• Title/Summary/Keyword: concentration measure

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A Study on Serum Concentrations of Antioxidant Minerals in Normal Korean Adults (한국 정상성인의 항산화 관련 혈청 무기질 농도에 관한 연구)

  • 이양자
    • Journal of Nutrition and Health
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    • v.31 no.3
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    • pp.324-332
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    • 1998
  • Studies on relationships between antioxidant nutrients and various chronic diseases are increasing. In this study , serum concentrations of antioxidant minerals(Se, Cu, Zn & Mn) wee measured and compared among normal Korean adults. The ICP -MS method was employed to measure mineral concentrations. The subjects consisted of 329 healthy adults(154 men & 175 women) aged 20-79 years. The mean serum concentration appeared to be 26.4$\pm$0.41 (Se), 89.6$\pm$1.53(Cu), 113.3$\pm$1.56(Zn) & 0.34$\pm$0.05(Mn)$\mu\textrm{g}$/㎗ for men and 24.5$\pm$0.32(Se), 95.1$\pm$1.58(Cu), 133.6$\pm$1.79(Zn) & 0.35$\pm$0.02(Mn) $\mu\textrm{g}$/㎗ for women respectively. Among antioxidant minerals measured, the mean serum levels of Se and Zn were higher in men than in women(p<0.001), whereas that of Cu was higher in women(p<0.01). No significant difference between sex was observed for the mean Mn concentrations. The mean serum levels of Se(p<0.01) and Zn(p<0.05) decreased significantly in the 60's women On the other hand, the Mn concentrations in the 60's of women showed a significant increase(p<0.01). This difference seems to be due to the changes in menopausal status . The Cu levels in men showed a consistent increase with advancing age. The mean Cu/Zn ratios were 0.83 $\pm$0.04 for men and 0.95$\pm$0.02(p<0.01) for women respectively. The fact that this ratio increased significantly at the 60's of men (1.26 ; p<0.001) requires further study in relation to chronic diseases. When analyzed by stepwise multiple regression, drinking positively influenced serum Se and Cu levels for both men and women , smoking, however, negatively influenced all serum mineral levels for women. Further studies are needed to clarify precise roles of antioxidant minerals, their interactions and their relation to disease status.

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Measuring Socioeconomic Disparities in Cancer Incidence in Tehran, 2008

  • Rohani-Rasaf, Marzieh;Moradi-Lakeh, Maziar;Ramezani, Rashid;Asadi-Lari, Mohsen
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.6
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    • pp.2955-2960
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    • 2012
  • Background: Health disparities exist among and within countries, while developing and low income countries suffer more. The aim of this study was to quantify cancer disparities with regard to socioeconomic position (SEP) in 22 districts of Tehran, Iran. Method: According to the national cancer registry, 7599 new cancer cases were recorded within 22 districts of Tehran in 2008. Based on combined data from census and a population-based health equity study (Urban HEART), socioeconomic position (SEP) was calculated for each district. Index of disparity, absolute and relative concentration indices (ACI & RCI) were used for measuring disparities in cancer incidence. Results: The overall cancer age standardised rate (ASR) was 117.2 per 100,000 individuals (120.4 for men and 113.5 for women). Maximum ASR in both genders was seen in districts 6, 3, 1 and 2. Breast, colorectal, stomach, skin and prostate were the most common cancers. Districts with higher SEP had higher ASR (r=0.9, p<0.001). Positive ACI and RCI indicated that cancer cases accumulated in districts with high SEP. Female disparity was greater than for men in all measures. Breast, colorectal, prostate and bladder ASR ascended across SEP groups. Negative ACI and RCI in cervical and skin cancers in women indicate their aggregation in lower SEP groups. Breast cancer had the highest absolute disparities measure. Conclusion: This report provides an appropriate guide and new evidence on disparities across geographical, demographic and particular SEP groups. Higher ASR in specific districts warrants further research to investigate the background predisposing factors.

