• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.285-286
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• 2003

다단임팩터(cascade impactor)는 대기환경 연구에 있어 입자상물질의 물리ㆍ화학적 분석에 유용하게 사용되고 있는 입자상물질 포집장치이다. 본 연구그룹에서는 분리입경이 각각 10.07, 4.92, 2.49, 1.02, 0.7$\mu\textrm{m}$인 5단 다단임팩터를 이미 개발하여 성능평가를 수행하였으며, 그 연구결과를 발표하였다(Kwon et al., 2003). 또한 개발된 임팩터를 2002년 4월 8일 부터 29일까지 제주도 고산지역에서 실시된 ACE-Asia 측정 기간동안 설치 운영하여 대기 중 에어로졸 샘플링을 하였다(Park et al., 2003). 본 연구에서는 다단임팩터 사용자의 불편을 최소화하고, 장치의 상용화가 가능하도록 최적 설계에 주안점을 두었다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.354-355
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• 2002

Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia) Project의 1차 집중 관측기간 중에 2001년 4월 4일부터 일주일 동안 제주도 고산에서 채취한 시료에 대하여 low-Z electron probe X-ray microanalysis (low-Z EPMA)를 이용한 입자상물질의 단일 입자 분석을 수행하였다. 시료채취 장소인 제주도는 대기 중 입자상물질에 대한 대륙과 해양의 영향을 연구하는데 이상적인 장소이다 왜냐하면 제주로는 한반도, 중국대륙, 일본, 그리고 황해로 둘러 쌓여있어서 대륙간의 영향을 많이 받지만 그 자체가 청정지역이라 측정결과의 해석이 용이하기 때문이다. (중략)

• The Journal of Internal Korean Medicine
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• v.29 no.4
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• pp.988-999
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• 2008

Objectives : The study was conducted to evaluate antioxidative, anti-atherosclerotic and anti-hypertensive effects of natural remedies. Alisma Rhizome (AR) has been used for a long time in Asia in folk remedies for treatment of hypertension and stroke and has been used in Korean traditional medicine for the treatment of glycosuria, gonorrhea, hypercholesterolemia, hypertension, and jaundice and its diuretic effect. These pharmacological effects of AR might come from antioxidant properties of phytochemicals in these materials. Methods : In this study, the antioxidant activity of extract from AR was studied with in vitro methods by measuring the antioxidant activity by TEAC, measuring the scavenging effects on reactive oxygen species (ROS) [superoxide anion, hydroxyl radical] and on reactive nitrogen species (RNS) [nitric oxide and peroxynitrite] as well as measuring the inhibitory effect on $Cu^{2+}$ induced human LDL oxidation and on ACE. Results : The AR extracts were found to have a potent scavenging activity, as well as an inhibitory effect on LDL oxidation and on ACE against all of the reactive species tested, with the water extract showing particularly strong antioxidant activities. Conculsions : The AR extracts have antioxidative, anti-atherosclerotic and anti-hypertensive effects in an in vitro system, which can be used for developing pharmaceutical drugs against oxidative stress and atherosclerosis.

• Journal of the Korean Society of Food Culture
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• v.19 no.1
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• pp.94-105
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• 2004

The biochemical components of Namcheondlggae, Miryangdlkkae 25, Boradlggae and Ipdlkkae 1 were measured. The samples were extracted with hot water, 60% acetone or 80% ethanol for screening physiological activity. The crude protein content (4.36%) was found in the Miryangdlkkae 25 and calcium content (497.5 mg%) was found in the Namcheondlggae among the tested 4 perilla loaves. Fructose was 30.86 mg% in the Namcheondlggae and free amino acids at all perilla leaves was detected seventeen. In Boradlggae, glutamic acid and alanine were 25.37 and 11.91 mg%. Totally nine non-volatile organic acids were also detected and the contents of malic acid and glutaric acid were 28.34 and 14.57 mg% in Boradlggae. The Miryangdlkkae 25 had the highest vitamin C amount which was 113.24 mg%. Angiotensin converting enzyme (ACE) inhibition activity of 60% acetone extract of Miryangdlkkae 25 was 39.20% when added as addition of 200 ppm level and xanthine oxidase inhibition activity of 80% ethanol extract of Boradlggae was 46.71%. Electron denoting activity of 60% acetone extract from Namcheohndlggae was the strongest inhibition activity as 98.19% when 200 ppm level of the sample extracts were added.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.232-235
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• 2003

