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Age-related Changes of the Finger Photoplethysmogram in Frequency Domain Analysis (연령증가에 따른 지첨용적맥파의 주파수 영역에서의 변화)

  • Nam, Tong-Hyun;Park, Young-Bae;Park, Young-Jae;Shin, Sang-Hoon
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.12 no.1
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    • pp.42-62
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    • 2008
  • Objectives: It is well known that some parameters of the photoplethysmogram (PPG) acquired by time domain contour analysis can be used as markers of vascular aging. But the previous studies that have been performed for frequency domain analysis of the PPG to date have provided only restrictive and fragmentary information. The aim of the present investigation was to determine whether the harmonics extracted from the PPG using a fast Fourier transformation could be used as an index of vascular aging. Methods: The PPG was measured in 600 recruited subjects for 30 second durations, To grasp the gross age-related change of the PPG waveform, we grouped subjects according to gender and age and averaged the PPG signal of one pulse cycle. To calculate the conventional indices of vascular aging, we selected the 5-6 cycles of pulse that the baseline was relatively stable and then acquired the coordinates of the inflection points. For the frequency domain analysis we performed a power spectral analysis on the PPG signals for 30 seconds using a fast Fourier transformation and dissociated the harmonic components from the PPG signals. Results: A final number of 390 subjects (174 males and 216 females) were included in the statistical analysis. The normalized power of the harmonics decreased with age and on a logarithmic scale reduction of the normalized power in the third (r=-0.492, P<0.0001), fourth (r=-0.621, P<0.0001) and fifth harmonic (r=-0.487, P<0.0001) was prominent. From a multiple linear regression analysis, Stiffness index, reflection index and corrected up-stroke time influenced the normalized power of the harmonics on a logarithmic scale. Conclusions: The normalized harmonic power decreased with age in healthy subjects and may be less error prone due to the essential attributes of frequency domain analysis. Therefore, we expect that the normalized harmonic power density can be useful as a vascular aging marker.

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The Findings and Significances of Brain SPECT in Acute Mealses Encephalitis (급성 홍역 뇌증 환아들의 뇌 SPECT 소견과 유용성)

  • Kim, Jung Chul;Choung, Ju Mi;Eun, So Hee;Lee, Dae-Yeol;Kim, Jung Soo
    • Clinical and Experimental Pediatrics
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    • v.45 no.11
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    • pp.1373-1380
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    • 2002
  • Purpose : Acute measles encephalitis(ME) is characterized by an abrupt onset of fever and obtundation, frequently accompanied by seizures and multifocal neurological signs. The aim of this study was to clarify the clinical manifestation, progression and the brain SPECT patterns in patients with acute ME. Methods : This study included 11 children with acute ME admitted to Chonbuk National University Hospital. Ten patients received a first dose of measles vaccine, one patient did not receive a first dose, and no patients received a second dose. ME was diagnosed based on characteristic clinical pictures, measles antibodies by ELISA and abnormal CSF findings. Brain MRI and brain SPECT were performed in 11 patients with acute ME. Results : There were four males and seven females whose ages at onset ranged between 18 months and 14 years(mean : 10.5 years). The main clinical neurologic pictures were loss of consciousness( 10) and seizure(five). The titer of IgG and IgM antimeasles antibodies in serum were positive in 10 patients. In CSF, nine patients had IgG antibodies and one patient had IgM antibodies. The concentration of protein(mean : $124{\pm}60mg/dL$) and WBC counts(mean : $158{\pm}157/{\mu}L$) in CSF were elevated in all patients. In electroencephalographic examination, nine patients showed increased slow waves. Seven of 11 patients(63.6%) revealed high signal intensity on the brain MRI. In contrast, all patients showed hypoperfusion in brain SPECT examination. According to brain SPECT, the perfusion deficits were frequently observed in the frontal lobe(nine), temporal (nine), parietal(eight) and thalamus(eight). Conclusion : Brain SPECT is more sensitive than MRI for the evaluation of brain damage in early stages of acute ME.

