• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 2003년도 제8차 학술대회 초록집
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• pp.98-98
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• 2003

We will present various MR findings of hyperacute ischemic stroke with our own experiences in the management of the patients according to the findings. 대상 및 방법： A total of 441 patients were underwent 'acute stroke MR' imaging protocol between Mar. 2001 and Jun. 2003. The protocol included initial T2-weighted image (WI), diffusion WI (DWI, b=2000), time-of-flight (TOF) MR angiography (MRA), and pefusion WI(PWI), and follow-up T2WI, DWI, TOF MRA, and neck vessel contrast-enhanced MRA obtained three to five days after the insult. Among them, we retrospectively reviewed the MR findings and clinical courses of 193 patients with anterior circulation territorial infarction. Those ICA and MCA lesions were divided into six and five groups respectively according to the level and mechanism of the occlusion. PWI findings can be another factor in the management planning.

• Journal of Radiation Protection and Research
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• 제33권4호
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• pp.127-134
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• 2008

울진원전 3,4 호기의 가상적 중대사고로 인한 종합적인 경제적 리스크를 평가하였다. 이 연구의 목적을 위해 방사능 구름이 내륙을 향하는 것으로 가정하였다. 평가과정에서 불확실한 인자의 정량화에는 전문가 판단 및 의견도출에 유용한 것으로 알려진 델파이 기법을 이용하였다. 종합적인 경제적 리스크는 직접영향 비용과 간접영향 비용으로 구분되므로, 먼저 직접영향에 대한 비용을 평가하고, 예측된 가중치들 이용하여 직접영향 대비 간접영향 비용을 평가하였다. 행동학적 접근방법인 델파이 문제점을 보완하기 위해 수학적 접근방법인 베이지안 기법을 자료처리 과정으로 하는 모형을 적용하여 간접영향에 대한 경제적 충격량을 예측하였다. 1D 몬테칼로분석(MCA)으로 평가한 간접피해에 대한 가중치는 평균 2.59, 중앙값 2.08로 OECD/NEA에서 제시하는 가중치 1.25보다 높게 나타났다. 작은 국토나 방사선에 민감한 대중 성향과 같은 인지들이 패널의 판단에 영향을 미쳤을 수 있다. 직접피해 평가모델의 모수를 U형과 V형으로 구분하고 2D MCA를 사용한 종합적 경제적 리스크는 중앙값의 50%ile을 기준으로 2006년 국내총생산의 3.9%에 해당되었으며, 직접피해 영향이 가장 큰 자산 및 전력손실 비용을 제외하면 총 경제적 리스크는 국내총생산의 2.2% 수준이었다. 이 결과는 원전 비상계획과 대응태세 준비에 대한 투자 정당화에 참조 자료로 이용될 수 있다.

• 대한본초학회지
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• 제25권2호
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• pp.71-79
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• 2010

Objectives : In this study, the neuroprotective effects of modified Boyanghwano-Tang (mBHT) and the major medicinal plants, Astragali Radix(AR) and Salviae Miltiorrhizae Radix(SMR) were investigated in transient middle cerebral artery occlusion (tMCAO)-induced ischemic stroke of rats. Methods : mBHT(400 mg/kg) and AR(154 mg/kg) or SMR(62 mg/kg) water extract orally injected in rats after 90 min occlusion of MCA and then allow reperfusion to 24 h. Brain infarction was measured by TTC staining and the expressions of NOS isoforms and apoptotic molecules were determined in ischemic brain by Western blot. Results : The results showed that mBHT has stronger neuropreotective property through inhibitions of the PARP cleaved and caspase-3 activation in ischemic rats, and could reduced infarction volumes comparison of those of AR or SMR, respectively. While, AR extract has an angiogenic property through increasing the expressions of eNOS and VEGF, and SMR extract has a strong anti-inflammatory effects through inhibition of iNOS expression in ischemic brains. Conclusions : These results suggest that mBHT has multifactorial therapeutic advantages through anti-apoptosis, anti-inflammation and angiogenesis for ischemic stroke based on a synergistic combination of ingradients rather than monotherapy.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.1270-1273
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• 2004