In general, the parameters of climate change include aerosol chemical compounds, aerosol optical depth, greenhouse gases(carbon dioxide, CFCs, methane, nitrous oxide, tropospheric ozone), ozone distribution, precipitation acidity and chemical compounds, persistent organic pollutants and heavy metals, radioactivity, solar radiation including ultra-violet and standard meteorological parameters. Over the last ten years, the monitoring activities of Korea regarding to the climate change have been progressed within the WMO GAW and ACE-Asia IOP programs centered at the observation sites of Anmyeon and Jeju Gosan islands respectively. The Greenhouse gases were pointed out that standard air quality monitoring techniques are required to enhance data comparability and that data presentation formats need to be harmonized and easily understood. Especially, the impact of atmospheric aerosols on climate depends on their optical properties, which, in turn, are a function of aerosol size distribution and the spectral reflective indices. Aerosol optical depth and single scattering albedo in the visible are used as the two basic parameters in the atmospheric temperature variation studies. The former parameter is an indicator of the attenuation power of aerosols, while the latter represents the relative strength of scattering and absorption by aerosols. For aerosols with weak absorption, surface temperature decreases as the optical depth increases because of the domination of backscattering. For aerosols with strong absorption, however, warming could occur as the optical depth increases. The objective of the study is to characterize the means, variability, and trends of Greenhouse gases and aerosol properties on a regional basis using data from its baseline observatories in Korea peninsula. A further goal is to understand the factors that control radiative forcing of the greenhouse and aerosol.

• Child Studies in Asia-Pacific Contexts
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• v.7 no.1
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• pp.15-26
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• 2017

The aim of this study was to retrospectively estimate the prevalence of childhood emotional abuse (CEA), childhood physical abuse (CPA), and childhood contact sexual abuse (CCSA) in relation to adult poor mental health, addictive behavior, and other health-risk behaviors among university students in five ASEAN countries (Indonesia, Malaysia, Myanmar, Thailand, and Vietnam). In a cross-sectional survey, 3,240 undergraduate university students were randomly selected (M age = 20.5 years, SD = 1.6 years) to respond to a questionnaire including the Abuse section of the World Health Organization (WHO) Version 1 "Adverse Childhood Experiences International Questionnaire" (ACE-IQ) and other measures. The students reported 17.9% CEA, 28.2% CPA, and 22.4% CCSA, with the highest prevalence of CEA in Myanmar (30.9%) and CPA and CCSA in Vietnam (55.8% and 41.6%, respectively). In logistic regression models, adjusting for sociodemographic and social variables, the separate and cumulative effects of three types of child abuse (emotional, physical, and sexual) were found to increase the risks for poor adult mental health, addictive, and other health-risk behaviors.

• Korean Journal of Pharmacognosy
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• v.49 no.3
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• pp.240-245
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• 2018

The fruits of Eleutherococcus sessiliflorus (Rupr. & Maxim.) S. Y. Hu (Araliaceae), as edible fruits, were traditionally used for ingredients of wine or tea in Eastern Asia. In addition to, the fruits of E. sessiliflorus were known for having antioxidant and anti-inflammatory effects. Recently, we investigated that the ethanolic extracts of E. sessiliflorus fruits (DHP1501) have effects on hypertension via vasorelaxation and decrease of blood pressure. In the present study, we investigated that the gene and protein expression levels of endothelial nitric oxide synthase (eNOS) was increased by treatment of DHP1501 in HUVECs. Moreover, we confirmed the angiotensin converting enzyme inhibitory activity of DHP1501 through in vitro tasks. Therefore, DHP1501 could be a candidate of functional food for alleviating hypertension.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.04a
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• pp.55-56
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• 2006