Economic Welfare Study on Seasonal and Time Period Electricity Pricing (계시별 전력가격에 대한 경제적 후생 연구)

  • Yoo, Young-Hoon;Kim, SungSoo
    • Environmental and Resource Economics Review
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    • v.14 no.2
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    • pp.519-547
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    • 2005
  • The aim of this study is to analysis how economic welfare lost happens within the present korea seasonal and time period electricity pricing system and find out reasonable electricity price system acceptable during the transitional period of korea electricity industry restructuring To analyze economic welfare lost in the electricity industry, in advance seasonal and time periodic 9 demand curves(summer, spring &fall, winter/peak-load time, middle-load time, low-load time) and one market supply curve are made and then using these demand and supply curve, seasonal and time periodic market equilibrium prices is calculated. Finally, comparing these market equilibrium prices with present regulated classified seasonal and time periodic prices, the whole economic welfare lost in the electricity industry is calculated. The result of this study shows that in 2002, the total economic welfare lost in electricity industry is 137,770 million Won and under present price system, the worst welfare lost is happening seasonally in spring & fall, time periodically in the middle-load time. Specifically analyzing the characteristics of welfare lost, especially on the industry customers and service customers which are applied in seasonal and time periodic pricing, for the industry customers, the welfare lost calculated in this class occupies 51% of the total welfare lost in the whole electricity industry and the worst welfare lost is happening seasonally in spring & fall, time periodically in the middle-load time. For service customers, the welfare lost calculated in this class occupies 13% of the total welfare lost in the whole electricity industry and the worst welfare lost is happening seasonally in summer, time periodically in the peak time Finally, this study was made based on the year of 2002 and KEPCO has practiced two times of rate change until now. The result of rate change was positively analyzed in the direction of economic welfare improvement(welfare improvement achieved by 16.3% compared to 2002 result).

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The Study on Geology and Volcanism in Jeju Island (I): Petrochemistry and $^{40}Ar/^{39}Ar$ Absolute ages of the Subsurface Volcanic Rock Cores from Boreholes in the Eastern Lowland of Jeiu Island (제주도의 지질과 화산활동에 관한 연구 (I): 동부지역 저지대 시추코어 화산암류의 암석화학 및 $^{40}Ar/^{39}Ar$ 절대연대)

  • Koh, Gi-Won;Park, Jun-Beom;Park, Yoon-Suk
    • Economic and Environmental Geology
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    • v.41 no.1
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    • pp.93-113
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    • 2008
  • This study presents petrochemistry and $^{40}Ar/^{39}Ar$ absolute ages of subsurface volcanic rock cores from twenty(20) boreholes in the eastern lowland (altitude loom below) of Jeju Island, Handeong-Jongdal-Udo-Susan-Samdal-Hacheon areas, and discusses topography and volcanism in the area. The subsurface volcanic rock cores are mainly basalts in composition with minor tholeiitic andesites and basaltic trachyandesites. Sequences of intercalated tholeiitic, transitional and alkalic lavas suggest that tholeiitic and transitional to alkalic lavas must have erupted contemporaneously. Especially, occurrences of trachybasalts and basaltic trachyandesites at the bases in the area imply that the volcanism in the area was initiated with slightly differentiated alkaline magma activity. The $^{40}Ar/^{39}Ar$ absolute ages of the subsurface volcanic rock cores range from $526{\pm}23ka\;to\;38{\pm}4Ka$. The lava-forming Hawaiian volcanic activities of the eastern lowland can be divided into five sequences on the basis of sediment distribution, whole rock geochemistry and $^{40}Ar/^{39}Ar$ absolute ages of the subsurface volcanic rock cores; stage I-U$(550{\sim}400Ka)$, stage II$(400{\sim}300Ka)$ and stage III$(300{\sim}200Ka)$ during syn-depositional stage of Seoguipo Formation, and stage IV$(200{\sim}100Ka)$ and stage V(younger than 100Ka) during post-depositional stage. In the eastern lowland of Jeju Island, compositional variations and local occurrences of the subsurface volcanic rocks as well as existences of various intercalated sediment layers (including hydrovolcanogenic clasts) suggest that the volcanism must have continued for long time intermittently and that the land has been progressively glowed from inland to coast by volcanic activities and sedimentation. It reveals that the subsurface volcanic rocks in the eastern lowland of Jeju Island must have erupted during relatively younger than 200Ka of stages IV and V. The results of this study are partly in contrast with those of previous studies. This study stresses the need that previous reported volcanic activities in Jeju Island based on K-Ar ages of volcanic rocks should be carefully reviewed, and that stratigraphic correlation from boreholes should be conducted by quantitative criteria combined with petrography and petrochemstry as well as radiometric studies of volcanic rock cores.

