• Title/Summary/Keyword: Second derivative

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Gender-Related Differences in the Second Derivative of Photoplethysmogram Waveforms in the Fourth Decade (30대 성인남녀의 성별에 따른 가속도맥파 차이에 관한 연구)

  • 남동현;박연재;박영배
    • The Journal of Korean Medicine
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    • v.23 no.3
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    • pp.1-10
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    • 2002
  • Objective: There exist gender differences in pulsatile contour waveform. Women have a greater age-related increase in left ventricular mass than do men and more likely to experience symptomatic heart failure after infarction. SDPTG (the second derivative of photoplethysmogram waveform) is a noninvasive method for evaluating the pulse wave and is correlated with age and other risk factors for atherosclerosis. We studied the effect of gender on SDPTG and made clear why the gender differences appear. Methods: To study the effects of effect factors, including height and blood pressure, on SDPTG in the fourth decade, data on height, weight, PTD (pulse transit distance), blood pressure, serum lipid levels, and SDPTG were collected in 115 laboratory healthy men and women. SDPTG is derived from double-differential processing of fingertip photoplethysmography and consists of a, b, c, and d waves in systole and an e wave in diastole; SDPTG aging index (AI) was calculated as (b-c-d-e)/a. Results: There were significant gender-related differences of SDPTG AI, height, and blood pressure. Age, height, and mean blood pressure were respectively and significantly correlated with SDPTG AI. SDPTG is dependent upon age, height, and blood pressure. Restricting analysis to SDPTG AI, age, height, and mean blood pressure, yielded that there were gender-related differences in SDPTG AI (P<0.05) which were derived from those of height (F<0.001, df=l, P=0.994). Conclusions: These new data may help to explain previous findings about age-related differences in pulsatile contour waveforms and why gender differences of SDPTG appear. The results of this study suggest that SDPTG AI, used for evaluation of biological vascular aging, should be calibrated by height as well as age and blood pressure.

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Study on the Relationship between Carotid Intima-Media Thickness and The Second Derivative of Photoplethysmogram Waveforms in Ischemic Stroke Patients (뇌경색 환자의 경동맥 내막 두께와 사속도맥파 검사의 관련성 연구)

  • Kang, Kyung Hwa;Kim, Kyoung Min
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.29 no.2
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    • pp.160-167
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    • 2015
  • The purpose of this study was to investigate the correlation of Intima-Media Thickness of common carotid artery(CCA-IMT) and The Second Derivative of Photoplethysmogram Waveforms(SDPTG). 38 subjects with acute ischemic stroke were recruited from the patients admitted to Dong-Eui Medical Center from the June 2013 to January 2014. We assessed 38 patient's SDPTG data and CCA-IMT data by B Mode ultrasonography. then 38 subjects were divided into two groups by the CCA-IMT difference; CCA-IMT 〈 0.8 mm group(n=11), CCA-IMT $$\geq_-$$ 0.8 mm group(n=27). We analyzed their characteristics, risk factor, blood test result, life style by CCA-IMT difference. As a result, Age, Hypertension were significantly higher in the CCA-IMT $$\geq_-$$ 0.8 mm group then in the CCA-IMT < 0.8 mm group. Regular exercise were significantly higher in the CCA-IMT < 0.8 mm group then in the CCA-IMT $$\geq_-$$ 0.8 mm group. The result of Multiple regression analysis on the factors affecting the CCA-IMT was hypertension, total cholesterol, age. and The result of Pearson's Correlation analysis on CCA-IMT and SDPTG is that e/a ratio, SDPTG AI were respectively and significantly correlated with CCA-IMT. According to the analysis, the Relationship between CCA-IMT and SDPTG in Ischemic Stroke Patients were founded. We suggest that further investigation with larger and better controlled trials of the Relationship between CCA-IMT and SDPTG could contribute to better understand the effects of risk factors on atherosclerosis.