This thesis describes the use of measured aerosol size distributions and size-resolved hygroscopic growth to examine the physical and chemical properties of several particle classes. The primary objective of this work was to investigate the optical and cloud forming properties of a range of ambient aerosol types measured in a number of different locations. The tool used for most of these analyses is a differential mobility analyzer / tandem differential mobility analyzer (DMA / TDMA) system developed in our research group. To collect the data described in two of the chapters of this thesis, an aircraft-based version of the DMA / TDMA was deployed to Japan and California. The data described in two other chapters were conveniently collected during a period when the aerosol of interest came to us. The unique aspect of this analysis is the use of these data to isolate the size distributions of distinct aerosol types in order to quantify their optical and cloud forming properties. I used collected data during the Asian Aerosol Characterization Experiment (ACE-Asia) to examine the composition and homogeneity of a complex aerosol generated in the deserts and urban regions of China and other Asian countries. An aircraft-based tandem differential mobility analyzer was used for the first time during this campaign to examine the size-resolved hygroscopic properties of particles having diameters between 40 and 586 nm. Asian Dust Above Monterey (ADAM-2003) study was designed both to evaluate the degree to which models can predict the long-range transport of Asian dust, and to examine the physical and optical properties of that aged dust upon reaching the California coast. Aerosol size distributions and hygroscopic growth are measured in College Station, TX to investigate the cloud nucleating and optical properties of a biomass burning aerosol generated from fires on the Yucatan Peninsula. Measured aerosol size distributions and size-resolved hygroscopicity and volatility were used to infer critical supersaturation distributions of the distinct particle types that were observed during this period. The predicted CCN concentrations were used in a cloud model to determine the impact of the different aerosol types on the expected cloud droplet concentration. RH-dependent aerosol extinction coefficients are calculated at a wavelength of 550 nm.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.E3
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• pp.137-148
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• 2003

In this study, we examined the influence of long-range transport of dust particles and air pollutants on the photochemistry of NO$_3$on Jeju Island, Korea (33.17 N, 126.10$^{\circ}$E) during the Asian Dust-Storm (ADS) period of April 2001. Three ADS events were observed during the periods of 10∼12, 13∼14, and 25∼26 April. Average concentration level of nighttime NO$_3$on Jeju Island during the ADS period was estimated to be about 2 x 10$^{8}$ molecules cm$^{-3}$ ( - 9 pptv). Decreases in NO$_3$levels during the ADS period was likely to be determined mainly by the enhancement of the $N_2$O$_{5}$ heterogeneous reaction on dust aerosol surfaces. The reaction of N20s on aerosol surfaces was a more important sink for nighttime N03 during the ADS due to the significant loading of dust particles. The reaction of $N_2$O$_{5}$ with NMHCs and the gas-phase reaction of N20s with water vapor were both significant loss mechanisms during the study period, especially during the NADS. However, dry deposition of these oxidized nitrogen species and a heterogeneous reaction of NO$_3$were of no importance. Short-term observations of $O_3$, NO$_2$, DMS, and SO$_2$in the MBL indicated that concentrations of most of these chemical species were different between the ADS and non - Asian - Dust-Storm (NADS) periods, implying that their levels were affected sensitively by the differences in air mass trajectories.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.423-423
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• 2003

The radiative properties of atmospheric aerosol are determined by the mass and chemical characteristics, and optical properties such as aerosol optical depth (AOD), ngstr m parameter ( $\alpha$) and single scattering albedo (SSA). In particular these aerosol optical properties also determine surface temperature perturbation that may give some information in understanding the regional atmospheric radiative forcing. For understanding the radiative forcing and regional surce of aerosol, this paper summarizes and compares the aerosol optical properties results from and compares the atmospheric aerosol optical properties results from two different experiments: Anmyeon 2000 and Jeju 2001. Korea Global Atmosphere Watch Observatory (KGAWO) at Anmyeon island and ACE-Asia super-site at Gosan Jeju island have measured the radiations and aerosols since the year of 2000. The sites are located in the mid-west and south of Korea peninsula where it is strongly affected by the Asian dust coming from China region in every spring. Aerosol optical properties over both sites were measured through the ground-based sun and sky radiometers were analyzed for understanding the radiation and climate properties. Number concentration and chemical components of aerosol were additionally analyzed for the source estimation in the transportation. The frequency distributions of aerosol optical depth are rather narrow with a modal vaiue of 0.38 at both sites. However, the distributions of show one peak (1.13) at Jeju but two peaks (0.63 and 1.13) at Anmyeon. In the cases of Anmyeon, one peak around 0.63 corresponds to relatively dust-free cases, and the second peak around 1.13 characterizes the situation when Asian dust is presented. The correlation between AOD and resulted high correlation on the wide range with high values of optical depth at Anmyeon, otherwise a narrow range of with moderate to low AOD at Jeju. In dust free condition SSA decrease with waveleneth while in the presence of Asian dust SSA either stays neutral or increases slightly with wavelength. The change of surface temperature shows the stronger positive correlations with aerosol optical depth increase at Anmyeon than Jeju. In the chemical properties the aerosol are related to high concentrations in inorganic matters, SO$^4$, NO$_3$, CA2+ in fine and coarse.