• Title/Summary/Keyword: Mass standards

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A Study on Home Accidents of Preschool Children (from 1 to 6) in Korea and Prevention Measures (영유소아기 가정사고의 원인과 예방에 관한 연구)

  • 변수자
    • Journal of Korean Academy of Nursing
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    • v.4 no.1
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    • pp.107-120
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    • 1974
  • Necessity and purpose of this study: In a large number of countries it has been founded that children′s domestic accidents are at great risk year by year In the United States, they publish detailed accident statistics at regular intervals. In Korea. there have been just a few studies on Accidents-At-Home of preschool children. But it can not be said that there have been any systematic statistics about this area. and any study accounting for the relations of home accidents and preschool: children in detail, Therefore, the purpose of this thesis was focused on the inquire of these relations so as to make a little contribution to Korean preschool children′s health and security measures. So, the detail-purposes are to study following questions and to testify following hypothesis. Prob. 1. What the types of accidents of Preschool children, where the place accidents occurred\ulcorner Prob. 2. What the cause of accidents and, the main factors of the cause\ulcorner Prob. 3. How about the number of their children. the disparity of age among their children and mother′s age in each case of accidents\ulcorner hypothesis 1. There will be differences in the density of protection of parents according to the number of their children. hypothesis 2, There will be differences in accident-types and first-aid methods according to parents socio-economic background. Method; This study employed the interviewing survey method, in which 130 preschool children ware random.sampled, who visit hospital to have medical care. These children (from 1 to 6 years olds) were selected at the emergency room of five hospitals in Seoul (Hosp: Severance, Woosok, Medical Center, Hanyang Medical College Hospital and Seoul Medical Col1age Hospital during study-period (from Aug. to Oct, 1973). Four head nurses in above Hospitals were employed as accident members for this study. Concerning research analysis, the method of hypothesis verifying is used. Conclusion: As two American experts on this subject. Dr, Raymond Neuter and Mr. Ross Mc Garland have drawn attention to "minor epidemics of accidents" that could be avoided by fairly simple measures. preschool children′s accidents could be avoided by parents fair attentions. In other words, one of the most common causes of preschool children′s accidents derived from their parent′s inattention. Therefore, one important task on this subject is to instruct the parents fairly about the children′s accidents. Many accidents could be avoided by the exorcist of a little self-discipline. Also, as much the prevention of accidents is important, as the first-aid Is Important and necessary at the case of the accidents. So, the methods of proper first-aid treatment must be emphasized, and must be taught in school, especially in girls school. And there could be other means available for prevention of accidents. Firstly, the public authorities can take legal measures. More stringent safety standards can be made enforceable by law. Building materials and equipment for domestic us: ought to meat minimum safety criteria at all times. Next the public itself has to understand the seriousness of the problem, and here the dissemination of information is of great importance. All mass media should be brought into play to promote greater public awareness of the question. At last, it will be needed to obtain more detailed epidemiological data through additional surveys and statistics after this study.

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Acute Pulmonary Toxicity and Body Distribution of Inhaled Metallic Silver Nanoparticles

  • Kwon, Jung-Taek;Minai-Tehrani, Arash;Hwang, Soon-Kyung;Kim, Ji-Eun;Shin, Ji-Young;Yu, Kyeong-Nam;Chang, Seung-Hee;Kim, Dae-Seong;Kwon, Yong-Taek;Choi, In-Ja;Cheong, Yun-Hee;Kim, Jun-Sung;Cho, Myung-Haing
    • Toxicological Research
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    • v.28 no.1
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    • pp.25-31
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    • 2012
  • The purpose of this study was to determine the acute pulmonary toxicity of metallic silver nanoparticles (MSNPs, 20.30 nm in diameter). Acute pulmonary toxicity and body distribution of inhaled MSNPs in mice were evaluated using a nose-only exposure chamber (NOEC) system. Bronchoalveolar lavage (BAL) fluid analysis, Western blotting, histopathological changes, and silver burdens in various organs were determined in mice. Mice were exposed to MSNPs for 6 hrs. The mean concentration, total surface area, volume and mass concentrations in the NOEC were maintained at $1.93{\times}10^7$ particles/$cm^3$, $1.09{\times}10^{10}\;nm^2/cm^3$, $2.72{\times}10^{11}\;nm^3/cm^3$, and 2854.62 ${\mu}g/m^3$, respectively. Inhalation of MSPNs caused mild pulmonary toxicity with distribution of silver in various organs but the silver burdens decreased rapidly at 24-hrs post-exposure in the lung. Furthermore, inhaled MSNPs induced activation of mitogen-activated protein kinase (MAPK) signaling in the lung. In summary, single inhaled MSNPs caused mild pulmonary toxicity, which was associated with activated MAPK signaling. Taken together, our results suggest that the inhalation toxicity of MSNPs should be carefully considered at the molecular level.

