• 한국물환경학회지
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• 제32권3호
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• pp.243-252
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• 2016

In cases of water pollution accidents, accurate prediction for arrival time and concentration of contaminants in a river is essential to take proper measures and minimize their impact on downstream water intake facilities. It is critical to fully understand the behavior characteristics of contaminants on river surface, especially in case of oil spill accidents. Therefore, in this study, the effects of main parameters of advection and diffusion of contaminants were analyzed and validated by comparing the results of Lagrangian particle tracking (LPT) simulation of Environmental Fluid Dynamic Code (EFDC) model with those of Global Position System (GPS)-equipped drifter experiment. Prevention scenario modeling was accomplished by taking cases of movable weir operation into account. The simulated water level and flow velocity fluctuations agreed well with observations. There was no significant difference in the speed of surface particle movement between 5 and 10 layer modeling. Therefore, 5 layer modeling could be chosen to reduce computational time. It was found that full three dimensional modeling simulated wind effects on surface particle movements more sensitively than depth-averaged two dimensional modeling. The diffusion range of particles was linearly proportional to horizontal diffusivity by sensitivity analysis. Horizontal diffusivity estimated from the results of GPS-equipped drifter experiment was 0.096 m²/sec, which was considered to be valid for applying the LPT module in this area. Finally, the scenario analysis results showed that particle movements could be stagnant when discharge from the upstream weir was reduced, implying the possibility of securing time for mitigation actions such as oil boom installation and wiping oil contaminants. The outcomes of this study can help improve the prediction accuracy of particle tracking simulation to establish the most suitable mitigation plan considering the combination of movable weir operation.

• Journal of Korean Neurosurgical Society
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• 제67권4호
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• pp.442-450
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• 2024

Objective : Cerebral hyperperfusion syndrome (CHS) manifests as a collection of symptoms brought on by heightened focal cerebral blood flow (CBF), afflicting nearly 30% of patients who have undergone superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis. The aim of this study was to investigate whether the amalgamation of magnetic resonance imaging (MRI) fluid-attenuated inversion recovery (FLAIR) and apparent diffusion coefficient (ADC) imaging via MRI can discern cerebral hyperemia after STA-MCA anastomosis surgery. Methods : A retrospective study was performed of patients who underwent STA-MCA anastomosis due to Moyamoya disease or atherosclerotic steno-occlusive disease. A protocol aimed at preventing CHS was instituted, leveraging the use of MRI FLAIR. Patients underwent MRI diffusion with FLAIR imaging 24 hours after STA-MCA anastomosis. A high signal on FLAIR images signified the presence of hyperemia at the bypass site, triggering a protocol of hyperemia care. All patients underwent hemodynamic evaluations, including perfusion MRI, single-photon emission computed tomography (SPECT), and digital subtraction angiography, both before and after the surgery. If a high signal intensity is observed on MRI FLAIR within 24 hours of the surgery, a repeat MRI is performed to confirm the presence of hyperemia. Patients with confirmed hyperemia are managed according to a protocol aimed at preventing further progression. Results : Out of a total of 162 patients, 24 individuals (comprising 16 women and 8 men) exhibited hyperemia on their MRI FLAIR scans following the procedure. SPECT was conducted on 23 patients, and 11 of them yielded positive results. All 24 patients underwent perfusion MRI, but nine of them showed no significant findings. Among the patients, 10 displayed elevations in both CBF and cerebral blood volume (CBV), three only showed elevation in CBF, and two only showed elevation in CBV. Follow-up MRI FLAIR scans conducted 6 months later on these patients revealed complete normalization of the previously observed high signal intensity, with no evidence of ischemic injury. Conclusion : The study determined that the use of MRI FLAIR and ADC mapping is a competent means of early detection of hyperemia after STA-MCA anastomosis surgery. The protocol established can be adopted by other neurosurgical institutions to enhance patient outcomes and mitigate the hazard of permanent cerebral injury caused by cerebral hyperemia.

