• Title/Summary/Keyword: component model

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The Effects of d-Amphetamine on the Brain 5-HT, 5-HIAA, MAO and the Behavior of Rat (d-Amphetamine이 백서뇌의 5-HT, 5-HIAA, MAO 및 행동에 미치는 영향에 관한 연구)

  • Suh, Yoo-Hun;Woo, Jong-In;Park, Chan-Woong
    • The Korean Journal of Pharmacology
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    • v.17 no.2
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    • pp.47-62
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    • 1981
  • d-amphetamine이 사람에서 paranoid schizophrenia와 아주 유사한 model psychosis를 일으키며 또한 사람과 실험동물에서 실제 정신분열증에서 뚜렷이 관찰되는 behavioral perservation을 일으킬 수 있음이 관찰되었다. 이에 많은 학자들은 이러한 양상의 행동변화가 정신분열증의 원인 추구에 중요한 의미를 주는 뇌변화를 반영할지도 모른다는 생각에 많은 연구를 거듭하여 왔다. 지금까지는 주로 catecholamine기전에 대하여 집중적 연구가 수행되어져 왔으나 최근에는 d-amphetamine의 약리기전의 일부는 5-HT기전이 차지하고 있으며, 여러 행동변화에는 catecholaimin 보다 5-HT 가 더 중요하게 관계하고 있다는 주장이 나오고 있다. 또한 d-amphetamine은 시험관내에서 MAO 특히 신경전달물질 분해요소인 A type를 가역적으로 억제할 수 있음이 보고되어 많은 흥미를 끌어왔으나 생체내에서의 억제여부는 직접적으로 확인이 되고 있지 않다. 그러나 최근에 Braestrup(1977)과 El Hait(1978)등은 간접적인 방법으로 생체내에서도 억제시킬 수 있음을 보고하고 있다. 이에 저자는 d-amphetamine에 의해 야기되는 행동변화와 그 밑바탕을 이루는 생화학적 기전에 5-HT가 차지하는 역할을 알아보기 위해서 다음의 실험을 시행하였다. 첫째, d-amphetamine의 급성, 만성 투여가 5-HT의 5-HIAA 로의 turnover와 MAO활성도에 어떤 영향을 미치며, 더 나아가서 이 양자사이에 어느 정도 상관관계가 있는지를 알아보기 위해서 d-amphetamine을 투여한 후 시간 경과에 따라서 뇌내 5-HT, 5-HIAA, 5-HT turnover rate와 MAO 활성도를 측정하였다. 둘째, d-amphetamine, 5-HT 합성을 증가시키는 약물과 합성을 억제시키는 약물을 투여하고, 위의 생화학적 실험과 행동관찰을 병합 실시하여 비교분석하였다. 그 결과는 다음과 같다. 1) d-amphetamine (6 mg/kg)을 급성투여시, 뇌내 5-HT함량이 투여 1시간 후에 최고로(대조치의 123%, p<0.001) 증가되다가 이후 감소하며, 5-HIAA 함량은 처음 15분부터 감소하기 시작하다가 30분에 최저로 떨어지며(대조치의 78%, p<0.005) 이후 증가하여 24시간째는 약간 대조치 이상으로 회복되었다. 미토콘드리아 MAO활성도는 1시간째에 최저로 떨어지다가(대조치의 89%, p<0.05)이후 회복하기 시작하여 24시간째에 약간 대조치 이상으로 회복되었다. 5-HT의 turnover rate는 MAO활성도 변화와 거의 같은 변화를 보였다. 2) 만성투여시 (하루 2번, 14일간 투여)는 5-HT 함량, 5-HIAA 함량, MAO 활성도 및 5-HT turnover rate 모두가 중등도로 감소되었다. (각각 대조치의 87%, 69%, 80%, 79%). 3) MAO 활성도와 5-HT turnover rate 사이에는 높은 상관관계가 있었다. (r=0.866, p<0.001, N=94). 4) MAO 활성도의 역동학 실험에서는 대조치에 비해 투여군에서 Km 값은 의미가 있는 증가가 있었으나 $V_{max}$값은 큰 변동이 없었다. 5) d-amphetamine을 급성 투여할때는 sleeping과 lying components는 상당한 감소를 보인 반면, locomotor activity 는 1시간까지는 상당한 증가를 보였으며 용량이 적을수록 더 큰 증가가 있었다. 반면 stereotypy는 1시간까지 용량이 증가할수록 더 큰 증가가 나타나서 locomotor activity에서 stereotypy 의 증가로 이행을 나타내었다. 만성 투여시는 locomotor activity는 점차적인 감소를 보였으나 stereotypy는 점차적인 증가가 나타나서 14일쯤에는 평형에 도달하였다. 6) PCPA 단독 투여군(400 mg/kg, 3번)에 있어서는 5-HT와 5-HIAA 함량의 상당한 감소가 나타났으나 MAO 활성도와 행동에는 큰 변화를 나타내지 않았다. PCPA전 처치군에 있어서도 5-HT와 5-HIAA 함량은 마찬가지로 상당한 감소를 나타내었으나 gnawing, sniffing과 locomotor activity는 더 증가를, stereotyped head weaving, forepaw treading과 hindlimb abduction은 상당한 감소를 나타내었다. 7) L-tryptophan(100 mg/kg)단독 투여시는 5-HT 함량은 약간 증가를 나타내었으나 5-HIAA 함량은 상당한 증가를 보였다. MAO활성도나 행동은 큰 변화없었다. L-tryptophan 전처치군에 있어서는 5-HT 함량은 더 큰 증가를 보였으나, 5-HIaa 함량은 MAO 활성도는 별 변화없었으며 stereotypedlateral head waving, forepaw treading 과 hindlimb abduction은 증가를, locomotor activity, gnawing과 sniffing components는 감소를 나타내었다. 8) d-amphetamine 단독투여, 혹은 L-tryptophan 전처치, PCPA 전처치후 측정한 5-HT 함량과 stereotyped head weaving, forepaw treading, hinilimb abduction components 사이에는 높은 상관관계가 있었다(r=0.789, p<0.001). 반면 5-HT 함량과 locomotor activity, stereotyped gnawing과 sniffing components 사이에는 약한 음성의 상관관계가 있었다. (r=0.554, p <0.005). 이상의 결과로 미루어 볼때 5-HT의 5-HIAA 로의 turnover rate 는 주로 MAO 활성도에 의해서 조절되며 5-HT 기전이 d-amphetamine에 의해서 야기된 여러 행동변화 중 상당한 부분에서 중요한 역할을 하리라고 생각된다.