Surface Cover Application for Reduction of Runoff and Sediment Discharge from Sloping Fields (경사지 밭에서 발생하는 토양유실 저감을 위한 피복재 적용)

  • Shin, Min-Hwan;Won, Chul-Hee;Park, Woon-Ji;Choi, Young-Hun;Shin, Jae-Young;Lim, Kyoung-Jae;Choi, Joong-Dae
    • Journal of The Korean Society of Agricultural Engineers
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    • v.53 no.6
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    • pp.129-136
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    • 2011
  • To measure effects of surface cover on runoff and sediment discharge reduction using rainfall simulator, four(5 m${\times}$30 m scale) plot experiments were conducted in this study. Surface covers made with straw mat, Polyacrylamide (PAM), chaff, and sawdust were simulated 4 times under 31.1~44.4 mm/hr rainfall intensities. Compared with results from control plot, the time of runoff generation is delayed and outflow volume decreased with surface cover. Effects on runoff reduction of straw mat, PAM, sawdust and chaff ranged 4.7~81.5 % and runoff rate reduced by 6.5~76.1 % respectively, when compared with those from control plot. The percentage of decrease in sediment discharge were 99.7~99.8 % from straw mat+sawdust+PAM plots, 85.9~95.6 % from straw mat+PAM plots, and 98.5~99.4 % from straw mat+chaff+PAM plots. The runoff, sediment discharge, and SS concentration reduction efficiencies of the cover materials were outstanding when compared to control plot. It was analyzed that reduction of runoff and sediment discharge were mainly contributed by decrease in rainfall energy impact and flow velocity and increase of infiltration due to the surface cover materials. The results could be used as a base for the development of best management practices (BMPs) to reduce runoff, sediment discharge from sloping field.

Temporal Variability of Reduced Sulfur Compounds (RSC) Collected in Tedlar Bag: Simulation of Sample Stability in the Emission Sources (배출원에서의 Tedlar-bag 시료채집법을 이용한 황화합물의 경시적 농도 변화에 대한 연구)

  • Jo, Hyo-Jae;Shon, Zang-Ho;Hong, One-Feel;Kim, Ki-Hyun
    • Journal of Korean Society for Atmospheric Environment
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    • v.27 no.3
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    • pp.281-290
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    • 2011
  • In this study, a series of experiments were carried out to measure temporal stability of reduced sulfur compounds (RSCs) in Tedlar bag samples as a function of elapsed storage time. To this end, temporal variability of 4 RSC standard gases ($H_2S$, $CH_3SH$, DMS, DMDS) was measured up to 29 days. For the purpose of comparison, RSC samples were stored in both individual and mixed state. In the case of mixed standard, samples were also examined to allow comparison between light and dark condition. Then results of $CH_3SH$ data were the most stable with the least change in its concentrations through the end of exps (29 days). When compared with previous studies, the extent of stability appeared to be influenced by the initial concentration levels of samples. When the patterns were compared between individual and mixture samples, differences were not significant in the case of $H_2S$ and DMS. The effects of light conditions on temporal stability were seen to be fairly sensitive on most RSC other than $H_2S$. The results of our study confirm that the stability of RSC storage is affected by their involvement in photochemical reactions.

Maximizing Biomass Productivity and $CO_2$ Biofixation of Microalga, Scenedesmus sp. by Using Sodium Hydroxide

  • Nayak, Manoranjan;Rath, Swagat S.;Thirunavoukkarasu, Manikkannan;Panda, Prasanna K.;Mishra, Barada K.;Mohanty, Rama C.
    • Journal of Microbiology and Biotechnology
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    • v.23 no.9
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    • pp.1260-1268
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    • 2013
  • A series of experiments were carried out with three native strains of microalgae to measure growth rates, biomass, and lipid productivities. Scenedesmus sp. IMMTCC-6 had better biomass growth rate and higher lipid production. The growth, lipid accumulation, and carbon dioxide ($CO_2$) consumption rate of Scenedesmus sp. IMMTCC-6 were tested under different NaOH concentrations in modified BBM. The algal strain showed the maximum specific growth rate (0.474/day), biomass productivity (110.9 mg $l^{-1}d^{-1}$), and $CO_2$ consumption rate (208.4 mg $l^{-1}d^{-1}$) with an NaOH concentration of 0.005 M on the $8^{th}$ day of cultivation. These values were 2.03-, 6.89-, and 6.88-fold more than the algal cultures grown in control conditions (having no NaOH and $CO_2$). The $CO_2$ fixing efficiency of the microalga with other alternative carbon sources like $Na_2CO_3$ and $NaHCO_3$ was also investigated and compared. The optimized experimental parameters at shake-flask scale were implemented for scaling up the process in a self-engineered photobioreactor. A significant increase in lipid accumulation (14.23% to 31.74%) by the algal strain from the logarithmic to stationary phases was obtained. The algal lipids were mainly composed of $C_{16}/C_{18}$ fatty acids, and are desirable for biodiesel production. The study suggests that microalga Scenedesmus sp. IMMTCC-6 is an efficient strain for biodiesel production and $CO_2$ biofixation using stripping solution of NaOH in a cyclic process.

