• Environmental Engineering Research
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• 제23권4호
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• pp.345-353
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• 2018

This paper summarizes results of research on the electrochemical (EC) degradation of disinfection by-products (DBPs) and iodine-containing contrast media (ICMs), with the focus on EC reductive dehalogenation. The efficiency of EC dehalogenation of DBPs increases with the number of halogen atoms in an individual DBP species. EC reductive cleavage of bromine from parent DBPs is faster than that of chlorine. EC data and quantum chemical modeling indicate that the EC reduction of iodine-containing DBPs (I-DBPs) is characterized by the formation of active iodine that reacts with the organic substrate. The occurrence of ICMs has attracted attention due to their association with the generation of I-DBPs. Indirect EC oxidation of ICMs using anodes that produce reactive oxygen species can result in a complete degradation of these compounds yet I-DBPs are formed in the process. Reductive EC deiodination of ICMs is rapid and its overall rate is diffusion-controlled yet I-DBPs are also produced in this reaction. Further progress in practically feasible EC methods to remove DBPs, ICMs and other trace-level organic contaminants requires the development of novel electrocatalytic materials, elimination of mass transfer limitations via innovative design of 3D electrodes and EC reactors, and further progress in the understanding of intrinsic mechanisms of EC reactions of DBPs and TrOC at EC interfaces.

• Biomolecules & Therapeutics
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• 제31권6호
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• pp.648-654
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• 2023

Oxidative stress-induced melanocyte apoptosis is linked to the immune system and plays a critical role in the pathogenesis of vitiligo. Aquaporin-3 (AQP3), which is downregulated in vitiligo keratinocytes, regulates intracellular H₂O₂ accumulation. However, the role of AQP3 in oxidative stress is uncertain in vitiligo. This study investigated the effect of downregulated AQP3 on oxidative stress in vitiligo using lesional and non-lesional skin specimen sets from vitiligo patients and primary cultured adult normal human epidermal keratinocytes, with or without downregulation and overexpression of AQP3 in the presence or absence of H₂O₂ treatment. The levels of nuclear factor E2-related factor 2 (NRF2) and/or its main target, NAD(P)H quinone dehydrogenase 1 (NQO-1), were lower in the lesional keratinocytes and cultured keratinocytes with AQP3 knockdown, but were increased in keratinocytes upon AQP3 overexpression. Ratios of NRF2 nuclear translocation and NQO-1 expression levels were further reduced in AQP3-knockdown keratinocytes following H₂O₂ treatment. The conditioned media from AQP3-knockdown keratinocytes treated with H₂O₂ contained higher concentrations of reactive oxygen species (ROS). Moreover, the number of viable melanocytes was reduced when the conditioned media were added to the culture media. Overall, AQP3 downregulation in the keratinocytes of patients with vitiligo can induce oxidative stress in neighboring melanocytes, leading to melanocyte death.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.236-236
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• 2017

Low soil pH causes from $H^+$ rhizotoxicity results in nutrients unavailability in the growing media, inhibits plant growth, development and reduces crop yields. The present study was carried out to reveal morpholophysiological and biochemical responses of wheat (Triticum aestivum L.) to acidity stress. Four wheat varieties viz. BARI Wheat-21, BARI Wheat-25, BARI Wheat-26 and BARI Wheat-30 were used in the study. Eight-day-old seedlings were exposed to different pH levels (3.5, 4.5, 5.5 and 6.5) of growing media. Acidity stress at any level reduced biomass, water, and chlorophyll contents in all the varieties; whereas BARI Wheat-26 showed the least damage. $H^+$ rhizotoxicity also caused oxidative stress through excess production of reactive oxygen species and methylglyoxal which increase lipid peroxidation in all the varieties but the lowest oxidative damage was observed in BARI Wheat-26 due to better performance of the antioxidant defense and glyoxalase systems. Considering the growth, physiological and biochemical attributes BARI Wheat-26 may be considered as acidity stress tolerant, among the variety examined.