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A Study on Clinical Variables Contributing to Differentiation of Delirium and Non-Delirium Patients in the ICU (중환자실 섬망 환자와 비섬망 환자 구분에 기여하는 임상 지표에 관한 연구)

  • Ko, Chanyoung;Kim, Jae-Jin;Cho, Dongrae;Oh, Jooyoung;Park, Jin Young
    • Korean Journal of Psychosomatic Medicine
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    • v.27 no.2
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    • pp.101-110
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    • 2019
  • Objectives : It is not clear which clinical variables are most closely associated with delirium in the Intensive Care Unit (ICU). By comparing clinical data of ICU delirium and non-delirium patients, we sought to identify variables that most effectively differentiate delirium from non-delirium. Methods : Medical records of 6,386 ICU patients were reviewed. Random Subset Feature Selection and Principal Component Analysis were utilized to select a set of clinical variables with the highest discriminatory capacity. Statistical analyses were employed to determine the separation capacity of two models-one using just the selected few clinical variables and the other using all clinical variables associated with delirium. Results : There was a significant difference between delirium and non-delirium individuals across 32 clinical variables. Richmond Agitation Sedation Scale (RASS), urinary catheterization, vascular catheterization, Hamilton Anxiety Rating Scale (HAM-A), Blood urea nitrogen, and Acute Physiology and Chronic Health Examination II most effectively differentiated delirium from non-delirium. Multivariable logistic regression analysis showed that, with the exception of vascular catheterization, these clinical variables were independent risk factors associated with delirium. Separation capacity of the logistic regression model using just 6 clinical variables was measured with Receiver Operating Characteristic curve, with Area Under the Curve (AUC) of 0.818. Same analyses were performed using all 32 clinical variables;the AUC was 0.881, denoting a very high separation capacity. Conclusions : The six aforementioned variables most effectively separate delirium from non-delirium. This highlights the importance of close monitoring of patients who received invasive medical procedures and were rated with very low RASS and HAM-A scores.

