• Title/Summary/Keyword: ST-segments

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Developmental and Environmental Sources of Variation on Annual Growth Increments of Ascophyllum nodosum (Phaeophyceae)

  • Eckersley, Lindsay K.;Garbary, David J.
    • ALGAE
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    • v.22 no.2
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    • pp.107-116
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    • 2007
  • Annual growth segments of Ascophyllum nodosum (L.) Le Jolis (Fucales, Fucaceae) are denoted by air bladders that form each spring. By examining annual growth segments, it may be possible to infer information about the physical conditions during the growth period; however, it is uncertain whether the annual segments will expand in size after the initial growth. We examined A. nodosum segments from three populations in Nova Scotia, and statistically evaluated whether the annual growth (length, mass, and maximum diameter) of segments was independent of the age of the frond, whether the segments increased in size after the initial growth, and whether the segment lengths were correlated with mean water temperatures and mean air temperatures when the segments were formed. We found that the growth in length of A. nodosum is dependent on the age of the frond, but frond age explained less than 12 % of the overall variation in length. However, the mass and maximum diameter of segments were independent of the age of the frond. Differences occurred between the lengths of segments formed in different years, but there was no significant correlation with regional mean water or air temperatures. This study indicates that the length of A. nodosum segments may be an indicator of the annual physical characteristics of a site, but future studies are needed to identify which factors have the strongest influence on growth patterns.

Enhancement of ST-segment Features in ECG Signals by Warping Transformation (워핑 변환을 이용한 심전도 신호의 ST 분절 특징 값 강화)

  • Shin, Seung-Won;Kim, Kyeong-Seop
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.6
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    • pp.1143-1149
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    • 2010
  • In this study, we propose a novel method to detect and enhance the feature of ST-segment which offers the crucial information for the diagnosis of myocardial infarction and ischemia. With this aim, PQRST features of Electrocardiogram initially are detected and subsequently ST-segment are estimated. And Dynamic Time Warping(DTW) transformation is applied recursively to minimize the difference in time between ST-segments and calculate the minimum cumulative distance that decides the degree of similarity among ST-segments. As of the results, the inherent characteristic of ST-segment can be emphasized in terms of time parameter and thus the diagnostic features of a ST-segment can be revealed further.

XML Document Filtering based on Segments (세그먼트 기반의 XML 문서 필터링)

  • Kwon, Joon-Ho;Rao, Praveen;Moon, Bong-Ki;Lee, Suk-Ho
    • Journal of KIISE:Databases
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    • v.35 no.4
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    • pp.368-378
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    • 2008
  • In recent years, publish-subscribe (pub-sub) systems based on XML document filtering have received much attention. In a typical pub-sub system, subscribed users specify their interest in profiles expressed in the XPath language, and each new content is matched against the user profiles so that the content is delivered to only the interested subscribers. As the number of subscribed users and their profiles can grow very large, the scalability of the system is critical to the success of pub-sub services. In this paper, we propose a fast and scalable XML filtering system called SFiST which is an extension of the FiST system. Sharable segments are extracted from twig patterns and stored into the hash-based Segment Table in SFiST system. Segments are used to represent user profiles as Terse Sequences and stored in the Compact Segment Index during filtering. Our experimental study shows that SFiST system has better performance than FiST system in terms of filtering time and memory usage.

An efficient recognition of round objects using the curve segment grouping (곡선 조각의 군집화에 의한 둥근 물체의 효과적인 인식)

  • 성효경;최흥문
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.34C no.9
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    • pp.77-83
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    • 1997
  • Based on the curve segment grouping, an efficient recognition of round objects form partially occuluded round boundaries is proposed. Curve segments are extracted from an image using a criterion based on the intra-segment curvature and local contrast. During the curve segment extraction the boundaries of pratially occluding and occuluded objects are segmented to different curve segments. The extracted segments of constant intra-segment curvature are grouped to different curve segments. The extracted segments of constant intra-segment curvature are grouped nto a round boundary by the proposed grouping algorithm using inter-segment curvature which gives the relatinships among the curve segments of the same round boundary. The 1st and the 2nd order moments are used for the parameter estimation of the best fitted ellipse with round boundary, and then recognition is perfomed based on the estimated parameters. The proposed scheme processes in segment unit and is more efficient in computational complexity and memory requirements those that of the conventional scheme which processed in pixel units. Experimental results show that the proposed technique is very efficient in recognizing the round object sfrom the real images with apples and pumpkins.

