Study on Implemetation of Non-invasive Blood Pressure (비침습적 혈압 측정 시스템 구현에 관한 연구)

  • 노영아;이종수;김영길
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2000.10a
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    • pp.451-454
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    • 2000
  • Invasive methode and Non-invasive methode are used in blood pressure measurement. The Invasive methode can Set the correct measured blood pressure but, it has patient feels uncomfortable. So most of cases use Non-invasive methode. The Oscillometric method is commonly apply to modem electric sphygmomanometer and using various algorithm. In this paper describe about a algorithm it control and to determinate the cuff pressure, and filtering that data for measure the blood pressure. The communicating with personal computer can pressure deflation is by Solenoid valve and it uses RS-232 system in packet communication. The main using algorithm for blood pressure measurements are maximum amplitude algorithm and oscillometric algorithm. MAA(maximum amplitude algorithm) has various measured oscillation it depend on patient's age, height, weight and arm circumference size. In this paper, 1 studied the various measured oscillation apply to characteristic ratio and can get the result of systolic blood pressure, diastolic blood pressure, mean blood pressure. It was not used same ratio to measuring oscillation. In the MAA(maximum amplitude algorithm), we hope for reduce the difference with the real blood pressure and the measured blood pressure, when it applied with various specific ratio.

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P3 in the Auditory Event-Related Evoked Potential of Schizophrenia(I) -P3 in the Schizophrenics- (정신분열증의 사건관련유발전위에 대한 연구(I) -정신분열증 환자의 사건관련유발전위-)

  • Oh, Dong-Jae;Chang, Hwan-Il
    • Sleep Medicine and Psychophysiology
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    • v.1 no.1
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    • pp.87-98
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    • 1994
  • Objectives: To examine a defect in inhibitory gating of auditory evoked response in schizophrenics, to compare P3 latency and amplitude in negative and positive schizophrenics, and to assess the association of P3 with family history of the psychiatric disorders, electroconvulsive therapy, and clinical features. Methods: 54 schizophrenics(male 31, female 23) and 75 controls(male 33, female 42) were tested with event-related potential paradigm designed to elicit P3 response and Frankfurter Beschwerde Fragebogen. Results: In schizophrenics, the latency of P3 was significantly more delayed and the amplitude of P3 was significantly more reduced than in the controls. Significant differences in P3 latency and amplitude between negative and positive schizophrenics were not found. And significant difference in the P3 latency and amplitude between schizophrenics with family histories of psychiatric disorder and those without family histories of psychiatric disorder was not found also. The P3 latency and amplitude was not significantly related with electroconvulsive therapy and other clinical features such as age, duration of illness, onset of inllness, number of admission, and doses of antipsychotics etc. Conclusion: These results suggested that schizophrenics had a dysfunction in the process of selective attention and that P3 was not significantly related with family history of the psychiatric disorders, positive and negative symptoms, electro1convulsive therapy, and clinical features in schizophrenics.

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A Linear Wave Equation Over Mild-Sloped Bed from Double Integration (이중적분을 이용한 완경사면에서의 선형파 방정식)

  • Kim, Hyo-Seob;Jung, Byung-Soon;Lee, Ye-Won
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.12 no.3
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    • pp.165-172
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    • 2009
  • A set of equations for description of transformation of harmonic waves is proposed here. Velocity potential function and separation of variables are introduced for the derivation. The continuity equation is in a vertical plane is integrated through the water so that a horizontal one-dimensional wave equation is produced. The new equation composed of the complex velocity potential function, further be modified into. A set up of equations composed of the wave amplitude and wave phase gradient. The horizontally one-dimensional equations on the wave amplitude and wave phase gradient are the first and second-order ordinary differential equations. They are solved in a one-way marching manner starting from a side where boundary values are supplied, i.e. the wave amplitude, the wave amplitude gradient, and the wave phase gradient. Simple spatially-centered finite difference schemes are adopted for the present set of equations. The equations set is applied to three test cases, Booij's inclined plane slope profile, Massel's smooth bed profile, and Bragg's wavy bed profile. The present equations set is satisfactorily verified against existing theories including Massel's modified mild-slope equation, Berkhoff's mild-slope equation, and the full linear equation.