Anti-inflammatory Effects of Purpurogallin Carboxylic Acid, An Oxidation Product of Gallic Acid in Fermented Tea (발효차중의 미량 성분인 gallic acid 산화물 purpurogallin carboxylic acid의 항염증 효과)

  • Jhoo, Jin-Woo
    • Korean Journal of Food Science and Technology
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    • v.40 no.6
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    • pp.707-711
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    • 2008
  • The principal objective of the current study was to isolate a purpurogallin derivative as an oxidation product from gallic acid, in an effort to assess the anti-inflammatory effects of this compound. Purpurogallin derivative is known to be the one of the oxidation products of gallic acid. This compound has been identified as a minor chemical component in fermented tea products. It has been previously demonstrated that theaflavins, the oxidation products of catechins found in fermented tea products, exert profound antioxidant and anti-inflammatory effects. However, the biological activities of a minor chemical component in fermented teas have yet to be evaluated. Purpurogallin carboxylic acid (PCA) was identified as a major oxidation product of gallic acid from a peroxidase/hydrogen peroxide oxidation model system. The identity of the PCA was verified by $^{1}H$ NMR, $^{13}C$ NMR and MS techniques. PCA treatment significantly suppressed the generation of pro-inflammatory mediators including nitric oxide and IL-6 in lipopolysaccharide (LPS)-stimulated RAW264.7 murine macrophages. According to the nitrite assay, PCA 100, 75, and $50{\mu}g/mL$ treatment dose-dependently inhibited NO production by 57.6, 41.5, and 21.8%, respectively, in LPS-stimulated RAW264.7 murine macrophage cells. Moreover, IL-6 production was inhibited to a significant degree with PCA treatment of 100 and $75{\mu}g/mL$ at 43.1 and 23.9%, respectively. PCA treatment also significantly suppressed $PGE_2$ production at levels of 100 and $75{\mu}g/mL$. These results showed that PCA exerts inhibitory effects on the production of inflammatory mediators.

Studies on the Therapeutic Effect and Mechanism of Korean Red Ginseng Total Saponin on Infertility Caused by Polycystic Ovaries (홍삼사포닌 투여의 다낭성난소에 의한 불임 치료효과 및 기작연구)

  • Kim, Se-Eun;Oh, Dong-Min;Sim, Kyung-Mi;Jeong, Moon-Jin;Lim, Sung-Chul;Nah, Seung-Yeol;Lee, Yun-Lyul;Kang, Seong-Soo;Moon, Chang-Jong;Kim, Jong-Choon;Kim, Sung-Ho;Bae, Chun-Sik
    • Applied Microscopy
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    • v.39 no.1
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    • pp.1-7
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    • 2009
  • Experimental induction of polycystic ovary (PCO) resembling some aspects of human PCO syndrome was produced using the long-acting compound estradiol valerate (EV). Our previous study on the role of Korean red ginseng total saponins (GTS) in a steroid-induced PCO rat model demonstrated that electro-acupuncture modulates nerve growth factor (NGF) concentration in the ovaries. In fact, the involvement of a neurogenic component in the pathology of PCO-related ovarian dysfunction is preceded by an increase in sympathetic outflow to the ovaries. In the present study, we tested the hypothesis that therapeutic GTS administration modulates sympathetic nerve activity in rats with PCO. This was done by analyzing NGF protein and NGF mRNA expression involved in the pathophysiological process underlying steroid-induced PCO. EV injection resulted in significantly higher ovarian NGF mRNA expression in PCO rats compared to control rats, and PCO ovaries were counteracted by GTS administration with significantly lower expression of NGF mRNA compared to EV treated ovaries. However, NGF protein was unaffected in both EV and GTS treated ovaries compared to control rats. These results indicate that EV modulates the neurotrophic state of the ovaries, which may be a component of the pathological process by which EV induces cyst formation and anovulation in rodents.

Gadolinium-Enhanced Magnetic Resonance Imaging of Atherosclerotic Plaques in Comparison with Histopathology: An In Vivo Study in Aorta of Rabbits (조직병리와 비교한 죽상경화반의 가돌리니움 조영증강 자기공명영상: 토끼 대동맥을 이용한 생체 실험)