• Clinical and Experimental Pediatrics
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• 제61권8호
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• pp.245-252
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• 2018

Purpose: This study investigated patterns of ischemic injury observed in brain images from patients with neonatal group B Streptococcal (GBS) meningitis. Methods: Clinical findings and brain images from eight term or near-term newborn infants with GBS meningitis were reviewed. Results: GBS meningitis was confirmed in all 8 infants via cerebrospinal fluid (CSF) analysis, and patients tested positive for GBS in both blood and CSF cultures. Six infants (75.0%) showed early onset manifestation of the disease (<7 days); the remaining 2 (25.0%) showed late onset manifestation. In 6 infants (75%), cranial ultrasonography showed focal or diffuse echogenicity, suggesting hypoxic-ischemic injury in the basal ganglia, cerebral hemispheres, and periventricular or subcortical white matter; these findings are compatible with meningitis. Findings from magnetic resonance imaging (MRI) were compatible with bacterial meningitis, showing prominent leptomeningeal enhancement, a widening echogenic interhemisphere, and ventricular wall thickening in all infants. Restrictive ischemic lesions observed through diffusion-weighted imaging were evident in all eight infants. Patterns of ischemic injury as detected through MRI were subdivided into 3 groups: 3 infants (37.5%) predominantly showed multiple punctuate lesions in the basal ganglia, 2 infants (25.0%) showed focal or diffuse cerebral infarcts, and 3 infants (37.5%) predominantly showed focal subcortical or periventricular white matter lesions. Four infants (50%) showed significant developmental delay or cerebral palsy. Conclusion: Certain patterns of ischemic injury are commonly recognized in brain images from patients with neonatal GBS meningitis, and this ischemic complication may modify disease processes and contribute to poor neurologic outcomes.

• 한국통신학회논문지
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• 제19권3호
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• pp.451-461
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• 1994

이 논문에서는 기본통신 환경은 발전하였으나 데이터통신 환경이 저개발된 데이터통신 후발국을 위하여 빠른 시간내에 데이터통신 서비스 수요를 만족시키며, 고속화 및 서비스 다양화를 요구하는 통신기술발전 방향에 부합하고, 데이터통신망 확산 및 비용에 유리한 공중패킷교환망의 구축 전략에 대하여 다루었다. 데이터통신 후발국의 통신망 특성 및 데이터통신 수요의 특징을 분석한 후 정보통신망 구축 전략으로서 종합정보통신망에 의한 공중패킷교환망 구성이 적합함을 보였다. 90년대 이후 데이터통신 후발국의 통신망 진화를 고려하며, 투자 대비 효과를 극대화할 수 있는 종합 정보통신망에 의한 패킷교환망 구성 방안으로 패킷교환기능을 종합정보통신망 교환기내에 실현하는 적극적인 방식과 망 구조의 진화 예측에 따른 삼단계 망연동 방식을 제안하였다. 제안된 패킷교환 망 구성 개념이 데이터통신 후발국 시장을 목표로 하는TDX-10 ISDN 교환시스템에서 구현 가능함을 보였다.

• Clinical and Experimental Pediatrics
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• 제57권6호
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• pp.264-270
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• 2014

Purpose: Acute necrotizing encephalopathy (ANE) is a fulminant disease of the brain characterized by bilateral thalamic lesions, and is prevalent among children in East Asia. The prognosis of ANE is usually poor with a high mortality rate and neurological sequelae. This study aimed to delineate the clinical characteristics and prognostic factors of ANE. Methods: We retrospectively analyzed clinical data of 399 pediatric patients with encephalitis who were admitted to Samsung Medical Center from December 1998 to March 2011. We enrolled ten patients (11 cases) with ANE and analyzed their demographic, clinical, and neuroimaging data. The location and extent of the brain regions were checked based on fluid-attenuated inversion recovery, T1-, and T2-weighted imaging findings; the presence of contrast enhancement, restricted diffusion, and hemorrhage. Results: Ten patients were identified, including one patient with two episodes. The median age of onset was 1.5 years (0.4-8.4 years). The mortality rate was 40%, and only 30% of patients survived without neurological sequelae. The definite involvement of the brainstem on brain magnetic resonance imaging was significantly correlated with mortality (P =0.04). Conclusion: Broad and extensive brainstem involvement suggested the fulminant course of ANE. Early diagnosis of ANE before brainstem involvement, through careful identification of symptoms of brain dysfunction, may be the best way to achieve better neurological outcomes.