Structure of Water-Methanol Mixtures Studied by NIR Spectroscopy

  • Adachi, Daisuke;Katsumoto, Yukiteru;Sato, Harumi;Ozaki, Yukihiro
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1283-1283
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    • 2001
  • NIR spectroscopy has been used extensively to investigate the structure of water, alcohol and other self-associate molecules because the frequencies of NIR bands due to OH and NH groups strength of hydrogen bonds. We have studied the structure of water -methanol mixtures by use of NIR spectroscopy. Strong features in the 7200-6300 $cm^{-1}$ / region consist of a number of overlapped bands due to the combination of OH antisymmetric and symmetric stretching modes of water and the first overtone of the OH stretching modes of free and hydrogen bonded methanol, while weak fratures in the 6000-5800 cm-1 region are ascribed to the first overtones of $CH_3$ stretching modes of methanol. We will focus the discussion on the $CH_3$ stretching bands. They seem to show a significant shift is not clear from the spectra shown in figure 1(a). Figure 1(b) depicts the second derivative in the 6000-5700 $cm^{-1}$ / region. Now, it is clear from the second derivative that there are two major bands near 5950 and 5900 $cm^{-1}$ / and that they do show a shift be about 30 $cm^{-1}$ / Why do the $CH_3$ bands show the shift with increasing concentration of methanol\ulcorner Probably, the CH, group interacts directly with OH groups of water. The results in figure 1(b) demonstrate the usefulness of the second derivative in resolution enhancement as well as the potential of NIR spectroscopy in the studies of molecular interactions.(Figure omitted).

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A Study on the Structure and Origin of the Dokdo and it's Surroundings in the East Sea (Japan Sea) Using Magnetic Anomalies (지자기이상을 이용한 동해 독도 및 독도주변의 구조와 성인에 관한 고찰)

  • Kim, Chang-Hwan;Park, Chan-Hong;Min, Kyung-Duck;Han, Hyun-Chul;Kwon, Moon-Sang;Shim, Jae-Seol;Choi, Sung-Ho;Oh, Soon-Bock
    • Ocean and Polar Research
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    • v.24 no.4
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    • pp.491-500
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    • 2002
  • Magnetic anomalies in the Dokdo and it's surroundings were investigated with respect to structure and origin of the Dokdo and surrounding seamounts. After normal and diurnal correction of measured magnetic data, crossover correction was applied to reduce errors between sets of magnetic anomalies. The errors from crossover operation result in decrease of about 51%, from 62.2 nT to 30.1 nT in standard deviation. Reduction-to-the-pole, second vertical derivative and analytic signal processing were applied to explore magnetic anomaly signatures in detail. Magnetic anomalies are most complicated in the 1st-Dok seamount, show SWW-NEE linear pattern in the 2nd-Dok seamount and lower to the 3rd-Dok seamount. Different magnetic anomaly patterns in three seamounts imply that three volcanic seamounts were formed at different times and are composed of rocks that were produced in different conditions. It seems that the 3rd-Dok seamount was first to form and followed by the 1st-Dok seamount. The complicated magnetic and second vertical derivative anomaly patterns in the 1st-Dok seamount may be due to subsidiary cones around crater or the presence of intruded magma bodies below sea surface and the Dokdo is probably a marginal subsidiary part of crater.

A Study on the Correlation between the Second Derivative of Photoplethysmogram and Quality of Life using SF-36 Questionnaire in Women (광용적맥파와 SF-36을 이용한 여성의 삶의 질 관계 연구)

