• 한국물환경학회지
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• 제31권4호
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• pp.367-376
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• 2015

The momentum and kinetic turbulent energy carried by the wind to a stratified lake lead to basin-scale motions, which provide a major driving force for vertical and horizontal mixing. A three-dimensional (3D) hydrodynamic model was applied to Lake Tahoe, located between California and Nevada, USA, to simulate the dominant basin-scale internal waves in the deep lake. The results demonstrated that the model well represents the temporal and vertical variations of water temperature that allows the internal waves to be energized correctly at the basin scale. Both the model and thermistor chain (TC) data identified the presence of Kelvin modes and Poincare mode internal waves. The lake was weakly stratified during the study period, and produced large amplitude (up to 60 m) of internal oscillations after several wind events and partial upwelling near the southwestern lake. The partial upwelling and followed coastal jets could be an important feature of basin-scale internal waves because they can cause re-suspension and horizontal transport of fine particles from nearshore to offshore. The internal wave dynamics can be also associated with the distributions of water quality variables such as dissolved oxygen and nutrients in the lake. Thus, the basin-scale internal waves and horizontal circulation processes need to be accurately modeled for the correct simulation of the dissolved and particulate contaminants, and biogeochemical processes in the lake.

• BMB Reports
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• 제40권1호
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• pp.82-87
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• 2007

Our heterologous expression system of the human ferritin H-chain gene (hfH) allowed us to characterize the cellular effects of ferritin in yeasts. The recombinant Saccharomyces cerevisiae (YGH2) evidenced impaired growth as compared to the control, which was correlated with ferritin expression and with the formation of core minerals. Growth was recovered via the administration of iron supplements. The modification of cellular iron metabolism, which involved the increased expression of high-affinity iron transport genes (FET3 and FTR1), was detected via Northern blot analysis. The findings may provide some evidence of cytosolic iron deficiency, as the genes were expressed transcriptionally under iron-deficient conditions. According to our results examining reactive oxygen species (ROS) generation via the fluorescence method, the ROS levels in YGH2 were decreased compared to the control. It suggests that the expression of active H-ferritins reduced the content of free iron in yeast. Therefore, present results may provide new insights into the regulatory network and pathways inherent to iron depletion conditions.

• Macromolecular Research
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• 제15권5호
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• pp.459-464
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• 2007

Polymer electrolyte membranes, featuring ionic channels, were prepared from sulfonated dextran/ poly(vinyl alcohol) (sD/PVA) membranes. A stiff sulfated dextran was chosen as the route for ionic transport, since ionic sites are located along the stiff dextran main chain. The sD/PVA blend membranes were annealed and then chemically crosslinked. The characteristics of the crosslinked sD/PVA membranes were investigated to determine their suitability as proton exchange membranes. The proton conductivity was found to increase with increasing amounts of sD inside the membrane, which reached a maximum and then decreased when the sD content exceeded 30 wt%, while the methanol permeability increased with increasing sD content. The good dispersion of sD inside the membrane, which serves as an ionic channels mimic, played a significant role in proton transportation.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.317-317
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• 2010

This paper reports syntheses of $TiO_2$ nanocubes and theirs application to DSSC. We synthesized $TiO_2$ nanocubes via solvothermal method using titanium isopropoxide (TTIP) and tetramethylammoiumhydroxide (TMAH). By adding longer alkyl chain ammonium hydroxide that slowed down the growth rate of the crystal, $TiO_2$ nanocubes were obtained with average particle size in the range of 40 nm to 70 nm. By TEM investigation, each particle was found to be single crystal of anatase having six-faces of (001) and {100} crystallographic planes truncated by {101} series of planes, which are clearly distinguishable from spherical nanoparticles. Among various application, utilizing nanocubes as photo-electrode in dye-sensitized solar cell, we investigated photo-electron conversion performances in comparison with spherical shaped $TiO_2$ nanoparticles by I-V characteristics and IPCE measurements, etc.. Photocurrent-transient analysis revealed that $TiO_2$ nanocubes have a higher transient electron transfer rate by more than 10 times compared with spherical particles of similar size. Fast electron transport along the cube edges having small curvature was suggested as a plausible origin of high diffusion coefficient of electron in nanocube $TiO_2$.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제20권4호
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• pp.259-262
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• 2017

Mitochondria play essential role in eukaryotic cells including in the oxidative phosphorylation and generation of adenosine triphosphate via the electron-transport chain. Therefore, defects in mitochondrial DNA (mtDNA) can result in mitochondrial dysfunction which leads to various mitochondrial disorders that may present with various neurologic and non-neurologic manifestations. Mutations in the nuclear gene polymerase gamma (POLG) are associated with mtDNA depletions, and Alpers-Huttenlocher syndrome is one of the most severe manifestations of POLG mutation characterized by the clinical triad of intractable seizures, psychomotor regression, and liver failure. The hepatic manifestation usually occurs late in the disease's course, but in some references, hepatitis was reportedly the first manifestation. Liver transplantation was considered contraindicated in Alpers-Huttenlocher syndrome due to its poor prognosis. We acknowledged a patient with the first manifestation of the disease being hepatic failure who eventually underwent liver transplantation, and whose neurological outcome improved after cocktail therapy.