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Transient Prolonged Stunning by Dipyridamole Stress Proved by Post-stress(1 hour) and 24 hour Tc-99m-MIBI Gated SPECT (반복 게이트 심근 Tc-99m-MIBI SPECT로 확인한 디피리다몰 부하에 의한 일과성 심근기절현상)

  • Lee, Dong-Soo;Yoon, Seok-Nam;Lee, Won-Woo;Chung, June-Key;Lee, Myoung-Mook;Lee, Myung-Chul;Koh, Chang-Soon
    • The Korean Journal of Nuclear Medicine
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    • v.31 no.1
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    • pp.57-66
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    • 1997
  • We performed 1st day Tc-99m-sestamibi gated SPECT with dipyridamole/rest T1-201 SPECT and 2nd day 24 hour delay T1-201 SPECT/rest Tc-99m-sestamibi gated SPECT in 27 patients with coronary artery disease(24) or having chest pain(3). Stress and rest Tc-99m-sestamibi gated SPECT was acquired at 60min post-injection. A 4-point scoring system(0 to 3 for normal to absent tracer uptake) for 17 segments was used. Wall motion was scored on another 4 point scale(0 to 3 for normal to dyskinesia) in the 1st day post-stress gated and the 2nd day rest gated SPECT. Post-stress gated SPECT showed wall motion abnormality in 94 segments(20%). Fifty-five segments among these 94 showed the same wall motion between post-stress and rest gated SPECT: i.e. 1-1 23 segments, 2-2: 29 segments, 3-3: 3 segments. Remaining 39 segments(41.5%) showed different wall motion between post- stress and rest Tc-99m-sestamibi gated SPECT. Twenty one segments with wall motion abnormality had normal perfusion(rest : 15 segments, 24 hour delay: 6 segments) at either rest or 24 hour delay. Fifteen among these 21 segments showed persistent post-stress and the 2nd day rest wall motion abnormality(persistent stunning). However, in 6 segments with pro-longed (1 hour after stress) stunning, abnormal wall motion did improve in the 2nd day rest Tc-99m-sestamibi gated SPECT(transient prolonged stunning). These 6 segments had normal perfusion at rest(n=4) or at 24 hour delay(n=2). Post stress wall motions showed significantly higher scores in persistent stunning than in prolonged transient stunning(P value<0.05). It was concluded that we could find stunned myocardium with gated Tc-99m-sestamibi SPECT at either post-stress or rest and that some myocardial walls of post-stress 1 hour gated SPECT did not show truly rest wall motion. So, we should be cautious if we use post-stress Tc-99m-sestamibi wall motion to assess rest wall motion.

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Radiomics of Non-Contrast-Enhanced T1 Mapping: Diagnostic and Predictive Performance for Myocardial Injury in Acute ST-Segment-Elevation Myocardial Infarction

  • Quanmei Ma;Yue Ma;Tongtong Yu;Zhaoqing Sun;Yang Hou
    • Korean Journal of Radiology
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    • v.22 no.4
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    • pp.535-546
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    • 2021
  • Objective: To evaluate the feasibility of texture analysis on non-contrast-enhanced T1 maps of cardiac magnetic resonance (CMR) imaging for the diagnosis of myocardial injury in acute myocardial infarction (MI). Materials and Methods: This study included 68 patients (57 males and 11 females; mean age, 55.7 ± 10.5 years) with acute ST-segment-elevation MI who had undergone 3T CMR after a percutaneous coronary intervention. Forty patients of them also underwent a 6-month follow-up CMR. The CMR protocol included T2-weighted imaging, T1 mapping, rest first-pass perfusion, and late gadolinium enhancement. Radiomics features were extracted from the T1 maps using open-source software. Radiomics signatures were constructed with the selected strongest features to evaluate the myocardial injury severity and predict the recovery of left ventricular (LV) longitudinal systolic myocardial contractility. Results: A total of 1088 segments of the acute CMR images were analyzed; 103 (9.5%) segments showed microvascular obstruction (MVO), and 557 (51.2%) segments showed MI. A total of 640 segments were included in the 6-month follow-up analysis, of which 160 (25.0%) segments showed favorable recovery of LV longitudinal systolic myocardial contractility. Combined radiomics signature and T1 values resulted in a higher diagnostic performance for MVO compared to T1 values alone (area under the curve [AUC] in the training set; 0.88, 0.72, p = 0.031: AUC in the test set; 0.86, 0.71, p = 0.002). Combined radiomics signature and T1 values also provided a higher predictive value for LV longitudinal systolic myocardial contractility recovery compared to T1 values (AUC in the training set; 0.76, 0.55, p < 0.001: AUC in the test set; 0.77, 0.60, p < 0.001). Conclusion: The combination of radiomics of non-contrast-enhanced T1 mapping and T1 values could provide higher diagnostic accuracy for MVO. Radiomics also provides incremental value in the prediction of LV longitudinal systolic myocardial contractility at six months.