Diatom Assemblages and its Paleoceanography of the Holocene Glaciomarine Sediments from the Western Antarctic Peninsula shelf, Antarctica (남극반도 서 대륙붕의 빙해양 퇴적물의 규조군집 특성과 고해양 변화)

  • Shin, Yu-Na;Kim, Yea-Dong;Kang, Cheon-Yoon;Yoon, Ho-Il
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.6 no.3
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    • pp.152-163
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    • 2001
  • Based upon the sedimentological, geochemical and micropaleontological analyses of two sediment cores from the Antarctic Peninsula (AP), three distinct lithological units can be recognized: (1) ice-proximal an/or ice-distal diamictons in the lower part of the cores, accumulated just seaward of the grounding line of the ice shlef until 11,000 yrs BP; (2) diatomaceous mud between 6,000 and 2,500 yrs BP in the middle part, resulted from a large influx of organic materials by enhanced production of open marine condition; (3) diatomaceous sandy mud since 2,500 yrs BP, characterized by an increase in sand content and decrease in TOC and diatom abundance in the lower layers, which reflects the formation of more extensive and seasonally persistent sea ice. Based on the C-14 radiocarbon dating, the sub-ice shlef deposition of the diamicton on the AP western shelf completed around 11,000 yrs BP. Colder condition was reinstated between 12,800 and 11,600 BP with a dropin TOC content and diatom abundance, which is coincident with the Younger Dryas event in the North Atlanticregion. At this time, the ice shelf, that is now absent in the study area, appears to advance as evidenced by an abrupt increase in sea-ice taxa. A climatic optimum is recognized between 9,000 and 2,500 BP, coincide witha mid-Holocene climatic optimum 'Hypsithermal Warm Period' from the other Antarctic sites. During this time, diatomaceous mud accumulated by a large influx of organic materials by enhanced production occurred in openmarine condition. Around 2,500 BP, diatomaceous sandy mud reflects the formation of more extensive and seasonally persistent sea ice, coincident with the onset of the Neoglacial in the Antarctic. Our results provide evidence of climatic change from the Antarctic Peninsula`s western shelf that helps in determining the existence and timing of Holocene milennial-scale climatic events in the Southern Hemisphere.

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Effect of PLA2 Inhibitor Rutin on Endotoxin-Induced Acute Lung Injury (내독소로 유도된 급성폐손상에서 PLA2의 억제제인 Rutin의 효과)

  • Kim, Seong-Eun;Lee, Young-Man;Park, Won-Hark
    • Applied Microscopy
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    • v.34 no.1
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    • pp.31-42
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    • 2004
  • Acute respiratory distress syndrome (ARDS) is a kind of acute lung injury characterized by inflammatory disruption of alveolar-capillary barrier and notorious for its high mortality. Neutrophils cause cell damage through the production of free radicals, inflammatory mediators, and proteases in ARDS. $PLA_2$ might serve a primary regulatory role in the activation of neutrophils. This present study was performed to elucidate the effect of rutin known as $PLA_2$ inhibitor on ARDS induced by endotoxin. Endotoxin had increased lung myeloperoxidase (MPO) activity, BAL (bronchoalveolar lavage) protein content, numbers of neutrophils in BALF (bronchoalveolar lavage fluid) compared with those of control rat (p<0.001). In addition, histological evidence of lung injury was correlated with neutrophil influx into alveolar space and cerrous perhydroxide granules were found in lining of endothelial cell, alveolar type I, II cells. In contrast, pretreated group of rutin had significantly decreased all of the parameters (p<0.001). These data suggest that inhibition of $PLA_2$ is one step approach that block the process of ARDS. Accordingly, we conclude that rutin can be used as the prophylactic agent for ARDS on the bases of these experimental results.