• 대한환경공학회지
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• 제33권2호
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• pp.85-92
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• 2011

본 연구에서는 산화망간과 산화철이 단독 및 복합 코팅된 반응성매질인 망간코팅사(MCS), 철코팅사(ICS) 그리고 철-망간코팅사(IMCS)를 이용하여 용존 Fe(II)의 산화 및 제거능을 평가하였다. 반응성매질에 $KMnO_4$와 NaOCl를 추가적인 산화제로 이용하였을 때의 Fe(II) 제거능을 반응용액의 pH, 반응시간, Fe(II) 농도변화에 따라 조사하였다. 반응성매질 및 추가적인 산화제 없이 Fe(II) 용액만을 사용한 경우, pH 5 이하에서는 Fe(II)의 느린 산화에 의해 제거율이 낮았으나 이후에는 빠른 산화 및 침전반응에 의해 제거율이 증가하였다. ICS만을 사용하였을 때 ICS 표면에 의한 Fe(II)의 제거는 극히 제한적인 것으로 나타났다. 망간 산화물이 코팅된 IMCS와 MCS를 사용한 경우 낮은 pH에서도 Fe(II)가 산화망간에 의해 산화되었으며 용액으로부터 효과적으로 제거되는 것으로 나타났다. Fe(II)는 IMCS만 단독으로 사용했을 때와 NaOCl을 산화제로 사용했을 때 제거율에서 큰 차이가 나지 않았다. IMCS와 산화제를 이용하여 Fe(II)을 제거할 경우, 용액의 pH가 증가함에 따라 이들의 산화능이 증가하였고 이로써 전체 제거율의 증가를 가져왔다. Fe(II)의 제거에 관한 반응속도 실험결과 유사-1차 반응 보다는 유사-2차 반응식으로 더 잘 표현되었으며 $KMnO_4$를 추가적인 산화제로 이용한 경우 Fe(II)는 14,286 mg/kg hr의 높은 초기 제거율(h)을 보였다. $KMnO_4$ 주입 시 반응시간 10분 안에 제거평형에 도달하였고 NaOCl의 경우는 6시간 후에 거의 제거평형에 도달하는 것으로 나타났다. IMCS에 의한 Fe(II)의 최대 제거량 값을 구하기 위해 pH 4에서 Langmuir 등온식에 적용한 결과 1,088 mg/kg의 제거량을 보였다.

• 한국축산식품학회지
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• 제36권1호
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• pp.8-13
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• 2016

This study investigated the effect of soy protein hydrolysates (SPH) prepared by varying subcritical media on the physicochemical properties of pork patties. For resource of SPH, two different soybean species (Glycine max Merr.) of Daewonkong (DWK) and Saedanbaek (SDB) were selected. SPH was prepared by subcritical processing at 190℃ and 25 MPa under three different of media (water, 20% ethanol and 50% ethanol). Solubility and free amino group content revealed that water was better to yield larger amount of SPH than ethanol/water mixtures, regardless of species. Molecular weight (Mw) distribution of SPH was also similar between two species, while slightly different Mw distribution was obtained by subcritical media. For pork patty application, 50% ethanol treatment showed clear red color comparing to control after 14 d of storage. In addition, ethanol treatment had better oxidative stability than control and water treatment based on thiobarbituric acid-reactive substances (TBARS) analysis. For eating quality, although 20% ethanol treatment in SDB showed slightly higher cooking loss than control, generally addition of SPH did not affect the water-binding properties and hardness of pork patties. Consequently, the present study indicated that 50% ethanol was the best subcritical media to produce SPH possessing antioxidant activity, and the SPH produced from DWK exhibited better antioxidant activity than that produced SDB.

• 동의생리병리학회지
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• 제17권3호
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• pp.662-665
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• 2003

To examine the cytotoxicity of reactive oxygen species in cultured rat myocardial cells, cytotoxic effect was determined by MTT assay after cultured cells were incubated for 4 hours in the media containing 1～30μM of H₂O₂. And also, the protective effect of Drynariae Rhizoma(DR) was determined in these cultrures. Cell viability was significantly decreased in a dose-dependent manner after exposure of 15 μM H₂O₂ to cultured rat myocardials for 4 hours. In the protective effect of DR, DR prevented the H₂O₂-induced cytotoxicity in these cultures. From these results, it suggests that H₂O₂ has toxic effect in cultured mouse myocardial cells and DR has protective effect on the cytotoxicity induced by H₂O₂.