  • Choi, Byoung-Wook;Hur, Jin;Lee, Hye-Jeong;Kim, Young-Jin;Kim, Tae-Hoon;Choe, Kyu-Ok
    • Investigative Magnetic Resonance Imaging
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    • v.13 no.1
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    • pp.81-87
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    • 2009
  • Purpose : We sought to evaluate enhancement of plaque with gadolinium-based contrast agent by magnetic resonance imaging (MRI) in comparison with histopathology, namely lipid-rich and macrophage-rich components that were two representative characteristics of plaque vulnerability using atherosclerotic rabbit aorta in order to determine which histopathologic component is relevant to the enhancement. Materials and Methods : New Zealand white rabbit (n=4, weight 3.0 to 3.5 kg, all male) was used for animal model of atherosclerosis. Atherosclerotic aortic lesions were induced by high-cholesterol diet and double balloon injury. T1-weight axial images were acquired before and after gadolinium-based contrast agent using a 3-T MRI. MR images and the matched histopathological sections (n=35) were divided into 4 quadrants or 3 (n=130). Enhancement ratio (ER, ER=SIpost/SIpre) on MRI was calculated for each quadrant and compared with histopathology in regard to lipid-rich and macrophage-rich areas. Results : Lipid-rich quadrants were 72 and fibrous quadrants were 58. The number of quadrants which had macrophage-rich areas was 105 and that of quadrants which did not have macrophage-rich areas was 25. ER was significantly higher in lipid-rich quadrants than in fibrous quadrants (mean ER 2.25c$\pm$0.41 vs. 2.72$\pm$0.65, p=0.013). ER poorly correlated with macrophage-rich areas when lipid-component was controlled (correlation coefficient -0.203, p=0.236). Conclusion : Lipid-rich plaques showed stronger enhancement than fibrous plaques using a standard gadolinium-based extracellular contrast agent. Macrophage infiltration did not correlate with degree of enhancement. Further study is warranted that account for optimal time of imaging after contrast injection using various plaque models from early to advanced stages and all possible parameters associated with contrast enhancement.

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A Development of Automatic Lineament Extraction Algorithm from Landsat TM images for Geological Applications (지질학적 활용을 위한 Landsat TM 자료의 자동화된 선구조 추출 알고리즘의 개발)

  • 원중선;김상완;민경덕;이영훈
    • Korean Journal of Remote Sensing
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    • v.14 no.2
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    • pp.175-195
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    • 1998
  • Automatic lineament extraction algorithms had been developed by various researches for geological purpose using remotely sensed data. However, most of them are designed for a certain topographic model, for instance rugged mountainous region or flat basin. Most of common topographic characteristic in Korea is a mountainous region along with alluvial plain, and consequently it is difficult to apply previous algorithms directly to this area. A new algorithm of automatic lineament extraction from remotely sensed images is developed in this study specifically for geological applications. An algorithm, named as DSTA(Dynamic Segment Tracing Algorithm), is developed to produce binary image composed of linear component and non-linear component. The proposed algorithm effectively reduces the look direction bias associated with sun's azimuth angle and the noise in the low contrast region by utilizing a dynamic sub window. This algorithm can successfully accomodate lineaments in the alluvial plain as well as mountainous region. Two additional algorithms for estimating the individual lineament vector, named as ALEHHT(Automatic Lineament Extraction by Hierarchical Hough Transform) and ALEGHT(Automatic Lineament Extraction by Generalized Hough Transform) which are merging operation steps through the Hierarchical Hough transform and Generalized Hough transform respectively, are also developed to generate geological lineaments. The merging operation proposed in this study is consisted of three parameters: the angle between two lines($\delta$$\beta$), the perpendicular distance($(d_ij)$), and the distance between midpoints of lines(dn). The test result of the developed algorithm using Landsat TM image demonstrates that lineaments in alluvial plain as well as in rugged mountain is extremely well extracted. Even the lineaments parallel to sun's azimuth angle are also well detected by this approach. Further study is, however, required to accommodate the effect of quantization interval(droh) parameter in ALEGHT for optimization.

Construction and Application of Intelligent Decision Support System through Defense Ontology - Application example of Air Force Logistics Situation Management System (국방 온톨로지를 통한 지능형 의사결정지원시스템 구축 및 활용 - 공군 군수상황관리체계 적용 사례)