BOLD Responses to Acupuncture on Each Side of ST36 (족삼리 좌우측 자침에 대한 BOLD 반응)

  • Yeo, Sujung;Bae, Seong-In;Choe, Ilwhan;Jahng, Geon-Ho;Lim, Sabina
    • Korean Journal of Acupuncture
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    • v.31 no.1
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    • pp.20-32
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    • 2014
  • Objectives : There has been some controversy about the modulatory effects on brain function during acupuncture on each side of the same acupoint. This study was designed to investigate and compare the blood oxygen level-dependent(BOLD) responses of acupuncture on each side of ST36. Methods : Fourteen healthy subjects were recruited for imaging and received acupuncture or placebo stimulations either on the left or on the right acupoint of ST36 in each scan. For the voxel-wise statistical analysis, one sample T-test and the within-subject analysis of variance(ANOVA) test were performed using SPM8 software. Results : This study showed that acupuncture on each side of ST36 showed different BOLD signal patterns. Higher BOLD responses after acupuncture stimulations at the left ST36 compared to the right were observed mainly in the parahippocampal gyrus(BA 28), dorsolateral prefrontal cortex(DLPFC, BA 44), thalamus, culmen and claustrum. We investigated the different neural responses between rest and activation periods of placebo and acupuncture stimulations on each side of ST36. Acupuncture at the right ST36 elicited activation mainly in the insula, supplementary motor area(SMA) and anterior cingulate cortex(ACC), while acupuncture at the left ST36 elicited activation mainly in the insula, primary somatosensory cortex(SI, BA 2) and DLPFC(BA 44). Conclusions : To our knowledge, this is the first reported functional MRI study directly comparing when needling at the right and at the left side of ST36. This study's preliminary results proved to be evidence of acupuncture's different effects when performed on opposite sides of an acupoint.

Histamine Bronchial Provocation Test -Timed Tidal Breathing Technique- (히스타민 기관지유발 검사 -일정시간 흡입법-)

  • Chung, Yeon-Tae;Won, Kyung-Sook;Park, Hae-Shim
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.3
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    • pp.270-276
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    • 1994
  • Background: The measurement of nonspecific bronchial hyperreactivity is valuable for diagnosis and management of bronchial asthma. Methacholine or histamine is used for the pharmacologic provocation test. Usually a methacholine bronchial provocation test is performed by a dosing technique with counted number of breaths. A dosimeter is indispensable in the dosing technique. Recently a timed tidal breathing technique which dose not need an expensive dosimeter was introduced. We measured the degree of nonspecific bronchial hyperreactivity to histamine using a simple timed tidal breathing technique. Method: Forty two healthy volunteers, 12 patients with bronchial asthma(BA), 10 patients with rhinitis(RH) and 10 patients with upper respiratory infection(URI) participated in the study. The subject's nose was clipped and inhalation continued during tidal breathing for 2 minutes via a face mask. $FEV_1$ was measured at 30 seconds, 90 seconds after inhalation and inhalation of next solution was continued until there was a fall in $FEV_1$ of 20%. Histamine PC20 was defined as the concentration at 20% fall of $FEV_1$ and it was obtained from the log dose-response curve by linear interpolation. Results: Inhalation of serial dilution of histamine could be performed in all patients without significant side effects. The geometric mean${\pm}$standard deviation of histamine PC20 in healthy volunteers is $8.27{\pm}2.22mg/ml$, BA group $0.33{\pm}3.02mg/ml$, RH group $0.85{\pm}3.24mg/ml$, and URI group $1.47{\pm}1.98mg/ml$. Conclusion: Histamine bronchial provocation test using timed tidal breath method is a simple and suitable tool for management of patients with bronchial hyperreactivity.

