• Title/Summary/Keyword: polygraph

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The Study of EEG Signal Display as a Multirate Sampling Problem (멀티레이터 샘플링 문제로서의 뇌파신호 디스플레이에 관한 연구)

  • 최한고
    • Journal of Biomedical Engineering Research
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    • v.17 no.2
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    • pp.209-214
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    • 1996
  • The display of biological signals in raster scan monitors often involves a multirate sampling operation which consists of decimation .and interpolation. All electroencephalouaphic (EEG) samples of 10 to 30 seconds (2, 500 to 7, 500 samples at 250[Hz] sampling frequency) must be displayed in the computer screen to keep the aspect ratio of the paper polygraph output. Since the current afrorclable display technology Plots at most 2, 000 Pixels Per row, sDme signal samples need to be discarde4 This Paper studies methods to perform this operation characterizing them from the signal processing viewpoint and compares the display quality among several decimation techniques. Experimental results show that a nonlinear operation such as the peak detection method could be preferable to the canonical linear filtering to reduce aliasing.

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Relaxation of P2-purinoceptor on isolated renal artery of rabbit (토끼 적출 신동맥에 있어서 P2-purinoceptor의 이완작용)

  • Kim, Joo-heon;Kim, Yong-keun
    • Korean Journal of Veterinary Research
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    • v.32 no.1
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    • pp.7-13
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    • 1992
  • To elucidate the action of $P_2$-purinoceptor, effects of adenosine triphosphate(ATP) and perivascular nerve stimulation were investigated from polygraph in the isolated renal artery of rabbit 1. ATP caused the relaxation on the precontraction with noradrenaline$(10{\mu}M)$ on the presene and absence of endothelium in the isolated renal artery of rabbit, the relaxative response was increased between 0.1 and $30{\mu}M$ on dose-dependent manner. 2. The relaxative response induced by ATP$(10{\mu}M)$ on precontraction with noradrenaline$(10{\mu}M)$ was blocked by the pretreatment with reactive blue 2$(10{\mu}M)$. 3. ATP inhibited the contractile response by perivascular nerve stimulation(0.3ms, 80V, 50Hz, 1 sec), the inhibitory action was blocked by the pretreatment with 8-phenyltheophylline$(10{\mu}M)$.

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EEG signal display as a multirate sampling problem (멀티레이터 샘플링 문제로서의 뇌파신호 디스플레이)

  • Choi, H.G.;Oh, Y.S.;Lee, S.J.
    • Proceedings of the KOSOMBE Conference
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    • v.1996 no.05
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    • pp.311-314
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    • 1996
  • The display of biological signals in monitors often involves a multirate sampling operation which consists of decimation and intenolation. All electroencephalographic (EEG) samples of 10 to 30 seconds must be displayed in the computer screen to keep the aspect ratio of the paper polygraph output. Since the current affordable display technology plots at most 2,000 pixels per row, some samples need to be discarded. This paper studies methods to perform this operation characterizing them from the signal processing viewpoint and compares the display quality among several decimations. Experimental results show that a nonlinear operation such as the peak detection could be preferable than the canonical linear filtering to reduce aliasing.

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Neuromodulation on neurogenic contraction of electrical nerve stimulation on isolated renal artery of rabbit (토끼 적출 신동맥에 있어서 전기자극에 의한 신경성 수축작용의 neuromodulation 효과)

  • Kim, Joo-heon;Hong, Yong-geun
    • Korean Journal of Veterinary Research
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    • v.36 no.4
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    • pp.821-828
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    • 1996
  • To elucidate the neuromodulation of neuropeptide Y and $\alpha,\;\beta$-methylene ATP on the neurogenic contraction of electrical perivascular nerve stimulation and the contractile response of noradrenaline from polygraph in the isolated renal artery of rabbit. 1. The neurogenic contraction induced by perivascular nerve stimulation was the voltage-dependent manner(10-100V) in the isolated renal artery of rabbit. 2. Neuropeptide Y(0.1uM) and $\alpha,\;\beta$-methylene ATP(1uM) increased the contractile responses of noradrenaline in the isolated renal artery of rabbit. 3. Neuropeptide Y(0.1uM) and $\alpha,\;\beta$-methylene ATP(1uM) increased the neurogenic contraction of electrical perivascular nerve stimulation in the isolated renal artery of rabbit. These results suggest that neuropeptide Y and $\alpha,\;\beta$-methylene ATP neuromodulated on the neurogenic contraction of electrical perivascular nerve stimulation on the isolated renal artery of rabbit.