The combination of methane-chemical activation and Self-propagating High-temperature synthesis (SHS) has widened the possibilities for both methods. For YBCO systems the investigation showed that a short-term mechano-chemical activation of initial powders before SHS leads to single-phase and ultra-fine products. A new technique for preparation ultra-fine high-temperature superconductors of YBCO composition with a grain size d < $1{\mu}m$ is developed. The specific feature of the technique is formation of the $YBa_2Cu_3O_{7-x}$ crystalline lattice directly from an X-ray amorphous state arising as a result of mechanical activation of the original oxide mixture. The technique allows the stage of formation of any intermediate reaction products to be ruled out. X-ray and magnetic studies of ultra-fine high temperature superconductors (HTS) are carried out. Dimension effects associated with the microstructure peculiarities are revealed. A considerable enhancement of inter-grain critical currents is found to take place in the ultra-fine samples investigated.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(1)
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• pp.163-168
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• 1996

Simulations of Wolsong-1 Phase-B commissioning measurements have been performed, as part of the program to validate WIMS-AECL lattice cell calculations for application to CANDU reactor simulations in RFSP. A required component of these simulations is the calculation of incremental cross sections representing reactivity control devices in the reactor. The incremental cross section properties of the Wolsong-1 adjusters, Mechanical Control Absorbers (MCA) and liquid Zone Control Units (ZCU) are based on the WIMS-AECL/MULTICELL modelling methods and the results are compared with those of WIMS-AECL/DRAGON-2 modelling methods.

• 전기전자학회논문지
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• 제22권3호
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• pp.638-644
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• 2018

본 논문에서는 플라스틱 Scintillator와 NaI(TI) 검출기를 이용하여 움직이는 차량 적재물에 존재하는 다수의 방사선원 위치를 3차원으로 판별하는 측정시스템을 제안한다. 제안하는 시스템은 방사선량 측정용 플라스틱 Scintillator, 2채널 펄스 카운터, 핵종 분석용 NaI(TI) 검출기 및 1채널 MCA Board 등으로 구성된다. 방사선원 위치판별 알고리즘은 방사선량의 거리의 자승에 반비례한 특성($1/r^2$)과 장치와의 각도(${\theta}$)에 따른 보상을 통해 계산된 방사선원의 CPS 값의 비율을 SVM 분류를 통하여 방사선원의 위치(X, Y)를 구할 수 있다. (Z) 좌표 값은 단위 시간당 움직이는 대상체의 속도에 따라 정해지게 되며 이는 단위주기당 백그라운드 스펙트럼을 제외한 순수 핵종의 스펙트럼을 분석한 후 핵종 유무 판별을 진행한 뒤 해당 핵종의 위치를 판별하게 된다. 본 논문에서 제안한 시스템의 위치 판별 실험 결과 ${\pm}1m$ 이내의 국제표준오차를 나타내었다. 따라서 본 논문에서 제안한 시스템의 유효성이 입증되었다.

• Journal of Korean Neurosurgical Society
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• 제61권5호
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• pp.548-558
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• 2018

Objective : Diagnosing acute cerebral infarction is crucial in determining prognosis of stroke patients. Although many serologic tests for prompt diagnosis are available, the clinical application of serologic tests is currently limited. We investigated whether $S100{\beta}$, matrix metalloproteinase-9 (MMP-9), D-dimer, and heat shock protein 70 (HSP70) can be used as biomarkers for acute cerebral infarction. Methods : Focal cerebral ischemia was induced using the modified intraluminal filament technique. Mice were randomly assigned to 30-minute occlusion (n=10), 60-minute occlusion (n=10), or sham (n=5) groups. Four hours later, neurological deficits were evaluated and blood samples were obtained. Infarction volumes were calculated and plasma $S100{\beta}$, MMP-9, D-dimer, and HSP70 levels were measured using enzyme-linked immunosorbent assay. Results : The average infarction volume was $12.32{\pm}2.31mm^3$ and $46.9{\pm}7.43mm^3$ in the 30- and 60-minute groups, respectively. The mean neurological score in the two ischemic groups was $1.6{\pm}0.55$ and $3.2{\pm}0.70$, respectively. $S100{\beta}$, MMP-9, and HSP70 expressions significantly increased after 4 hours of ischemia (p=0.001). Furthermore, $S100{\beta}$ and MMP-9 expressions correlated with infarction volumes (p<0.001) and neurological deficits (p<0.001). There was no significant difference in D-dimer expression between groups (p=0.843). The area under the receiver operating characteristic curve (AUC) showed high sensitivity and specificity for MMP-9, HSP70 (AUC=1), and $S100{\beta}$ (AUC=0.98). Conclusion : $S100{\beta}$, MMP-9, and HSP70 can complement current diagnostic tools to assess cerebral infarction, suggesting their use as potential biomarkers for acute cerebral infarction.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1439-1441
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• 2003