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Assessment of climate change impact on aquatic ecology health indices in Han river basin using SWAT and random forest (SWAT 및 random forest를 이용한 기후변화에 따른 한강유역의 수생태계 건강성 지수 영향 평가)

  • Woo, So Young;Jung, Chung Gil;Kim, Jin Uk;Kim, Seong Joon
    • Journal of Korea Water Resources Association
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    • v.51 no.10
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    • pp.863-874
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    • 2018
  • The purpose of this study is to evaluate the future climate change impact on stream aquatic ecology health of Han River watershed ($34,148km^2$) using SWAT (Soil and Water Assessment Tool) and random forest. The 8 years (2008~2015) spring (April to June) Aquatic ecology Health Indices (AHI) such as Trophic Diatom Index (TDI), Benthic Macroinvertebrate Index (BMI) and Fish Assessment Index (FAI) scored (0~100) and graded (A~E) by NIER (National Institute of Environmental Research) were used. The 8 years NIER indices with the water quality (T-N, $NH_4$, $NO_3$, T-P, $PO_4$) showed that the deviation of AHI score is large when the concentration of water quality is low, and AHI score had negative correlation when the concentration is high. By using random forest, one of the Machine Learning techniques for classification analysis, the classification results for the 3 indices grade showed that all of precision, recall, and f1-score were above 0.81. The future SWAT hydrology and water quality results under HadGEM3-RA RCP 4.5 and 8.5 scenarios of Korea Meteorological Administration (KMA) showed that the future nitrogen-related water quality in watershed average increased up to 43.2% by the baseflow increase effect and the phosphorus-related water quality decreased up to 18.9% by the surface runoff decrease effect. The future FAI and BMI showed a little better Index grade while the future TDI showed a little worse index grade. We can infer that the future TDI is more sensitive to nitrogen-related water quality and the future FAI and BMI are responded to phosphorus-related water quality.

Development of A Teaching-Learning Plan for Home Economics Education by Integrated Thematic Instruction(ITI) type (주제 중심 통합(ITI: Integrated Thematic Instruction)형 가정과 의생활영역 교수-학습 과정안 개발)

  • Kim, Nam Eun
    • Journal of Korean Home Economics Education Association
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    • v.29 no.3
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    • pp.141-160
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    • 2017
  • At present, the whole world is characterized by openness, cooperation and integration as a society with information and the world, and it requires creative talents for this. The competitiveness of the nation depends on the cultivation of creative talents. It demands anthropological value by improving the competitiveness of the nation through cultivating creative talents to share and care, not to cultivate creative talents for personal desires and accomplishments. The purpose of this study is to develop a teaching - learning process to develop integrated creative talents by applying the characteristics of integrated education curriculum at the base of the 2015 revised curriculum. To do this, we first extracted the content elements of the Clothing Life area of the revised curriculum from the 1st to 2015 and the contents of the Clothing Life area of the technology and home Economics textbooks to which the 2009 revision curriculum was applied. Five topics were extracted according to content selection criteria And The Theme of 'The selection and management of clothing' was selected. Researcher developed a integrated thematic instruction Home Economics Education Clothing Life teaching - learning process (hereinafter referred to as "the process") focused on the theme of 'selection and management of clothing'. The Process was composed of 5 basic classes [basic inquiry - content 1 - content 2 - depth study - application]. The process considers integration within the curriculum and interdepartmental integration, and aims to improve the personality, creativity, and problem solving ability of consideration and sharing in the course of the integrated class. In detail, the curriculum goals of the home Economics Education curriculum and ITI goals are presented separately in the curriculum developed for each process. At the stage of the class, the element of creativity and the element of personal education were exposed and applied to the class. In Korea, new curriculum has been revised and announced from time to time, making it difficult for the teacher to carry out the class in accordance with the paradigm of change. Home curriculum is closely related to real life, so it is an appropriate subject for an integrated subject. It has the educational significance of the subject in that it allows students to integrate the creative and personal elements that are limited in other subjects. ITI process will be helpful to teachers who need to implement the 2015 revised curriculum in which the theme-centered integrated home Economics education teaching-learning process is newly introduced. It is necessary to follow - up research to verify the effectiveness of how to improve students' problem - solving ability and cultivate creativity.