• Title/Summary/Keyword: ICA

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Surgical Experience of Paraclinoidal Aneurysms (상상돌기 주위 동맥류의 수술적 치험)

  • Kang, Hyung Gon;Jo, Chul Min;Huh, Jae Teack
    • Journal of Korean Neurosurgical Society
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    • v.30 no.sup2
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    • pp.203-210
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    • 2001
  • Objective : Paraclinoidal aneurysms termed that aneurysms arising from proximal internal carotid artery(ICA) between the site of emergence of the carotid artery from roof of the cavernous sinus and origin of the posterior communicating artery(PCoA). These aneurysms pose conceptual and technical surgical problems with regard to acquisition of proximal control and safe intracranial exposure. The efficiency of surgical technique according to the location of paraclinoidal aneurysm was studied for minimal exposure. Materials and Methods : Over the past four years, the authors treated surgically 171 cases of cerebral aneurysm, among them ten patients were paraclinoidal aneurysms with two patients unruptured aneurysms. Mean age was 47 years old, and all patients were female. Three patients were proximal posterior carotid artery wall aneurysms(one large, one giant), four patients carotid-ophthalmic artery aneurysms and three patients superior hypophyseal artery aneurysms. Results : There could be done clip in all cases, there were no deaths and no complication. And no patient developed sustained neurological deficits including visual function except hydrocephalus in one case. Four patients complained of visual disturbance but two patients had recovery after postoperation and two patient were not longer to bad. Conclusion : Our recent experience suggests that preoperative scrutiny of diagnostic angiography allows classification of all paraclinoidal aneurysms regardless of size and surgical technique which this classification has focused on operative approaches unique to each aneurysm projection was helpful to improve the operative outcome with good visual function and to shorten the operative time.

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Transient Middle Cerebral Artery Occlusion Model in Mouse using Nylon Thread (Nylon Thread를 이용한 mouse 에서의 Transient middle cerebral artery occlusion (MCAO) model 확립)

  • Lim, Byung-Chul;Sung, Ji-Hee;Kim, Ha-Na;Park, Seoung-Woo
    • The Journal of the Korea Contents Association
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    • v.19 no.7
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    • pp.186-191
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    • 2019
  • Introduction: In aged people, stroke incidence is increased. But standardized experimental animal protocol study for the research of stroke therapy is rare. There is little report on the success rate of cerebral artery occlusion model using standardized Nylon thread length of precise thread end-size controlled. Method: In this study, the operator intended the occlusion of middle cerebral artery (MCA) using $0.18{\pm}0.02mm$ end 5-0 Nylon thread. Middle cerebral artery occlusion was induced for 60min under isoflurane anesthesia. After 60min, the operator removed the Nylon thread and reperfusion was induced for 23hrs. The mice was killed 23hrs after reperfusion and infarction area of brain was confirmed by 1.5% TTC (2,3,5-tryphenyl tetrazolium chloride) staining. Results: According to end size and insert length of Nylon thread, Middle cerebral artery occlusion (n=50), internal carotid artery occlusion (n= 14), distal middle cerebral artery occlusion (n= 36), anterior cerebral artery (n= 1) were induced. And no infarction (n= 50) was observed. Conclusion: According to weight of mice, the operator induced reversible cerebral artery occlusion model by different insert length (30.0~36.9g : 9.0mm, 37.0~40.0g : 9.5mm) of Nylon thread. Success of cerebral artery occlusion model was confirmed by checking infarction area using TTC staining. The success rate (66.9%, 101/151) of reversible cerebral artery occlusion model in the mouse and the operational conditions are shown.

A research on the emotion classification and precision improvement of EEG(Electroencephalogram) data using machine learning algorithm (기계학습 알고리즘에 기반한 뇌파 데이터의 감정분류 및 정확도 향상에 관한 연구)