Low-dose of organic trace minerals reduced fecal mineral excretion without compromising performance of laying hens

  • Qiu, Jialing;Lu, Xintao;Ma, Lianxiang;Hou, Chuanchuan;He, Junna;Liu, Bing;Yu, Dongyou;Lin, Gang;Xu, Jiming
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.4
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    • pp.588-596
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    • 2020
  • Objective: The objective of this study was to investigate the effects of low doses of organic trace minerals (iron, copper, manganese, and zinc) on productive performance, egg quality, yolk and tissue mineral retention, and fecal mineral excretion of laying hens during the late laying period. Methods: A total of 405 healthy hens (HY-Line White, 50-week-old) were randomly divided into 3 treatments, with 9 replicates per treatment and 15 birds per replicate. The dietary treatments included feeding a basal diet + inorganic trace minerals at commercial levels (CON), a basal diet + inorganic trace minerals at 1/3 commercial levels (ITM), and a basal diet + proteinated trace minerals at 1/3 commercial levels (TRT). The trial lasted for 56 days. Results: Compared to CON, ITM decreased (p<0.05) egg production, daily egg mass, albumen height, eggshell strength, yolk Fe concentration, serum alkaline phosphatase activity and total protein, and increased (p<0.05) egg loss and feed to egg ratio. Whereas with productive performance, egg quality, yolk mineral retention, and serum indices there were no differences (p>0.05) between CON and TRT. The concentrations of Fe and Mn in the tissue and tibia were changed notably in ITM relative to CON and TRT. Both ITM and TRT reduced (p<0.05) fecal mineral excretion compared to CON. Conclusion: These results indicate that dietary supplementation of low-dose organic trace minerals reduced fecal mineral excretion without negatively impacting hen performance and egg quality.

Assessment of Water and Pollutant Mass Balance by Soil Amendment on Infiltration Trench (침투도랑 토양치환의 물순환 및 비점오염물질저감 효과 평가)

  • Jeon, Minsu;Choi, Hyeseon;Kang, Heeman;Kim, Lee-hyung
    • Journal of Wetlands Research
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    • v.22 no.2
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    • pp.145-152
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    • 2020
  • Highways are characterized by high non-point pollutant emissions due to high traffic volumes and sections that cause abrupt change in driving speed (i.e. rest stations, ticketing office, etc.). Most highways in Korea were constructed with layers that do not allow adequate infiltration. Moreover, non-point pollution reduction facilities were not commonly installed on domestic highways. This study was conducted to evaluate a facility treating highway runoff and develop a cost-effective design for infiltration facilities by using soil amendment techniques. Performing soil amendment increased the hydraulic retention time (HRT) and infiltration rate in the facility by approximately 30% and 20%, respectively. The facility's efficiency of removing non-point pollutants (Total Suspend Soiled (TSS), Chemical Oxygen Demand(COD), Biological Oxygen Demand(BOD), Total Nitrogen (TN) and Total Phosphorus, (TP) were also increased by 20%. Performing soil amendment on areas with low permeability can increase the infiltration rates by improving the storage volume capacity, HRT, and infiltration area. The application of infiltration facilities on areas with low permeability should comply with the guidelines presented in the Ministry of Environment's Standards for installation of non-point pollution reduction facilities. However, soil amendment may be necessary if the soil infiltration rate is less than 13 mm/hr.