  • Jo, Wongi;Kim, Hak-Jin
    • Journal of Intelligence and Information Systems
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    • v.25 no.2
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    • pp.77-97
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    • 2019
  • The large amount of data that emerges from the initial connection environment of the Fourth Industrial Revolution is a major factor that distinguishes the Fourth Industrial Revolution from the existing production environment. This environment has two-sided features that allow it to produce data while using it. And the data produced so produces another value. Due to the massive scale of data, future information systems need to process more data in terms of quantities than existing information systems. In addition, in terms of quality, only a large amount of data, Ability is required. In a small-scale information system, it is possible for a person to accurately understand the system and obtain the necessary information, but in a variety of complex systems where it is difficult to understand the system accurately, it becomes increasingly difficult to acquire the desired information. In other words, more accurate processing of large amounts of data has become a basic condition for future information systems. This problem related to the efficient performance of the information system can be solved by building a semantic web which enables various information processing by expressing the collected data as an ontology that can be understood by not only people but also computers. For example, as in most other organizations, IT has been introduced in the military, and most of the work has been done through information systems. Currently, most of the work is done through information systems. As existing systems contain increasingly large amounts of data, efforts are needed to make the system easier to use through its data utilization. An ontology-based system has a large data semantic network through connection with other systems, and has a wide range of databases that can be utilized, and has the advantage of searching more precisely and quickly through relationships between predefined concepts. In this paper, we propose a defense ontology as a method for effective data management and decision support. In order to judge the applicability and effectiveness of the actual system, we reconstructed the existing air force munitions situation management system as an ontology based system. It is a system constructed to strengthen management and control of logistics situation of commanders and practitioners by providing real - time information on maintenance and distribution situation as it becomes difficult to use complicated logistics information system with large amount of data. Although it is a method to take pre-specified necessary information from the existing logistics system and display it as a web page, it is also difficult to confirm this system except for a few specified items in advance, and it is also time-consuming to extend the additional function if necessary And it is a system composed of category type without search function. Therefore, it has a disadvantage that it can be easily utilized only when the system is well known as in the existing system. The ontology-based logistics situation management system is designed to provide the intuitive visualization of the complex information of the existing logistics information system through the ontology. In order to construct the logistics situation management system through the ontology, And the useful functions such as performance - based logistics support contract management and component dictionary are further identified and included in the ontology. In order to confirm whether the constructed ontology can be used for decision support, it is necessary to implement a meaningful analysis function such as calculation of the utilization rate of the aircraft, inquiry about performance-based military contract. Especially, in contrast to building ontology database in ontology study in the past, in this study, time series data which change value according to time such as the state of aircraft by date are constructed by ontology, and through the constructed ontology, It is confirmed that it is possible to calculate the utilization rate based on various criteria as well as the computable utilization rate. In addition, the data related to performance-based logistics contracts introduced as a new maintenance method of aircraft and other munitions can be inquired into various contents, and it is easy to calculate performance indexes used in performance-based logistics contract through reasoning and functions. Of course, we propose a new performance index that complements the limitations of the currently applied performance indicators, and calculate it through the ontology, confirming the possibility of using the constructed ontology. Finally, it is possible to calculate the failure rate or reliability of each component, including MTBF data of the selected fault-tolerant item based on the actual part consumption performance. The reliability of the mission and the reliability of the system are calculated. In order to confirm the usability of the constructed ontology-based logistics situation management system, the proposed system through the Technology Acceptance Model (TAM), which is a representative model for measuring the acceptability of the technology, is more useful and convenient than the existing system.

Temperature-dependent Development and Fecundity of Rhopalosiphum padi (L.) (Hemiptera: Aphididae) on Corns (옥수수에서 기장테두리진딧물의 온도 의존적 발육과 산자 특성)

  • Park, Jeong Hoon;Kwon, Soon Hwa;Kim, Tae Ok;Oh, Sung Oh;Kim, Dong-Soon
    • Korean journal of applied entomology
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    • v.55 no.2
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    • pp.149-160
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    • 2016
  • Temperature-dependent development and fecundity of apterious Rhopalosiphum padi (L.) (Hemiptera: Aphididae) were examined at six constant temperatures (10, 15, 20, 25, 30 and $35{\pm}1.0^{\circ}C$, RH 50-70%, 16L:8D). Development time of nymphs decreased with increasing temperature and ranged from 42.9 days at $10^{\circ}C$ to 4.7 days at $30^{\circ}C$. The nymphs did not develop until adult at $35^{\circ}C$ because the nymphs died during the 2nd instar. The lower threshold temperature and thermal constant of nymph were estimated as $8.3^{\circ}C$ and 101.6 degree days, respectively. The relationships between development rates of nymph and temperatures were well described by the nonlinear model of Lactin 2. The distribution of development times of each stage was successfully fitted to the Weibull function. The longevity of apterious adults decreased with increasing temperature ranging from 24.0 days at $15^{\circ}C$ to 4.3 days at $30^{\circ}C$, with abnormally short longevity of 11.1 days at $10^{\circ}C$. R. padi showed the highest fecundity at $20^{\circ}C$ (38.2) and the lowest fecundity at $10^{\circ}C$ (3.9). In this study, we provided component sub-models for the oviposition model of R. padi: total fecundity, age-specific cumulative oviposition rate, and age-specific survival rate as well as adult aging rate based on the adult physiological age.