The Study to ETS Exposure and Their Biomarkers in Hair of Restaurant Workers (식당 종업원의 환경 담배 연기(ETS)의 노출과 머리카락 중 생체지표 연구)

  • Jo Seong-Joon
    • Environmental Analysis Health and Toxicology
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    • v.19 no.2
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    • pp.169-176
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    • 2004
  • ETS (environmental tobacco smoke) is composed of exhaled mainstream smoke (MS) from the smoker, sidestream smoke (SS) emitted from the smoldering tobacco between puffs and contaminants that diffuse through the cigarette paper and mouth between puffs. These emissions contain both vapor phase and particulate contaminants. ETS is a complex mix of over 4,000 compounds. This mix contains many known or suspected human carcinogens and other toxic agents. More of these toxic compounds are found in SS than in MS. Workplace exposure to ETS can result in significant smoke intake, and passive smoke exposure may be related to impair respiratory function and an increase risk of lung cancer in nonsmokers. For nonsmokers sharing a work environment with cigarette smokers, the workplace must be considered hazardous independently of any specific industrial toxic exposure. The risk is particularly important when a high percentage of the workers smoke or where smokers and nonsmokers work in poorly ventilated areas. Nicotine is converted in the body to cotinine; cotinine therefore can be used as an indirect measure of a person's recent exposure to tobacco smoke. Levels of nicotine in hair and levels of cotinine in body fluids (saliva and urine) have been shown to increase with increasing environmental nicotine levels and with self-reported ETS exposure. The measurement of nicotine or cotinine in hair may be more appropriate for longer-term exposure to tobacco. The purpose of this study is to comparing airborne nicotine levels and hair cotinine level in restaurant workers. Concentration of airborne nicotine and hair nicotine (and cotinine) is closely related to exposed frequency of sidestream smoke in the workplace. Nicotine in hair is a better predictor of airborne nicotine than hair cotinine. Hair nicotine can be a useful tool to assess ETS exposure interventions. It may have limiting levels of ETS exposure by placing regulatory restrictions on smoking in workplaces and in public spaces.

A Study on the Deduction of Social Issues Applying Word Embedding: With an Empasis on News Articles related to the Disables (단어 임베딩(Word Embedding) 기법을 적용한 키워드 중심의 사회적 이슈 도출 연구: 장애인 관련 뉴스 기사를 중심으로)

  • Choi, Garam;Choi, Sung-Pil
    • Journal of the Korean Society for information Management
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    • v.35 no.1
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    • pp.231-250
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    • 2018
  • In this paper, we propose a new methodology for extracting and formalizing subjective topics at a specific time using a set of keywords extracted automatically from online news articles. To do this, we first extracted a set of keywords by applying TF-IDF methods selected by a series of comparative experiments on various statistical weighting schemes that can measure the importance of individual words in a large set of texts. In order to effectively calculate the semantic relation between extracted keywords, a set of word embedding vectors was constructed by using about 1,000,000 news articles collected separately. Individual keywords extracted were quantified in the form of numerical vectors and clustered by K-means algorithm. As a result of qualitative in-depth analysis of each keyword cluster finally obtained, we witnessed that most of the clusters were evaluated as appropriate topics with sufficient semantic concentration for us to easily assign labels to them.

