• Title/Summary/Keyword: scales

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The end effector of circadian heart rate variation: the sinoatrial node pacemaker cell

  • Yaniv, Yael;Lakatta, Edward G.
    • BMB Reports
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    • v.48 no.12
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    • pp.677-684
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    • 2015
  • Cardiovascular function is regulated by the rhythmicity of circadian, infradian and ultradian clocks. Specific time scales of different cell types drive their functions: circadian gene regulation at hours scale, activation-inactivation cycles of ion channels at millisecond scales, the heart's beating rate at hundreds of millisecond scales, and low frequency autonomic signaling at cycles of tens of seconds. Heart rate and rhythm are modulated by a hierarchical clock system: autonomic signaling from the brain releases neurotransmitters from the vagus and sympathetic nerves to the heart's pacemaker cells and activate receptors on the cell. These receptors activating ultradian clock functions embedded within pacemaker cells include sarcoplasmic reticulum rhythmic spontaneous Ca2+ cycling, rhythmic ion channel current activation and inactivation, and rhythmic oscillatory mitochondria ATP production. Here we summarize the evidence that intrinsic pacemaker cell mechanisms are the end effector of the hierarchical brain-heart circadian clock system.

The Study on the Relations of Coffee and MMPI (커피와 MMPI와의 관련성)

  • Seo Eun-Mi
    • Journal of Oriental Neuropsychiatry
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    • v.2 no.1
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    • pp.94-107
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    • 1991
  • This clinical study was done to investigate how the perticular elements of coffee reflects a person using MMPI (Minesota Multiphasic Personality Inventory) as a guide. This study was done based on the sample groups of 29 coffee-drinking-studensts and 21 non-coffee-drinking students. The results were as follows ; 1. The mean T-scores on all the scales were within normal range in coffee-drinking-group. 2. The personal traits of coffee-drinking-group showed elevated scales of Hs, D, Hy and Pt and showed 3, 1, 2 profile type. 3. Comparing non-coffee-drinking-group with coffee-drinking-group, scales of Hs, D, Hy, Mf, Pt, Ma were significantly higher in the latter. 4. According to pattern analysis, Psycho-neurotic trait was recognized in 62.07% of non-coffee-drinking-group, 76.19% of coffee-drinking-group. As a result, aboves support the exiting hypothesis that coffee give rise to Blood-asthenia(血虛) and Spleen-Lack of transports(脾不運化) and have an influence on neurosis, psychosis and sleep disturbance.

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Characteristization of Spray Combustion and Turbulent Flame Structures in a Typical Diesel Engine Condition (디젤 엔진 운전 조건에서 분무 연소 과정과 난류 화염 구조 특성에 대한 해석)

  • Lee, Young-J.;Huh, Kang-Y.
    • Journal of the Korean Society of Combustion
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    • v.14 no.3
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    • pp.29-36
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    • 2009
  • Simulation is performed to analyze the characteristics of turbulent spray combustion in a diesel engine condition. An extended Conditional Moment Closure (CMC) model is employed to resolve coupling between chemistry and turbulence. Relevant time and length scales and dimensionless numbers are estimated at the tip and the mid spray region during spray development and combustion. The liquid volume fractions are small enough to support validity of droplets assumed as point sources in two-phase flow. The mean scalar dissipation rates (SDR) are lower than the extinction limit to show flame stability throughout the combustion period. The Kolmogorov scales remain relatively constant, while the integral scales increase with decay of turbulence. The chemical time scale decreases abruptly to a small value as ignition occurs with subsequent heat release. The Da and Ka show opposite trends due to variation in the chemical time scale. More work is in progress to identify the spray combustion regimes.

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Dynamic Analysis of Harmonically Excited Non-Linear System Using Multiple Scales Method

  • Moon, Byung-Young;Kang, Beom-Soo
    • Journal of Mechanical Science and Technology
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    • v.16 no.6
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    • pp.819-828
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    • 2002
  • An analytical method is presented for evaluation of the steady state periodic behavior of nonlinear systems. This method is based on the substructure synthesis formulation and a MS (multiple scales) procedure, which is applied to the analysis of nonlinear responses. The proposed procedure reduces the size of large degrees-of-freedom problem in solving nonlinear equations. Feasibility and advantages of the proposed method are illustrated with the nonlinear rotating machine system as an example of large mechanical structure systems. In addition, its efficiency for nonlinear response prediction will be shown by comparison of other conventional methods.