Comparison of Algorithms for Generating Parametric Image of Cerebral Blood Flow Using ${H_2}^{15}O$ PET Positron Emission Tomography (${H_2}^{15}O$ PET을 이용한 뇌혈류 파라메트릭 영상 구성을 위한 알고리즘 비교)

  • Lee, Jae-Sung;Lee, Dong-Soo;Park, Kwang-Suk;Chung, June-Key;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
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    • v.37 no.5
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    • pp.288-300
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    • 2003
  • Purpose: To obtain regional blood flow and tissue-blood partition coefficient with time-activity curves from ${H_2}^{15}O$ PET, fitting of some parameters in the Kety model is conventionally accomplished by nonlinear least squares (NLS) analysis. However, NLS requires considerable compuation time then is impractical for pixel-by-pixel analysis to generate parametric images of these parameters. In this study, we investigated several fast parameter estimation methods for the parametric image generation and compared their statistical reliability and computational efficiency. Materials and Methods: These methods included linear least squres (LLS), linear weighted least squares (LWLS), linear generalized least squares (GLS), linear generalized weighted least squares (GWLS), weighted Integration (WI), and model-based clustering method (CAKS). ${H_2}^{15}O$ dynamic brain PET with Poisson noise component was simulated using numerical Zubal brain phantom. Error and bias in the estimation of rCBF and partition coefficient, and computation time in various noise environments was estimated and compared. In audition, parametric images from ${H_2}^{15}O$ dynamic brain PET data peformed on 16 healthy volunteers under various physiological conditions was compared to examine the utility of these methods for real human data. Results: These fast algorithms produced parametric images with similar image qualify and statistical reliability. When CAKS and LLS methods were used combinedly, computation time was significantly reduced and less than 30 seconds for $128{\times}128{\times}46$ images on Pentium III processor. Conclusion: Parametric images of rCBF and partition coefficient with good statistical properties can be generated with short computation time which is acceptable in clinical situation.

A FEM comparison study about the force, displacement and initial stress distribution on the maxillary first molars by the application of Asymmetric Head-Gears with the different traction forces (Asymmetric Head-Gear의 견인력의 차이에 따른 상악 제 1 대구치에 나타나는 힘과 변위 및 초기 응력분포에 관한 유한요소법적 비교 연구)

  • Cha, Kyung-Suk
    • The korean journal of orthodontics
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    • v.31 no.3 s.86
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    • pp.311-323
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    • 2001
  • One of the various mechanics used to treat unilateral Class II malocclusion is head gear with asymmetric face bow. We made the finite element models of unilateral Class II maxillary dental arch and power arm asymmetric face bow. We designed this experiment to observe stress distribution of periodontal ligament, reaction force, and displacement and to understand force system, so to predict the therapeutic effect. On the basis of computerized tomograph of maxillary dental arch of 25 years old male with normal occlusion without extraction and orthodontic treatment history, we made finite element models of maxillary dental arch and periodontal ligament. Then we modified that model to unilateral maxillary Class II malocclusion model of which maxillary left molar displaced mesially. Also, We made finite element model of asymmetric face bow of which right outer bow shorter than left by 25mm(RMO, Penta-FormTM/Medium size, 0.045 inch iner bow, 0.072 inch outer bow). After that, retraction force of 250g, 300b, 350g were applied to maxillary first molar. We concluded as follow. 1. The Net force that both maxillary first molars were received increased as the retraction force increased. Mesially positioned tooth received more force than normally positioned tooth. But, both tooth were received distal force, so distal movement occured. 2. Both tooth received buccal lateral force. In analysis of force element, as the retraction force were increased, force of X-axis at mesially positioned tooth decreased, and force of X-axis at normally positioned tooth increased. so lateral force component moved to the side received less force from more force. 3. There were rotation, tipping with distal movement in maxillary first molar. As retraction force were increased, rotation and tipping also increased. More tipping and rotation occured at the side received more force, that is, mesially positioned tooth. Though it Is small change, displacement of same pattern occur in normally positioned tooth

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