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The Affective Influences on Perceptual Load Effect: An Event-related Potential Study (지각부담효과에 미치는 정서의 영향: ERP 연구)

  • Park, Tae-Jin;Kim, Jung-Hee
    • Korean Journal of Cognitive Science
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    • v.23 no.2
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    • pp.165-184
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    • 2012
  • To investigate how the valence of unattended background picture modulates perceptual processing of a target letter, participants were required to detect a target letter among six letters superimposed on an IAPS picture. Perceptual load was manipulated by varying the difficulty of letter detection, and behavioral results showed more accurate and faster detection responses at the low-load condition than at the high-load condition. The analysis of ERP data of control condition at which six letters were presented without an IAPS picture showed perceptual load effects on mean amplitude of N1 and P1 ERP components. At experimental condition including an IAPS picture, interaction between valence and perceptual load was observed on mean amplitude of N1 at posterior visual processing area, and the amplitude difference between low-load condition and high-load condition was larger on a negative background picture than on a neutral background picture. The results suggest that more attentional capacity might be consumed by a negative picture than by a neutral picture, and suggest that unattended affective picture is processed automatically and influence the early perceptual processing of target stimulus.

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Changes in Nerve Excitability During Neural Stretching (신경 신장 적용 시간에 따른 신경흥분성 변화)

  • Lee, Dong-Rour;Rhee, Min-Hyung;Eom, Ju-Ri;Kim, Jong-Soon
    • PNF and Movement
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    • v.16 no.2
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    • pp.287-294
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    • 2018
  • Purpose: The neurodynamic test used to implicate symptoms arising from the nerve is proposed to selectively increase the strain of the nerve without increasing the strain of adjacent tissue, although this has not yet been established in the time of nerve tension application. This study aimed to investigate the acute effects of nerve stretching time on nerve excitability using compound nerve action potential (CNAP) analysis. Methods: Thirty healthy young adults (mean age=23.10 years) with no medical history of neurological or musculoskeletal disorder voluntarily participated in this study. Nerve excitability was assessed using the median nerve conduction velocity test. The amplitude of the CNAP was measured under three conditions: resting phase (supra-maximal stimulus, without nerve stretching), baseline phase (two-thirds of the supra-maximal stimulus, without nerve stretching), and stretch phase (two-thirds of the supra-maximal stimulus, with 1-5 minutes nerve stretching). One-way repeated measures ANOVA was conducted to compare the latency and amplitude of CNAP. A post-hoc test was analyzed using the contrast test. Results: The latency was significantly delayed after 1 min. of nerve stretching in comparison with the baseline test. However, no significant difference was found during the nerve stretching (1-5 min.). The amplitude was significantly increased by nerve stretching. Conclusion: Nerve stretching can induce nerve excitability without any nerve injury. Based on the results, more than 1 min. of nerve stretching as a neurodynamic test can be a useful method in the clinical setting.

Antidromic Electrically Compound Action Potential in Cochlear Implantees (인공와우 이식자의 역행성 청신경 복합활동전위)

  • Heo, Seung-Deok;Jung, Sung-Wook;Jung, Seung-Hyun
    • Phonetics and Speech Sciences
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    • v.1 no.4
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    • pp.203-207
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    • 2009
  • Electrically evoked compound action potentials (ECAP) have originated from the distal end of the auditory nerve. ECAP are characterized as the difference between the clearly large trough (N) and the following positive peak (P). N-wave occurs around $200-400\;{\mu}s$ after stimulus onset and P-wave at around $400-800\;{\mu}s$. Contrary to expectations, positive peaked ECAP (pp-ECAP) was dominated by a relatively large-amplitude positive following negative peak. pp-ECAP can be recorded from the sites on or near the surgically exposed nerve trunk in animal models and/or in cases of monophasic stimulation. This study will provide the causes of the appearance of pp-ECAP in cases of cochlear implant recipients using imaging studies and medical records and statistically analysis between N-P and P-N on the amplitude input-output function (amp-I/O) for the prediction of the possibilities of clinical tools. Thirteen children participated in the study and received a Cochlear CI-24RE (CA). ECAP was recorded using auto-NRT (Cochlear Ltd., Australia) at four to five weeks post surgery. pp-ECAP was measured from 36 electrodes and typical ECAP from 220 electrodes. There was no abnormality in the imaging study and operation finding in patients with typical ECAP. pp-ECAP was found at the inner ear anormaly and ossification in imaging study and gel-state inner ear fluid was observed in the operation finding. The amplitude of pp-ECAP increased depending on current intensities, but amp-I/O increase more gradually than in the case of typical ECAP (p=0.003). pp-ECAP is antidromic potential which can record from the inner ear anormaly and ossified cochlear. Amp-I/O also depends on current intensity as well typical ECAP. These results provide a useful tool for audiological evaluation for the spiral ganglion cell status to the value of pp-ECAP.