  • Jang, Young-Hun;Park, Young-Jae
    • The Journal of Korean Medicine
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    • v.41 no.2
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    • pp.34-42
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    • 2020
  • Background and Objectives: The purpose of this study was to examine the relationship between between one's quality of life (QoL) level and the arterial stiffness estimated by the second derivative of photoplethysmogram (SDPTG) for women patients. Methods: A retrospective chart review was performed on charts of 407 women patients (38.38±11.82 years) who visited Gangdong Kyung Hee Hospital between April 1st and September 30th, 2011. Vascular aging index (VAI, (b-c-d)/a), b/a, c/a, and d/a were considered as the arterial stiffness indexes, and the Korean version of the Short-Form 36 (SF-36) were completed to estimate one's physical and mental QoL. Results: Physical and mental components of the SF-36 in older group (50, 60, and 70 years-group) were lower than those in younger group (20 and 30 years-group). Large arterial stiffness-related b/a in older group was higher that in younger group, while small arterial stiffness-related d/a in older group was lower that in younger group. Physical and mental component scores of the SF-36 had the negative correlations with VAI and b/a (r; -0.153~-0.195), while had the positive correlations with c/a and d/a (r; 0.147~0.228). Conclusions: In conclusion, this study suggests that convenient and cost-effective SDPTG test may serve as an auxiliary tool to estimate one's physical and mental QoL.

Effects of Acupuncture at Palsa(BaXie) Evaluated by the Second Derivative of Photoplethysmogram Waveform in Hemiparetic Patients after Stroke (편마비 환자에서 팔사혈(八邪穴) 자침(刺鍼)이 가속도맥파에 미치는 영향)

  • Yeo, Kyeong-Chan;Yoon, In-Ae;Kim, Ji-Na;Bang, Sung-Pil;Moon, Sung-Il
    • Journal of Acupuncture Research
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    • v.27 no.2
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    • pp.23-30
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    • 2010
  • Objectives : The second derivative of photoplethysmogram waveform(SDPTG) is a simple, convenient and non-invasive technique for pulse wave analysis. This study was designed to investigate the differences in the SDPTG between the affected side and the unaffected side in hemiparetic patients after stroke, and the effects of acupuncture at Palsa(BaXie) in hemiparetic patients after stroke. Methods : To evaluate the differences between the affected side and the unaffected side in hemiparetic patients after stroke, their SDPTG were recorded by using a Cardio Peri SA6000. To evaluate the effects of acupuncture at Palsa(BaXie) in 20 hemiparetic patients after stroke and 20 healthy subjects, their SDPTG were recorded 2 times(pre-acupuncture and post-acupuncture). The SDPTG consists of an a, b, c and d wave in systole and an e wave in diastole. Sano aging index was defined as (b-c-d)/a. Results : 1. The affected side in hemiparetic patients after stroke had higher average b/a ratio(p<0.05)and Sano aging index(p<0.05) than the unaffected side 2. In a comparison of pre-acupuncture and post-acupuncture at the Palsa(BaXie), b/a ratio(p<0.05) and Sano aging index(p<0.05) was decreased significantly in both hemiparetic patients and healthy subjects. Conclusions : These findings suggest that acupuncture at Palsa(BaXie) may be effective method of reverting some of the deleterious effects on vascular function produced by stroke.

Effect of Acetylation on Conformation of Glycinin (아세틸화가 Glycinin의 구조에 미치는 영향)

  • Kim, Kang-Sung;Rhee, Joon-Shick
    • Korean Journal of Food Science and Technology
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    • v.21 no.5
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    • pp.714-720
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    • 1989
  • Effects of acetylation on conformational changes of glycinin was studied using solvent perturbation, second derivative spectroscopy, near uv circular dichroism spectra and viscosity. Glycinin with purity of more than 93% was used for the experiment. Modification was carried out with acetic anhydride and glycinin with lysine residue modification of 0%, 28%, 65%, 85%, and 95% were used for the experiment. The result of solvent perturbation using some selected perturbants, such as glycerol, ethylene glycol, and dimethyl sulfoxide revealed that acetylation has caused increase In solvent accessibility of tyrosine residues from less than 40% in native protein to more than 70% for 95% acetylated glycinin. This was confirmed by second derivative spectroscopy. Near ultraviolet circular dichroism revealed that the spectra of native and acetylated glycinin were almost identical differing only in intensity and no other useful information could be derived from it. However, in the case of 95% acetylated glycinin the influence of tryptophan on the spectrum was more pronounced Specific viscosity of glycinin also increased by modification, the extent of which depended upon the degree of acetylation. These results supported that acetylation had caused globular conformation of glycinin to be expanded and denatured.