• 한국콘텐츠학회논문지
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• 제9권6호
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• pp.25-36
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• 2009

본 논문에서는 RFID 시스템에서 많이 발생하는 경로 질의와 포함 관계 질의를 효과적으로 처리하기 위한 데이터 관리 기법을 제안한다. 제안하는 데이터 관리 기법은 다양한 포함 관계에 대한 경로 정보를 유연하게 표현함으로써 운송 도중 발생하는 포함 관계의 변경 및 개별 단위의 물품 경로까지 지원한다. 또한, 공급망의 구조 정보를 활용한 경로 정보의 압축으로 저장되는 데이터의 양을 감소시킬 수 있다. 기존 기법들과 비교 평가를 수행한 결과 저장 공간과 질의 처리 측면에서 성능이 향상됨을 확인할 수 있었다.

• Journal of Radiation Protection and Research
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• 제8권2호
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• pp.41-46
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• 1983

방사성핵종의 대기방출로 인한 인근주민의 연간 집단선량을 대기확산모델과 USNRC에서 제안된 지상먹이연쇄모델을 결부시켜 AIRDOS-EPA전산코드를 사용하여 평가하였다. 평가결과는 전신의 경우, $3.348{\times}10^{-1}manrem$으로 GASPAR전산코드에 의해 계산된 값과 다소 차이가 있었으나 갑상선의 경우, 84.95manrem으로 아주 낮게 평가되었다.

• 환경생물
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• 제41권2호
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• pp.145-166
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• 2023

Parrots have been threatened by global trade to meet their high demand as pets. Controlling parrot trade is essential because parrots play a vital role in the ecosystem. Accurate species identification is crucial for controlling parrot trade. Parrots have been traded as eggs due to their advantages of lower mortality rates and more accessible transport than live parrots. A molecular method is required to identify parrot eggs because it is difficult to perform identification using morphological features. In this study, DNAs were obtained from 43 unidentified parrot eggs using a non-destructive sampling method. Partial cytochrome b (CYTB) gene was then successfully amplified using polymerase chain reaction (PCR) and sequenced. Sequences newly obtained in the present study were compared to those available in the GenBank by database searching. In addition, phylogenetic analysis was conducted to identify species using available sequences in GenBank along with sequences reported in previous studies. Finally, the 43 parrot eggs were successfully identified as seven species belonging to two families and seven genera. This non-destructive sampling method for obtaining DNA and molecular identification might help control the trade of parrot eggs and prevent their illegal trade.

• 한국전자통신학회논문지
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• 제17권2호
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• pp.207-212
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• 2022

철도 교통시스템은 최근 들어 각 구성 요소의 자동화 단계를 넘어 지능화를 추구하는 스마트 철도로 발전하고 있다. IoT(: Internet of Things), 빅데이터, 딥러닝, AI(: Artificial Intelligence), 블록체인 등 ICT(: Information & Communications Technology) 기술에 기반한 스마트 철도는 국내외 철도 기술에 많은 발전적 변화를 일으킬 것으로 예상된다. 본 논문에서는 이와 같은 스마트 철도 시스템(SRS: Smart Railway System)의 근간을 이루는 철도 통신 기술의 국내외 표준화 동향에 대해서 살펴보고 향후 우리나라 철도교통시스템에서의 열차제어 기술(CBTC)이 세계 철도산업에서의 선도 기술이 되기 위한 지향점(UBTC)에 관하여 논한다.

• International Journal of Stem Cells
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• 제17권2호
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• pp.113-119
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• 2024

This report presents guidelines for the systematic management of packaging, storage, transportation, and traceability of source cells used for organoid research. Given the important role of source cells in organoid studies, it is important to ensure the preservation of their quality and integrity throughout transportation and distribution processes. The proposed guidelines, therefore, call for a cohesive strategy through these stages to minimize the risks of contamination, deterioration, and loss-threats that significantly compromise the safety, efficacy, and efficiency of source cells. Central to these guidelines is the quality control measures that include roles and responsibilities across the entire supply chain, with recommendations specific to packaging materials, transportation facilities, and storage management. Furthermore, the need for an integrated management system is emphasized, spanning from source cell collection to the final application. This system is crucial for maintaining the traceability and accountability of source cells, facilitating the sharing, distribution, and utilization on a global scale, and supporting to advance organoid research and development.