• 동의생리병리학회지
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• 제17권5호
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• pp.1305-1308
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• 2003

To evaluate the neurotoxicity of reactive oxygen species (ROS) in cultured cultured spinal dorsal root(DRG) neurons derived from neonatal mouse, Cytotoxicity was measured by MTS assay after cultured cells were grown for 3 hours in the media containing 1～60 μM hydrogen peroxide (H₂O₂). In addition the neuroprotective effect of Salviae Miltiorrhzae Radix (SMR) was measured in these cultrures. Cell viability was positively decreased in a dose- and time-dependent manner after exposure of cultured mouse DRG neurons to 30 tt M H202 for 3 hours. In the neuroprotective effect of SMR on H₂O₂-mediated toxicity, SMR prevented the H₂O₂-induced neurotoxicity in these cultures. From these results. it suggests that H₂0₂ is toxic in cultured mouse spinal motor neurons and selective herb extract such as Uncariae Ramulus Cum Uncis is effective in prevetion of the neurotoxicity induced by H₂O₂.

• 동의생리병리학회지
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• 제17권2호
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• pp.499-502
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• 2003

Neurotoxicity of reactive oxygen species(ROS) and neuroprotective effect of Aconiti Radix(AR) against ROS-induced cytotoxicity were determined on cultured mouse cerebral neurons by MTT assay after cerebral neurons were cultured for 5 hours in various concentrations of GO. GO was toxic in a dose-dependent manner on cultured cerebral neurons after cerebral neurons were incubated for 5 hours in media containing 5～40mU/ml GO. While, cultures were pretreated with 180 μg/ml AR for 2 hours increased remarkably cell viability. From these results, it is suggested that GO has toxic effect on cultured mouse cerebral neurons by the decrease of cell viability. And also, herb extract such as AKR is very effective in the protection pf neurotoxicity induced by GO.

• 정보저장시스템학회논문집
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• 제3권4호
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• pp.173-177
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• 2007

A photo-reactive methacrylate monomer having triazine as a core component was examined for photochromic diffractive image formation. Photochromic photopolymer films as a recording media contained a monomer mixture of triazine difunctional metharylate (DT) and ethylene glycol phenyl ether acrylate, binder polymer, photo initiator, and a photochromic spiro-oxazine dye. The content of photochromic dye was changed to examine the effect of photochromophore on diffraction efficiency and real holographic image formation. Holographic recording was performed on the photopolymer film by the combination of reference and probe beam. The diffraction efficiency of the photopolymer film in real-time measurement reached a maximum of $\sim90%$ within 30s. It was highly dependent on the photochromophore contents. After holographic recording, the color of the recorded area was changed under UV light (365 nm) and reversibly bleached to original color upon exposure to a visible light source. Films containing only photochromophore without monomer mixture were not reactive under the recording beam (491nm). Diffractive image formation and mechanism of the holographic recording in the presence of photochromophore will be presented.

• 한국HCI학회논문지
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• 제9권1호
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• pp.23-28
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• 2014

In this study we focus on the effect of the interaction between humans and reactive television when emotion recognition through facial expression mechanism is used. Most of today's user interfaces in electronic products are passive and are not properly fitted into users' needs. In terms of the user centered device, we propose that the emotion based reactive television is the most effective in interaction compared to other passive input products. We have developed and researched next generation cognitive TV models in user centered. In this paper we present a result of the experiment that had been taken with Fraunhofer IIS $SHORE^{TM}$ demo software version to measure emotion recognition. This new approach was based on the real time cognitive TV models and through this approach we studied the relationship between humans and cognitive TV. This study follows following steps: 1) Cognitive TV systems can be on automatic ON/OFF mode responding to motions of people 2) Cognitive TV can directly select channels as face changes (ex, Neutral Mode and Happy Mode, Sad Mode, Angry Mode) 3) Cognitive TV can detect emotion recognition from facial expression of people within the fixed time and then if Happy mode is detected the programs of TV would be shifted into funny or interesting shows and if Angry mode is detected it would be changed to moving or touching shows. In addition, we focus on improving the emotion recognition through facial expression. Furthermore, the improvement of cognition TV based on personal characteristics is needed for the different personality of users in human to computer interaction. In this manner, the study on how people feel and how cognitive TV responds accordingly, plus the effects of media as cognitive mechanism will be thoroughly discussed.