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A Study on the Empirical Basis of Prejudice towards the Credibility of Persons under Investigation (수사관 편견의 실증적 근거에 관한 연구 - 교통사고 피조사자의 인구사회학적 특성에 따른 수사관의 편견을 중심으로 -)

  • Lee, Ju-Lak;Tark, Jong-Eon
    • Korean Security Journal
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    • no.15
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    • pp.285-301
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    • 2008
  • Police officers have an obligation to their profession to continuously strive for fairness for all the people they serve. However, some police officers are believed to have developed prejudicial attitudes towards some groups of the society and exercised police power unfairly against them. Especially, when the actions of the police are prejudicial during criminal investigation, this can affect outcomes of the investigation. Therefore, the police need to tackle this problem effectively. In order to develop a preventive strategy, the police must have a clear understanding of prejudice. However, there has been little research on this topic in Korea. Thus, this study attempted to fill the gap. The purpose of the current study was to examine if prejudice of police officers are statistically valid. In order to answer this research question, the present study utilized the results of 173 polygraph examinations that had been employed to investigate traffic accidents in a provincial police agency in 2006. From the polygraph examination reports, information relating to the subjects could be identified and this information was analyzed, using a logistic regression. The results of the logistic regression revealed that most of the variables relating to the subjects did not affect the credibility of the subjects' statements. This means the police officers' belief that some groups of people make false statements more often than others during criminal investigation is an unfounded prejudice.

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Aspirin Reduces Acute Lung Injury in Rats Subjected to Severe Hemorrhage (Aspirin이 출혈성 쇼크로 인한 급성 폐손상에 미치는 효과)

  • Shin, Tae Rim;Lee, Dong Uk;Park, Yoon-Yub
    • Tuberculosis and Respiratory Diseases
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    • v.54 no.5
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    • pp.522-531
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    • 2003
  • Background : Hemorrhagic shock and trauma are two of the most common causes of acute lung injury. The activation of cyclooxygenase is one of the important causes of acute lung injury. This study investigated the effect of aspirin, a well-known cyclooxygenase inhibitor, on severe hemorrhage-induced acute lung injury in rats. Methods : The hemorrhagic shock was induced by withdrawing blood; 20ml/kg of B.W., through the femoral artery in 5 min. The mean arterial pressure was recorded through the femoral artery on a polygraph. Results : In the present investigation, the lung tissue myeloperoxidase activity, protein contents and leukocyte counts, in bronchoalveolar lavage fluid, increased significantly 2 and 24 h after the hemorrhage induction. Although the decreased mean arterial pressure spontaneously recovered, acute lung injury occurred after severe hemorrhage. These changes were effectively prevented by a single intravenous injection of aspirin (10 mg/kg of B.W.) 30 min before the hemorrhage. Conclusion : These results suggest that severe hemorrhage-induced acute lung injury is mediated, in part, by the activation of cyclooxygenase. Furthermore, pretreatment of aspirin in acute lung injury-prone patients, or prophylactic treatment of aspirin to the patients with precipitating conditions, could be helpful in the prevention of acute lung injury.

The Inhibition Effect of Water Extract of Acanthopanax senticosus Harms Roots on the 5-HT Induced Vasocontraction in Rat

  • Kim, Hyung-Hwan;Ahn, Duk-Kyun;Yook, Chang-Soo;Choi, Ho-Young
    • The Journal of Korean Medicine
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    • v.24 no.4
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    • pp.82-86
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    • 2003
  • Objective : To examine the inhibition of 5-Hydroxytryptamine(5-HT) induced vasocontraction of the water extract of Acanthopanax senticosus Harms roots (ASR) on rat thoracic Aorta and mesenteric artery with and without endothelium. Methods : Segments of thoracic aorta and mesenteric artery obtained from rats immediately after delivery were mounted in organ baths superfused on a polygraph. Results : We found that the thoracic aorta segments responded to the water extract of ASR with a dose-dependent and concentration-dependent vasorelaxation. 5-HT produced a concentration-dependent contraction of the thoracic aorta and mesenteric artery. At high concentrations of ASR, the inhibition responses were 93.7% (Jang-su), 93.5% (Heok-ryong-kang-sung), 92.8% (Mt. Back-doo), and 83.5% (Yeon-byun) of the maximum 5-HT induced contraction. At high concentrations of ASR, the relaxational response at thoracic aorta and mesenteric artery wi1h endothelium were 95.2% and 94.6%; without endothelium were 93.5% and 92.5% of 1he maximum 5-HT induced contraction. Conclusions : In conclusion, the effect of water extract of ASR had potent inhibition at 5-HT and the effect of ASR in isolated thoracic aorta and mesenteric artery showed dose-dependent inhibition but endothelium-independent response.