• STI Policy Review
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• 제1권1호
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• pp.1-21
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• 2010

To achieve the "low carbon green growth" vision, the first step is securing core technologies. Therefore, S&T policy direction for green technology development is urgently needed. As of 2008, investment in green technology (GT) development hovered around 10% of the government's total R&D budget. Thus, the Korean government developed a plan to increase that percentage to 15%, by 2013. To develop reasonable investment strategies for green technology development, targeted strategies that reflect technology and market changes by green technology area are needed. However, the overall planning and coordination of national GT development is currently split among, approximately, 10 government ministries. To establish an efficient green technology development system, the so-called "Green Technology R&D Council" should be launched in collaboration with the Presidential Committee on Green Growth and the National Science and Technology Council. Furthermore, to build a solid foundation for commercializing the outcomes of GT development projects and promote GT transfer, the government should undertake two initiatives. First, the government should reinforce GT R&D performance management, by establishing a GT R&D performance management and evaluation system. Second, the government should implement the "customized packaged support for promoting green technology business rights and commercialization" and present "e-marketplace for market-oriented green technologies". Creating a pan-ministerial policy for GT development policy would necessitate restructuring the HR(Human Resources) development system, which is currently separated by technology area. Based upon mid/long-term HR supply and demand forecasts, the government should design differentiated HR development projects, continuously evaluate those projects, and reflect the evaluation results in future policy development. Finally, to create new GT-related industries, the "Green TCS (Testing, Certification, and Standards) System" needs to be implemented. For objective evaluation and diffusion of R&D results by green technology area, a common standardization plan for testing, analysis, and measurement, like the "Green TCS", should be developed and integrated.

• 기술혁신학회지
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• 제20권4호
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• pp.989-1014
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• 2017

연구의 책임성을 추구하는 주요 선진국은 과학 연구와 기술 개발에 있어 성별특성분석의 중요성을 인식하여 젠더혁신을 진행하고 있다. 우리나라는 Fast Follower 단계에서 First Mover로 나아가기 위한 전략의 하나로 미개척 연구 분야를 선점하기 위한 젠더혁신을 적극 추진할 필요가 있다. 과학기술분야에서 젠더혁신을 확산하려면 우선 연구개발 사업 전 과정에서 성/젠더분석을 반영한 정책을 천명하고, 연구개발 지원 사업의 제안부터 평가에 이르기까지 젠더혁신 연구지원 방안을 도입하여야 한다. 특히 우리나라의 연구개발 추진체계에서 새로운 젠더혁신 연구를 정책적으로 지원하려면 법적 기반이 선행되어야 실효성을 거둘 수 있을 것이다. 본 연구에서는 해외사례를 분석하여 젠더혁신 관련 법 개정안을 제언하였다.