  • Lee, Hyunju;Shin, Dongil;Shin, Dongkyoo
    • Journal of Internet Computing and Services
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    • v.20 no.5
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    • pp.27-36
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    • 2019
  • In this study, experiments on the improvement of the emotion classification, analysis and accuracy of EEG data were proceeded, which applied DEAP (a Database for Emotion Analysis using Physiological signals) dataset. In the experiment, total 32 of EEG channel data measured from 32 of subjects were applied. In pre-processing step, 256Hz sampling tasks of the EEG data were conducted, each wave range of the frequency (Hz); Theta, Slow-alpha, Alpha, Beta and Gamma were then extracted by using Finite Impulse Response Filter. After the extracted data were classified through Time-frequency transform, the data were purified through Independent Component Analysis to delete artifacts. The purified data were converted into CSV file format in order to conduct experiments of Machine learning algorithm and Arousal-Valence plane was used in the criteria of the emotion classification. The emotions were categorized into three-sections; 'Positive', 'Negative' and 'Neutral' meaning the tranquil (neutral) emotional condition. Data of 'Neutral' condition were classified by using Cz(Central zero) channel configured as Reference channel. To enhance the accuracy ratio, the experiment was performed by applying the attributes selected by ASC(Attribute Selected Classifier). In "Arousal" sector, the accuracy of this study's experiments was higher at "32.48%" than Koelstra's results. And the result of ASC showed higher accuracy at "8.13%" compare to the Liu's results in "Valence". In the experiment of Random Forest Classifier adapting ASC to improve accuracy, the higher accuracy rate at "2.68%" was confirmed than Total mean as the criterion compare to the existing researches.

Changes in Total Cerebral Blood Flow with Aging, Parenchymal Volume Changes, and Vascular Abnormalities: a Two-dimensional Phase-Contrast MRI Study (나이와 뇌실질부피 변화 및 혈관이상에 따른 총뇌혈류량 변화: 이차원 위상대조 자기공명영상을 이용한 연구)

  • Liu Haiying;Shin Tae-Beom;Youn Seong-Kuk;Oh Jong-Yong;Lee Young-Il;Choi Sun-Seob
    • Investigative Magnetic Resonance Imaging
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    • v.8 no.1
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    • pp.17-23
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    • 2004
  • Purpose : To evaluate changes in total cerebral blood flow (tCBF) with aging, parenchymal volume changes and vascular abnormalities, using 2 dimensional (D) phase-contrast magnetic resonance imaging (PC MRI). Materials and Methods : Routine brain MRI including T2 weighted image, time-of-flight (TOF) MR Angiography (MRA) and 2D PC MRI were performed in 73 individuals, including 12 volunteers. Normal subjects (12 volunteers, and 21 individuals with normal MRI and normal MRA) were classified into groups according to age (18-29, 30-49 and 50-66 years). For the group with abnormalities in brain MRIs, cerebral parenchymal volume changes were scored according to the T2 weighted images, and atherosclerotic changes were scored according to the MRA findings. Abnormal groups were classified into 4 groups: (i) mild reduction in volume, (ii) marked reduction in volume by parenchymal volume and atherosclerotic changes, and (iii) increased volume and (iv) Moya-moya disease. Volumetric flow was measured at the internal carotid artery (ICA) and vertebral artery bilaterally using the velocity-flow diagrams from PC MRI, and combined 4 vessel flows and tCBF were compared among all the groups. Results : The age-specific distribution of tCBFs in normal subjects were as follows: $12.0{\pm}2.1ml/sec$ in 18-29 years group, $11.8{\pm}1.9ml/sec$ in 30-49 years group, $10.9{\pm}2.2ml/sec$ in 50-66 years group. The distribution of tCBFs in the different subsets of the abnormal population were as follows: $9.5{\pm}2.5ml/sec$ in the group with mild reduction in volume, $7.6{\pm}2.0ml/sec$ in the group with marked reduction in volume, and $7.3{\pm}1.2ml/sec$ and $7.0{\pm}1.1ml/sec$ in the increased parenchymal volume and Moya-moya disease groups respectively. Conclusion : Total cerebral blood flow decreases with increasing age with a concomitant reduction in parenchymal volumes and increasing atherosclerotic changes. It is also reduced in the presence of increased parenchymal volume and Moya-moya disease.2D PC MRI can be used as a tool to evaluate tCBF with aging and in the presence of various conditions that can affect parenchymal volume and cerebral vasculature.