The World Health Organisation has identified ‘Fluorosis’as a serious bone disease caused by groundwater. Though the fluoride content in groundwater is a natural phenomenon, when the permissible limit of fluoride is exceeded the consequences may be fatal. This study is identified areas of high fluoride content in the Dharmapuri district of India, which is one of the major districts severely affected by fluorosis (WHO). The approach to this problem is by using GIS as a tool to locate areas of high risk. Ground Water samples collected from 35 randomly located wells (open / bore wells) in the district were analysed for fluoride content. The results were compared with the standards of WHO (World Health Organisation ), ICMR (Indian Council of Medical Research ), BIS (Bureau of Indian Standard) and PHE (Public Health Engineering) and interpolated using IDW and spline methods using Arcview GIS 3.2 a. A computer based automated information system was developed in Arcview Avenue 3.2a, so as to enable the user to visit the risk areas at his desktop and to remediate measures as and when required.

• The Korean Journal of Pain
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• 제21권2호
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• pp.119-125
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• 2008

Background: Cerebral blood vessels are innervated by sympathetic nerves from the superior cervical ganglia (SCG), and these nerves may influence the cerebral blood flow. The purpose of the present study was to evaluate the neuroprotective effect of superior cervical sympathetic ganglion block in rats that were subjected to focal cerebral ischemia/reperfusion injury. Methods: Eighty male Sprague-Dawley rats (270-320 g) were randomly assigned to one of two groups (the ropivacaine group and a control group). In all the animals, brain injury was induced by middle cerebral artery (MCA) reperfusion that followed MCA occlusion for 2 hours. The animals of the ropivacaine group received $30{\mu}l$ of 0.75% ropivacaine, and their SCG. Neurologic score was assessed at 1, 3, 7 and 14 days after brain injury. Brain tissue samples were then collected. The infarct ratio was measured by 2.3.5-triphenyltetrazolium chloride staining. The terminal deoxynucleotidyl transferase mediated dUTP-biotin nick-end labeled (TUNEL) reactive cells and the cells showing caspase-3 activity were counted as markers of apoptosis at the caudoputamen and frontoparietal cortex. Results: The death rate, the neurologic score and the infarction ratio were significantly less in the ropivacaine group 24 hr after ischemia/reperfusion injury. The number of TUNEL positive cells in the ropivacaine group was significantly lower than those values of the control group in the frontoparietal cortex at 3 days after injury, but the caspase-3 activity was higher in the ropivacaine group than that in the control group at 1 day after injury. Conclusions: The study data indicated that a superior cervical sympathetic ganglion block may reduce the neuronal injury caused by focal cerebral ischemia/reperfusion, but it may not prevent the delayed damage.

• The Plant Pathology Journal
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• 제29권1호
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• pp.31-41
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• 2013

The presence of Citrus tristeza virus (CTV) has previously been reported in citrus growing regions of Turkey. All serologically and biologically characterized isolates including I$\breve{g}$d${\i}$r, which was the first identified CTV isolates from Turkey, were considered mild isolates. In this study, molecular characteristics of the I d r isolate were determined by different methods. Analysis of the I$\breve{g}$d${\i}$r isolate by western blot and BD-RT-PCR assays showed the presence of MCA13 epitope, predominantly found in severe isolates, in the I$\breve{g}$d${\i}$r isolate revealing that it contains a severe component. For further characterization, the coat protein (CP) and the RNA-depen-dent RNA polymerase (RdRp) genes representing the 3' and 5' half of CTV genome, respectively, were amplified from dsRNA by RT-PCR. Both genes were cloned separately and two clones for each gene were sequenced. Comparisons of nucleotide and deduced amino acid sequences showed that while two CP gene sequences were identical, two RdRp clones showed only 90% and 91% sequence identity in their nucleotide and amino acid sequences, respectively, suggesting a mixed infection with different strains. Phylogenetic analyses of the CP and RdRp genes of I$\breve{g}$d${\i}$r isolate with previously characterized CTV isolates from different citrus growing regions showed that the CP gene was clustered with NZRB-TH30, a resistance breaking isolate from New Zealand, clearly showing the presence of severe component. Furthermore, two different clones of the RdRp gene were clustered separately with different CTV isolates with a diverse biological activity. While the RdRp-1 was clustered with T30 and T385, two well-characterized mild isolates from Florida and Spain, respectively, the RdRp-2 was most closely related to NZRB-G90 and NZRB-TH30, two well-characterized resistance breaking and stem pitting (SP) isolates from New Zealand confirming the mixed infection. These results clearly demonstrated that the I$\breve{g}$d${\i}$r isolate, which was previously described as biologically a mild isolate, actually contains a mixture of mild and severe strains.