• Journal of Neurogastroenterology and Motility
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• 제24권4호
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• pp.512-527
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• 2018

This review provides a comprehensive overview of brain imaging studies of the brain-gut interaction in functional gastrointestinal disorders (FGIDs). Functional neuroimaging studies during gut stimulation have shown enhanced brain responses in regions related to sensory processing of the homeostatic condition of the gut (homeostatic afferent) and responses to salience stimuli (salience network), as well as increased and decreased brain activity in the emotional response areas and reduced activation in areas associated with the top-down modulation of visceral afferent signals. Altered central regulation of the endocrine and autonomic nervous responses, the key mediators of the brain-gut axis, has been demonstrated. Studies using resting-state functional magnetic resonance imaging reported abnormal local and global connectivity in the areas related to pain processing and the default mode network (a physiological baseline of brain activity at rest associated with self-awareness and memory) in FGIDs. Structural imaging with brain morphometry and diffusion imaging demonstrated altered gray- and white-matter structures in areas that also showed changes in functional imaging studies, although this requires replication. Molecular imaging by magnetic resonance spectroscopy and positron emission tomography in FGIDs remains relatively sparse. Progress using analytical methods such as machine learning algorithms may shift neuroimaging studies from brain mapping to predicting clinical outcomes. Because several factors contribute to the pathophysiology of FGIDs and because its population is quite heterogeneous, a new model is needed in future studies to assess the importance of the factors and brain functions that are responsible for an optimal homeostatic state.

• 농업과학연구
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• 제48권3호
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• pp.557-565
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• 2021

Interest in research on various medicinal plants has increased globally over the last few decades, possibly due to their possible antibacterial and antioxidant activities. The present study was conducted to verify the antioxidant effects, antibacterial activity, and collagen synthesis and cell viability outcomes of adipocytes upon exposure to Abeliophyllum distichum Nakai (AdN). Antibacterial activity was measured through the Disc diffusion method to compare the growth ability of pathogenic microorganisms (E.coli, Salmonella). The absorbance was measured at 560 nm to calculate the active oxygen scavenging ability. Fibroblasts were dispensed in a 96-well plate at a density of 1 × 10⁵ cells·well^-1. The amount of procollagen was measured in each case using a procollagen type 1 C-peptide EIA KIT. The cytotoxicity of the Abeliophyllum distichum Nakai extract against animal adipocytes (Hanwoo backfat cells) was determined using a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay, a method that measures the conversion of MTS to Formazan by means of mitochondrial dehydrogenases. The concentrations of the samples were made to be 0.0125, 0025, 0.05, 0.1, and 0.5% and all were -completely absorbed into the disc in an incubator at 37℃ for 24 to 36 hours. For the 0.125 mg·disc^-1, effects of Abeliophyllum distichum Nakai on the antioxidant effect, antibacterial activity, and cell viability of adipocytes were found. However, Abeliophyllum distichum Nakai had no effect on collagen synthesis, thus suggesting that AdN extracts may be useful for the prevention and/or treatment of obesity.

• Journal of Trauma and Injury
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• 제35권3호
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• pp.209-214
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• 2022

We describe a case of hyperbaric oxygen therapy (HBOt) as an adjunct to treatment of a crush injury to the hand. A 34-year-old male paramedic was involved in a motor vehicle accident and admitted for diagnosis and surgical treatment. He sustained a crush injury to his right hand and presented with significant muscle damage, including multiple fractures and dislocations, an avulsion injury of the flexor tendons, and amputation of the distal phalanx of the little finger. He underwent reconstructive surgery and received HBOt over the following days. In the following 2 months, he lost the distal and middle phalanges of the little finger and recovered hand function. Posttraumatic compartment syndrome responds well to HBOt, which reduces edema and contributes to angiogenesis, as well as promoting the cascade of healing events. High-energy trauma causes massive cell destruction, and the blood supply is usually not sufficient to meet the oxygen demands of viable tissues. Hyperbaric oxygenation by diffusion through interstitial and cellular fluids increases tissue oxygenation to levels sufficient for the host's responses to injury to work and helps control the delayed inflammatory reaction. HBOt used as an adjunct to surgical treatment resulted in early healing and rehabilitation, accelerating functional recovery. The results suggest that adjunctive HBOt can be beneficial for the treatment of crush injuries of the hand, resulting in better functional outcomes and helping to avoid unnecessary amputations.