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Studies on the Distribution of Ants(Formicidea) in Korea(6) -The Vegetation, the Species Composition and the Colony Density ants in Mt. Namsan, Seoul- (한국산 개미의 분포에 관한 연구(6) -서울 남산의 식생과 개미군집의 종조성 및 Colony 밀도-)

  • 최병문;박경숙
    • Korean journal of applied entomology
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    • v.30 no.1
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    • pp.65-79
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    • 1991
  • In order to investigate the species composition and the colony density of ants in Mt. Namsan, Seoul, 39 quadrats were installed in 13 vegetations, 443 colonies of ants were collected from June, 1989 to October, 1990. As the result, 4 subfamilies, 23 genera, 28 species was confirmed. Among them, Cerapachys humicola $O_{GATA}$ is new to Korean fauna along with the subfamily Cerapachinae. For the species composition of ant communities in each vegetation, Robinia pseudoacacia vegetation(containing 3 subfamilies, 14 genera, 15 species-53.6% of all colonies collected in Mt. Namsan) and Quercus mongolica vegetation (3 subfamiles, 12 genera, 14 species -50%) showed relatively rich composition, while Platunus orientalis vegetation (3 subfamilies, 3 genera, 3 species) showed the simplest composition. Colony density was the highest in Prunus sargentii vegetation (7.875 colony /$m^2$) and the lowest in Platunus orientalis (1.000 colony/$m^2$). The relative density of Paratrechina flavipes proved to be the highest (RD = 0.422) and that of Cerapachys humicola $O_{GATA}$ Massor aciculatus was the lowest (RD = O. 002 respectively). In the analysis of the similarity of ant communities between each vegetation by S¢rensen's coefficient, Prunus sargentii was very similar to Sorbus alnifolia (0.745) and Pinus densiflora (0.736), but had the lowest similarity to Metasequoia glyptostoboides and Chamaecyparis pisifera vegetation (0.164 respectively). Dominance of ants in each vegetation analyzed by Simpson'formula was found to be high in Platunus orientalis ($\lambda$ = 0.393) and Sorbus alnifolia ($\lambda$ = 0.392) and the lowest in Metasequoia glyptostroboides vegetation($\lambda$= 0.067). The analysis of diversity by reverse Simpson's coefficient revealed that it was high in Metasequoia glyptostroboides ($d_s$ = 14.925), Pinus rigida ($d_s$ = 7.874) and was the lowest in Platunus orientalis vegetation ($d_s$ = 2.545). Evenness calculated by using d. and $d_{max}$(maximal diversity) was high in Metasequoia glyptostroboides ($E_s$ = 0.714) and Chamaecyparis pisifera vegetation ($E_s$ = 0.624). On the contrary, Quercus mongo/ica vegetation had the lowest value of evenness ($E_s$ = 0.182).

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2013 Records Regime Issues and Prospects for Public Records Management in Korea (한국 공공기록관리의 쟁점과 전망 2013년 기록관리체제를 위하여)

  • Ahn, Byung-Woo;Lee, Sang-min;Sim, Seong-Bo;Nam, Kyeong-Ho;Kim, Jin-Sung;O, Dong-Seok;Jeong, Tae-Young
    • The Korean Journal of Archival Studies
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    • no.34
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    • pp.3-28
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    • 2012
  • The year of 2013 is the first year that the new president takes the power and administrates the national affairs. In Korea, when the new president comes, the new administration brings big changes in the politics, economy, and society. The government management style has been changed according to the orientation and styles of the new president. Public records management is a critical and effective business tool to establish and carry out the government policies as well as an essential tool for democracy. Modern democracy is based on good governance. Creation and free use of full and accurate public records makes the good communication between the government and the public possible, and people's participation in the policy-making and surveillance of government activities for public good can work. During the present administration, communication between the president and the people was cutoff and people's participation in the national affairs have been further limited. Furthermore, in the present administration, the public records management was not regarded important, Whatever new administration comes, the year of 2013 is the time for the new administration to realize again the importance of the public records management and put it back to the normal track. Here are the major issues in the public records management to be concerned and resolved; (1) to ensure technological and institutional management of the electronic records in the government and safe transfer of the massive electronic records, (2) to establish an independent national records management and archives authority to be based on good governance, (3) to innovate the public records management in the public agencies including their agency records offices (RMO) and records management systems (RMS) (4) to establish local government archives and document local government policies and activities (5) supporting and promotion for documentation of the total society as a public service (6) expanding employment of professional records managers and archivists in the central and local governments, and standardization of professional competency and certification. In this paper, I will introduce the major issues in the public records management and suggest the policies and solutions that the Korean records professionals considered and discussed. This analysis and suggestions are the outcome of our professional considerations and discussions.