THE STATISTICAL STUDY OF INTERDENTAL SPACE IN THE PRIMARY DENTITION (유치열(乳齒列)의 치간공극(齒間空隙)에 관(關)한 통계학적(統計學的) 연구(硏究))

  • Ko, Chun-Suk
    • Journal of the korean academy of Pediatric Dentistry
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    • v.7 no.1
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    • pp.53-61
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    • 1980
  • The purpose of this study was to statistically evaluate the spacing of primary dentition according to whether or not a space existed and measurement of amount of space in 205 children (male 114, female 91) from 2 to 6 years of age. The results were as follows; 1. In the incidence of interdental space on each region, spacing between the primary lateral incisors and primary canine in maxilla and between the primary canine and 1st primary molar in mandible showed the highest percentage, on the other hand, spacing between the 1st and 2nd primary molars in both jaw showed the lowest percentage. 2. In the kinds of interdental space, the state of primate space and other space together showed the highest percentage, and in the degree of spacing, $S_2$ showed the highest percentage in both jaw. 3. In the incidence of primate space, maxillary primate space showed higher percentage than mandibular primate space in bilateral case. 4. In the type of arch form, spaced arch showed higher percentage than closed arch and about the half of closed arch showed crowding. 5. In both Jaw, available space showed incisor segments, canine segments, and premolar segments in order of amount, and there were not statistically significant differences of sex or jaws in the amount of available space.

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A Case of Anomalous Systemic Arterial Supply to Normal Basal Segments of Left Lower Lobe (좌하엽으로의 비정상적인 체순환 1예)

  • Kim, Jae Deok;Kim, Youn Seup;Lim, Hong Mok;Lee, Sang Rok;Lee, Kye Young
    • Tuberculosis and Respiratory Diseases
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    • v.56 no.1
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    • pp.97-102
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    • 2004
  • Anomalous systemic arterial supply to the lung is a rare congenital anomaly. The lung supplied by the anomalus systemic artery has a normal bronchial tree, which is usually in the basal segment of the lung, especially in the left lung. Most of patients are asymptomatic, but the main clinical symptoms of this disease are hemoptysis and exertional dyspnea. CT is useful for the diagnosis and showed a retrocardiac nodular shadow connected to the descending aorta branching into the basal segments of the relatively normal lower lobe. Surgery is indicated for all patients. Here we report a case of anomalous systemic arterial supply to normal basal segments of left lower lobe in a patient with hemoptysis with a review of the relevant literature.

The Efficacy and Perioperative Complications Associated with Lumbar Spinal Fusion Surgery, Focusing on Geriatric Patients in the Republic of Korea

  • Kim, Il-Chun;Hur, Jin-Woo;Kwon, Ki-Young;Lee, Jong-Ju;Lee, Jong-Won;Lee, Hyun-Koo
    • Journal of Korean Neurosurgical Society
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    • v.54 no.4
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    • pp.323-328
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    • 2013
  • Objective : The purpose of this study was to examine the efficacy and perioperative complications associated with lumbar spinal fusion surgery, focusing on geriatric patients in the Republic of Korea. Methods : We retrospectively investigated 485 patients with degenerative spinal diseases who had lumbar spinal fusion surgeries between March 2006 and December 2010 at our institution. Age, sex, comorbidity, American Society of Anesthesiologists (ASA) class, fusion segments, perioperative complications, and outcomes were analyzed in this study. Risk factors for complications and their association with age were analyzed. Results : In this study, 81 patients presented complications (16.7%). The rate of perioperative complications was significantly higher in patients 70 years or older than in other age groups (univariate analysis, p=0.015; multivariate analysis, p=0.024). The perioperative complications were not significantly associated with the other factors tested (sex, comorbidity, ASA class, and fusion segments). Post-operative outcomes of lumbar spinal fusion surgeries for the patients were determined on the basis of MacNab's criteria (average follow up period : 19.7 months), and 412 patients (85.0%) were classified as having "excellent" or "good" results. Conclusion : Increasing age was an important risk factor for perioperative complications in patients undergoing lumbar spinal fusion surgery, whereas other factors were not significant. However, patients' satisfaction or return to daily activities when compared with younger patients did not show much difference. We recommend good clinical judgment as well as careful selection of geriatric patients for lumbar spinal fusion surgery.

Realtime Wireless Monitoring of Abnormal ST in ECG Using PC Based System

  • Jeong, Gu-Young;Yu, Kee-Ho;Kim, Nam-Gyun;Inooka, Hikaru
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.176-180
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    • 2004
  • The ST-segment that the beginning part of T wave is the important diagnostic parameter to finding myocardial ischemia. Abnormal ST appears in two types. One is the level change, and the other is the pattern change. In this paper, we describe the monitoring of abnormal ST using PC based system. Hardware of this system consists of transmitter, receiver and PC. The function of transmitter is measuring ECG in three channels which are selected manually and transmitting the data to receiver by digital radio way. Connection with receiver and PC is by RS232C, and the data received on the PC is analyzed automatically by ECG analysis algorithm and saved to file. In the algorithm part for detecting abnormal ST, ST-segments are approximated by a polynomial. This method can detect all of the deviation and pattern change of ST-segment regardless the change in the heart rate or sampling rate. To gain algorithm reliability, the method rejects distorted polynomial approximation by calculation the difference between the approximated ST-segment and original ST-segment. In pre-signal processing, the wavelet transformation separates high frequency bands including QRS complex from the original ECG. Consequently, the process improves the performance of detecting each feature points.

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