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Nonlinear Optical Effect and Optical Properties of Azobenzene Derivative LB Lilm (Azobenzene 유도체 LB막의 광학적 특성 및 비선형 광학 효과)

  • Shin, Dong-Myung;Choi, Kang-Hoon;Kang, Dou-Yol;Jung, Chi-Sup
    • Proceedings of the KIEE Conference
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    • 1994.11a
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    • pp.225-227
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    • 1994
  • The second-order nonlinear optical effect, especially the second harmonic generation, in Langmuir-Blodgett(LB) films have get much attention over the past few years. For second harmonic generation(SHG) of the ultrathin organic films, the multilayer structure of the film should have the noncentrosymmetric arrangements of molecules. The Langmuir-Blodgett technique can result in the production of thin films of precisely controlled dimensions and structure. In this paper, n-octadecyl 4-(4'-nitrophenylazo)-1-naphthyl ether, ONNE(azohenzene derivative), was synthesized and the optical properties of ONNE was studied. Nonccntrosymmctric Z-type LB films of ONNE were prepared and SHG intensity of the film were measured. The structural characteristics of floating monolayer(L film) and LB film of ONNE were discussed with $\pi$-A isotherm. UV-visible absorption spectroscopy and spectroscopic ellipsometry. The polarized UV-visible absorption spectroscopy and SHO intensity suggest the molecular orientation in LB film.

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Splines via Computer Programming

  • 김경태
    • Communications of the Korean Institute of Information Scientists and Engineers
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    • v.1 no.1
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    • pp.72-74
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    • 1983
  • Traditionally, polynomials have been used to approximte functions with prescribed values at a number of points(called the knots) on a given interal on the real line. The method of splines recently developed is more flexible. It approximates a function in a piece-wise fashion, by means of a different polynomial in each subinterval. The cubic spline gas ets origins in beam theory. It possessed continuous first and second deriatives at the knots and is characterised by a minimum curvature property which es rdlated to the physical feature of minimum potential energy of the supported beam. Translated into mathematical terms, this means that between successive knots the approximation yields a third-order polynomial sith its first derivatives continuous at the knots. The minimum curvature property holds good for each subinterval as well as for the whole region of approximation This means that the integral of the square of the second derivative over the entire interval, and also over each subinterval, es to be minimized. Thus, the task of determining the spline lffers itself as a textbook problem in discrete computer programming, since the integral of ghe square of the second derivative can be obviously recognized as the criterion function whicg gas to be minimized. Starting with the initial value of the function and assuming an initial solpe of the curve, the minimum norm property of the curvature makes sequential decision of the slope at successive knots (points) feasible. It is the aim of this paper to derive the cubic spline by the methods of computer programming and show that the results which is computed the all the alues in each subinterval of the spline approximations.

Algorithm of the Detection of the Feature points using distributed feature points of the Second Derivative of Photoplethysmogram waveform (이차 미분 맥파의 변곡점 분포를 이용한 특징점 추출 알고리즘)

  • Kim, Pan-Ki;Ahn, Chang-Beom
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.1988_1989
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    • 2009
  • 본 논문은 이차 미분 맥파(SDPTG, Second Derivation of Photoplethysmogram)를 측정하여 이차 미분 맥파의 5개의 특징점을 검출하는 방법에 대한 내용을 기술한다. 본 논문에서는 측정된 신호의 신호대 잡음비(SNR)을 높이는 방법과 기존의 미분을 이용한 변곡점 추출의 한계적인 부분, 그리고 본 논문에서 제안하는 이차 미분 맥파의 특징점의 분포를 이용한 특징점 추출 알고리즘에 대해서 설명한다.

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