A Study on the Development of the Mercury Emission Factor from Coal-fired Power Plant (석탄 화력발전시설에서의 수은 배출계수 개발에 관한 연구)

  • Kim, Hyung-Chun;Park, Jung-Min;Jang, Kee-Won;Lee, Sang-Bo;Jung, No-El;Song, Deok-Jong;Hong, Ji-Hyung;Lee, Suk-Jo;Kim, Sang-Kyun
    • Journal of Korean Society for Atmospheric Environment
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    • v.28 no.2
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    • pp.172-181
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    • 2012
  • Mercury is one of the most hazardous air pollutants. Recently, mercury has been a concern in domestic and overseas because it has lethal toxicity, long distance transport, persistence and bioaccumulation in the environment. Stationary combustion sources such as coal-fired power plants, waste incinerators, and cement kilns are the major sources of mercury emissions. The objectives of this study were to measure the concentration for mercury from coal-fired power plants and to calculate emission factor to estimate its emission. The results showed that the mercury concentrations in the flue gas were 1.63-3.03 mg/$Sm^3$ in anthracite-fired power plants (average 2.32 mg/$Sm^3$) and 1.95-3.33 mg/$Sm^3$ in bituminous-fired power plants (average 2.6 mg/$Sm^3$). Mercury emission factor was estimated as 25.74 mg/ton for anthracite-fired power plants and 12.48 mg/ton for bituminous-fired power plants. Because actual measurements are limited in quantity, it is desirable to refine our estimates by extending the actual measurements.

Spatial and Temporal Assessment of Particulate Matter Using AOD Data from MODIS and Surface Measurements in the Ambient Air of Colombia

  • Luna, Marco Andres Guevara;Luna, Fredy Alejandro Guevara;Espinosa, Juan Felipe Mendez;Ceron, Luis Carlos Belalcazar
    • Asian Journal of Atmospheric Environment
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    • v.12 no.2
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    • pp.165-177
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    • 2018
  • Particulate matter (PM) measurements are important in air quality, public health, epidemiological studies and decision making for short and long-term policies implementation. However, only few cities in the word have advance air quality-monitoring networks able to provide reliable information of PM leaves in the ambient air, trends and extent of the pollution. In Colombia, only major cities measure PM concentrations. Available measurements from Bogota, Medellin and Bucaramanga show that PM concentration are well above World Health Organization guidelines, but up to now levels and trends of PM in other cities and regions of the country are not well known. Satellite measurements serve as an alternative approach to study air quality in regions were surface measurements are not available. The aim of this study is to perform a spatial and temporal assessment of PM in the ambient air of Colombia. We used Aerosol optical depth (AOD) retrieved by the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite of NASA and surface measurements from the air quality networks of Bogota, Medellin and Bucaramanga. In a first step, we estimated the correlation between MODIS-AOD and monthly average surface measurements (2000 to 2015) from these three cities, obtaining correlation coefficient R values over 0.4 for the cities under study. After, we used AOD and $PM_{10}$ measurements to study the temporal evolution of PM in different cities and regions. Finally, we used AOD measurements to identify cities and regions with the highest AOD levels in Colombia. All the methods presented in this paper may serve as an example for other countries or regions to identify and prioritize locations that require the implementation of more accurate air quality measurements.

Development of mobile user fatigue measurement system using smart wearable device (스마트 웨어러블 디바이스를 이용한 모바일 기반 사용자 피로도 측정 시스템 개발)

  • Kim, Na Yeon;Kim, Dong Keun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.12
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    • pp.2357-2364
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    • 2017
  • Recently, smart wearable devices for monitoring health status have been utilized as interest in health care has increased. In this paper, we developed a fatigue measurement system that works with smart wearable devices. Unlike physical fatigue that is restored when you take enough rest, mental fatigue can decrease the efficiency or concentration of work, so you can monitor your mental health status through measurements. This system provides the function to transmit the measured data from the smart wearable device to the smartphone and to calculate the mental fatigue. A fatigue index was developed to measure fatigue and expressed as a number from 1 to 5. In addition, the results of the fatigue calculation and the survey were compared with the results of the independent sample t-test. Therefore, this system will be used to help users manage their health efficiently.