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SgrA* 22GHz KaVA(+TAK) observation and its Amplitude Calibration

  • CHO, ILJE;JUNG, TAEHYUN;ZHAO, GUANG-YAO;KINO, MOTOKI;SOHN, BONGWON
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.2
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    • pp.52.2-52.2
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    • 2015
  • SgrA* located in the center of the Milky Way is of great interest to understand the physics of supermassive black hole(SMBH) and the interaction of the G2 cloud around SgrA* with the accretion flow which was expected since 2013. In order to seize this rare opportunity, KVN and VERA Array (so called, KaVA) has started an intensive monitoring program of SgrA* at 22/43 GHz where scatter broadening is reduced compared to lower frequency VLBI observations. We present the results of KaVA SgrA* observation together with Takahagi (32m) and Yamaguchi (32m) telescopes at 22 GHz on March 24, 2013. We have tested both a standard amplitude calibration methods using the Tsys and antenna gain information and a template amplitude calibration method which uses a peak of H2O maser line of nearby maser source (SgrB2), and found that the latter method is useful when an accuracy of Tsys measurement or antenna gain of a telescope is poor. In our comparison, the difference between the two methods is around 20% (~5% for the KVN and ~15% for the VERA when the elevation is above $20^{\circ}$). We also imaged SgrA* with a total flux of ~0.7 Jy at 22GHz, and fitted an elliptical Gaussian model which has a size of ~2.5mas for major axis and ~1.7mas for minor axis, respectively.

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Time course of the denervation in early stage of Bell's palsy.: Identification by electrophysiologic study (초기 벨마비에서 나타나는 탈신경의 시간경과에 따른 변화: 전기생리학적 검사를 통한 확인)

  • Bae, Jong-Seok;Uhm, Keun-Yong;Kim, Byoung-Joon;Kwon, Ki-Han
    • Annals of Clinical Neurophysiology
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    • v.6 no.1
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    • pp.26-30
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    • 2004
  • Background: Electrophysiologic study accurately predicts the degree of degenerated motor axons but cannot give precise information on the type of injury that occurred in Bell's palsy. Because of these limitation for prognostic prediction in Bell's palsy, we evaluated divergence of electrophysiological time course for the purpose of presuming the type of injury in Bell's palsy. Methods: We did bilateral facial nerve conduction studies in 103 Bell's palsy patients, who visited to Han-Gang sacred heart hospital from 1998 to 2001. We compared the CMAP amplitude of disease site with that of normal site and suggested that decremental CMAP amplitude ratio (percentage) as a degree of denervation of affected facial nerve. Then we demonstrated the time course of denervation percentage. After defining normal range of CMAP amplitude difference from normal control group, we also evaluated if distinct time course of early minimal denervation is present. Results: Our results show that time course of the denervation in early stage of Bell's palsy reflect various injury type such as axonotmesis, neurotmesis or other unidentified type. We cannot identify the distinct time course of early minimal denervation. Conclusions: The time course as well as the maximal value of denervation are the best prognostic guidelines in Bell' s palsy. So repeated serial electrophysiologic test are inevitable to assess prognosis. As an another topic, early minimal denervation for prognostic prediction deserve to be evaluated as a future work up for prognostic prediction.

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Higher Expression of TRPM7 Channels in Murine Mature B Lymphocytes than Immature Cells

  • Kim, Jin-Kyoung;Ko, Jae-Hong;Nam, Joo-Hyun;Woo, Ji-Eun;Min, Kyeong-Min;Earm, Yung-E;Kim, Sung-Joon
    • The Korean Journal of Physiology and Pharmacology
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    • v.9 no.2
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    • pp.69-75
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    • 2005
  • TRPM7, a cation channel protein permeable to various metal ions such as $Mg^{2+}$, is ubiquitously expressed in variety of cells including lymphocytes. The activity of TRPM7 is tightly regulated by intracellular $Mg^{2+}$, thus named $Mg^{2+}$-inhibited cation (MIC) current, and its expression is known to be critical for the viability and proliferation of B lymphocytes. In this study, the level of MIC current was compared between immature (WEHI-231) and mature (Bal-17) B lymphocytes. In both cell types, an intracellular dialysis with $Mg^{2+}$-free solution (140 mM CsCl) induced an outwardly-rectifying MIC current. The peak amplitude of MIC current and the permeability to divalent cation ($Mn^{2+}$) were several fold higher in Bal-17 than WEHI-231. Also, the level of mRNAs for TRPM7, a molecular correspondence of the MIC channel, was significantly higher in Bal-17 cells. The amplitude of MIC was further increased, and the relation between current and voltage became linear under divalent cation-free conditions, demonstrating typical properties of the TRPM7. The stimulation of B cell receptors (BCR) by ligation with antibodies did not change the amplitude of MIC current. Also, increase of extracellular $[Mg^{2+}]_c$ to enhance the $Mg^{2+}$ influx did not affect the BCR ligation-induced death of WEHI-231 cells. Although the level of TRPM7 was not directly related with the cell death of immature B cells, the remarkable difference of TRPM7 might indicate a fundamental change in the permeability to divalent cations during the development of B cells.