An Analysis of Regional Noise Reaction for the International Standardized Noise Annoyance modifiers (국제 표준 소음평가 어휘 설정을 위한 지역별 거주자의 반응분석)

  • Kim, Kyong-Ho;Jeon, Jin-Yong;Yano, T.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.559-564
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    • 2002
  • Recently a number of social surveys on community response to environmental noises have been conducted. Since standardized noise annoyance scales were needed to compare the results from various areas. ICBEN(International Commission on Biological of Noise) Team 6 planned a international joint study and constructed comparable standardized noise annoyance scales using the same method. In Korea the survey was conducted in four areas such as Seoul, Taejon, Taegu and Kwangju. About 100 subjects participated in each area approximately. The 21 adverbs were first in the carly survey, and five verbal annoyance modifiers were finally constructed as follows; 1(Jeonhyo), 2(Jokm), 3(Bikyojerk)m, 4(Ajoo), 5(Umcheongnage)

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Scale Morphologies for Identification of Marine Nanoflagellates (해양 미소 편모조류의 종 동정을 위한 인편 형태에 관한 연구)

  • Kim, Hyeung-Sin;Jung, Min-Min
    • ALGAE
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    • v.20 no.4
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    • pp.305-314
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    • 2005
  • 5 Haptophyta 2 Chrysophyta and 1 Prasinophyta species of scale-bearing nanoflagellates were collected in coastal water of Korea and identified by examination of their scales with Field Emission Scanning Electron Microscope (JSM-6700F). These included Chrysochromulina ahrengoti, C. simplex, C. spinifera, Prymnesium parvum, P. patelliferum, Mamiella gilva, Paraphysomonas imperforata and Pa. vestita. The surface of cells covered with unmineralised scales (5 Haptophyte and 1 Prasinophyta species) or silica scales (2 Chrysophyta species). Scale-covered flagella are found in the 1 Prasinophyta species. One of the main structural characteristics of Haptophyte is the haptonema, a filiform organelle which occurs together with the two flagella. It may be long and coiling upon irritation as in Chrysochromulina, or short and noncoiling as in Prymnesium.

A multiscale creep model as basis for simulation of early-age concrete behavior

  • Pichler, Ch.;Lackner, R.
    • Computers and Concrete
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    • v.5 no.4
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    • pp.295-328
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    • 2008
  • A previously published multiscale model for early-age cement-based materials [Pichler, et al.2007. "A multiscale micromechanics model for the autogenous-shrinkage deformation of early-age cement-based materials." Engineering Fracture Mechanics, 74, 34-58] is extended towards upscaling of viscoelastic properties. The obtained model links macroscopic behavior, i.e., creep compliance of concrete samples, to the composition of concrete at finer scales and the (supposedly) intrinsic material properties of distinct phases at these scales. Whereas finer-scale composition (and its history) is accessible through recently developed hydration models for the main clinker phases in ordinary Portland cement (OPC), viscous properties of the creep active constituent at finer scales, i.e., calcium-silicate-hydrates (CSH) are identified from macroscopic creep tests using the proposed multiscale model. The proposed multiscale model is assessed by different concrete creep tests reported in the open literature. Moreover, the model prediction is compared to a commonly used macroscopic creep model, the so-called B3 model.

MMPI of Out-Patients with Irritable Bowel Syndrome (과민성 대장증후군 내원환자의 MMPI 군집분석)

  • Park, Keon-Young;Cho, Sun-Mi;Chung, Young-Ki
    • Korean Journal of Psychosomatic Medicine
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    • v.4 no.1
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    • pp.54-63
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    • 1996
  • In this cluster analysis of out-patients with irritable bowel syndrome (IBS) we described the psychological features and personality patterns of these patients. The Minnesota Multiphasic Personality Inventory (MMPI) was administered to 29 IBS patients who received treatment in the gastroenterology department of Ajou University Hospital to produce individual profiles for each patient. The 29 profiles with 13 standard scales, 15 content scales and 11 personality scales were subjected to cluster analysis resulting in three clusters of the original sample. Titles used to describe the psychological features and personality patterns seen in the three clusters included : (1) depression and anxiety : (2) somatization and denial of affect ; (3) anger overcontrol. Future studies on the treatment of IBS patients may well consider these features, as IBS patients have different psychological patterns.

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PECULIARITY IN SCALE CHARACTERS OF ENGRAULIDAE FISHES (멸치과어류의 비늘의 특이성)

  • KIM Yong Uk
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.11 no.4
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    • pp.249-256
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    • 1978
  • Morphological characters of the scales of Engraulidae fishes, Engraulis japonica and Thrissa kammalensis, are described with illustrative figures. The scales are primitive cycloid and quadrangular or pentagonal without concentric foci. In Engraulis japonica arrangements of the grooves are irregular, and tile grooves converge from the outer margin to the central part of the scale. In Thrissa kammalensis the arrangements of the grooves are transverse in the major part of the scale except the apical part. The ridge of the apical part form a network arrangement, and parallel with the grooves. In the central part of the scales of the both species there are several fingerprint-like structures.

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A Study on the Comparative Analysis of Architectural Scale in Yun, Jeung and Kim, Gi-Ung's Houses (윤증(尹拯) 고택(古宅)과 김기응(金幾應) 가옥(家屋)의 건축척도 비교분석에 관한 연구)

  • Hahn, Sang min;Han, Jo Dong;Rhee, Kang Hoon
    • Journal of the Korean Institute of Rural Architecture
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    • v.4 no.2
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    • pp.13-25
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    • 2002
  • The study analyzed Yun, Jeung and Kim, Gi-Ung's Houses to understand the architectural scales adopted by them by comparing the composition of factors forming the whole architectural space. The result is as follows. Yun, Jeung's House intentionally adopted the normative order from its initial constuction to its completion, and Kim Gi-Ung's House periodically did different architectural scales whenever its anchae was extended. The architectural scale was the basic system to harmonize those houses part and part or part and whole.

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