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The Effect of Rheum palmatum L. and Rheum undulatum L. on Rat Thoracic Aorta and Abdominal Aorta

  • Kim, Tack;Kim, Hyung-Hwan;Ahn, Duk-Kyun;Choi, Ho-Young
    • The Journal of Korean Medicine
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    • v.24 no.4
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    • pp.87-91
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    • 2003
  • Objectives: To examine the relaxational response to the water extract of Rheum palmatum L. and Rheum undulatum L. on rat thoracic aorta and abdominal aorta. Methods: Segments of thoracic aorta and abdominal aorta obtained from rats immediately after delivery were mounted in organ baths superfused on a polygraph. Results : We found that the thoracic aorta segments responded to the water extract of genus Rheum with a dose-dependent vasorelaxation. At $10^{-4}$ M 5-HT, the maximal contraction force was 93.5% of the maximum KCI-response. The 5-HT induced contractions at $10^{-4}$ M were inhibited by 86.4% and 62.1 % after addition of the high concentrations of R. palmatum root (RPR) and leaf (RPL) and R. undulatum root (RUR) and leaf (RUL). At 10 mg/ml RPR and RUR, the relaxational response at thoracic aorta and abdominal aorta with and without endothelium were 86.4%, 83.2%, 85.8%, and 62.1% of the maximum 5-HT induced contraction. Conclusion: Our result showed that RPL and RUL induced dose-dependent vasorelaxation on rat thoracic aorta and abdominal aorta, and that RPL and RUL roots have more potent effects than the leaves.

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Effect of Caerulein on the Isolated Gall Bladder Strips of Rabbits (토끼 담낭절펼에 대한 Caerulein의 작용)

  • Cho, T.S.;Lee, W.C.;Hong, S.S.
    • The Korean Journal of Pharmacology
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    • v.10 no.1 s.15
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    • pp.47-52
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    • 1974
  • The isolated rabbit gall bladder strips were prepared according to the technique described by Amer and Becvar (1969). The strips were placed in a bath containing 100 ml of Locke-Ringer solution maintained at $38^{\circ}C$. Oxygen was continuously bubbled through the solution. The tension of the muscle strip was initially adjusted to 0.7g. The contractile response was measured isometrically by a force-displacement transducer connected to a polygraph. The effect of a number of autonomic drugs were studied for their interaction with caerulein (Prof. V. Erspamer, F.I. 6934 Caerulein, Farmitalia, Italia), a gastrin or CCK.PZ like peptide, on isolated rabbit gall bladder strips. In this preparation caerulein produced contractions of CCK-PZ type, but the relative potency on a weight basis was 40 times that of CCK-PZ. The response of caerulein was not modified by either cholinergic or alpha or beta adrenergic blockade. However, the response of caerulein and of barium on the strips were prevented by papaverine or aminophylline. Isoproterenol, papaverine or aminophylline alone relaxed the preparation whereas caerulein, CCK-PZ, acetylcholine, serotonin, histamine or barium chloride contracted the preparation. In summary, it is concluded that caerulein on the gall bladder strip seems to act independently of the autonomic nervous system and mediated via mechanisms apparently similar to those involved in the action of barium chloride.

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Relaxative Effect of Transmural Nerve Stimulation via ${\beta}$-adrenergic Nerve on the Isolated Uterine Smooth Muscle Motility of Pigs (돼지 적출 자궁 평활근의 운동성에 있어서 transmural nerve stimulation에 대한 ${\beta}$-adrenergic 신경의 이완작용)

  • Kim, Joo-Heon;Jeon, Jae-Cheul;Rho, Gyu-Jin;Hong, Yong-Geun;Choe, Sang-Yong
    • Journal of Veterinary Clinics
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    • v.23 no.4
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    • pp.421-426
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    • 2006
  • The effects of transmural nerve stimulation induced releasing neurotransmitters on the changes of swine uterine smooth muscle motility were examined by polygraph through isometric force transducer. The frequency dependent relaxation and rebound contraction were revealed on precontraction with histamine by transmural nerve stimulation. The rebound contraction by transmural nerve stimulation was inhibited by nonselective ${\alpha}$-adrenergic receptor antagonist, phentolamine, and the relaxation by transmural nerve stimulation was blocked by nonselective ${\beta}$-adrenergic receptor antagonist, propranolol. The relaxation induced by nonselective ${\beta}$-adrenergic receptor agonist, isoproterenol on precontraction with histamine were the dose dependent manner and this relaxation was blocked by nonselective ${\beta}$-adrenergic receptor antagonist, propranolol in isolated uterine smooth muscle of pig. These results suggest that endogenous neurotransmitters on smooth muscle relaxation was influenced by ${\beta}$-adrenergic receptor in swine.