The Aeration to Improve Manganese and Chloroform of Effluent at Sludge Thickener of the Conventional Water Treatment Plant (정수장 슬러지 폭기가 방류수 망간 및 클로로포름에 미치는 영향)

  • Choi, Ilgyung;Beak, Inho;Jeong, Chanwoo;Lee, Sungjin;Park, Jungwook
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.2
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    • pp.113-118
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    • 2014
  • So many nationwide drinking water treatment plants are under much difficulties by new reinforced discharged effluent standards. Generally, the sludge at thickener should be retended for a long time during usual days. Sometime, the soluble manganese and chloroform may be formed under the anaerobic condition in the sludge thickener when the sludge retention time is longer with low turbidity. This phenomenon results in difficulties to keep regulatory level of the discharged effluent. It was necessary to improve the operation conditions and process itself in order to meet water quality standard recently reinforced. For an effort to overcome the problems, a sludge aeration was successfully implemented into the thickening process. Sludge aeration prevent particle oxidated Manganese eluting soluble de-oxidated Manganese, excrete formated Chloroform from effluent to air, and improve sludge settling through homogenized sludge particle. We aerated sludge at the conventional water treatment plant, measured Manganese and Chloroform of clarified water at upper sludge, and solid-fluid interface height of sludge in mass cylinder. As a result, contaminant's concentrations of the final effluent was much decreased : 41% of manganese, approximately 62% of chloroform and 35% of sludge volume, compared with non-aeration sludge.

Chemical Compositions Trends of Airbone PArticles at Kunsan (군산지역 부유분진의 계절적 농도변화와 화학적 조성에 대한 연구)

  • 오진만;김득수
    • Journal of Korean Society for Atmospheric Environment
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    • v.17 no.6
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    • pp.475-485
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    • 2001
  • The presence of airborne particles in the earth atmosphere expert important controls on the global climate because of their effects on the radiative balance. However, there are major uncertainties associated with the direct and indirect radiative effects of aerosols. In addition, their physicochemical properties cannot only the decline of air quality but also damage human health. Airborne particles were collected by two different commercial air samples, high volume sampler(for TSP) and low volume sampler(for P $M_{10}$ ) at the campus of Kunsan National University during February to September, 2000. In most cases, TSP and P $M_{10}$ were sampled once a week for the duration of 24 hours from 9:00 a.m. In addition samples were collected more intenisve, when the yellow dust was expected. Each sample was analyzed for pH and major ions concentration (C $l^{[-10]}$ , S $O_4$$^{2-}$, N $O_3$$^{[-10]}$ , N $a^{+}$, N $H_4$$^{+}$, $K^{+}$, $Mg^{2+}$, $Ca^{2+}$) by ion chromatography and atomic absorption spectrophotometry. Acidity (pH) of TSP and P $M_{10}$ ranged from 5.09 to 8.51 and from 6.22 to 7.54, respectively. The concentrations of airborne particles were found to satisfy both the short and long-term air quality standards during the sampling period. If the ratio of ionic concentrations originating from None sea salt(Nss) to sea salt(ss) in aerosol samples was concerned, it was found that the ionic concentrations from marine environment contributed dominantly in total mass concentration in the airborne particles. When seasonal trends were examined, the TSP concentrations in spring were higher than those of other seasons. It may result form frequent occurrences of yellow dust and during the spring season. The concentration ratio of P $M_{10}$ to TSP ranged from 0.78 to 1 during the sampling period. pH in the airborne particle was highest during spring, but the other seasons maintained almost same level. These results suggest that alkaline species in yellow dust can directly neutralize aerosol acidity. During spring season, yellow dust could be a positive factor that can defer the acidification of surface soil and water by neutralizing acidic aerosols in the atmosphere.osphere.

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Analytical Method Development and Monitoring of Residual Solvents in Dietary Supplements (건강기능식품 중 잔류용매 분석법 개발 및 모니터링)

  • Lee, Hwa-Mi;Shin, Ji-Eun;Jang, Young-Mi;Kim, Hee-Yun;Kim, Mee-Hye
    • Korean Journal of Food Science and Technology
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    • v.42 no.4
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    • pp.390-397
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    • 2010
  • Residual solvents in foods are defined as organic volatile chemicals used or produced in manufacturing of extracts or additives, or functional foods. The solvents are not completely eliminated by practical manufacturing techniques and they also may become contaminated by solvents from packing, transportation or storage in warehouses. Because residual solvents have no nutritional value but may be hazardous to human health, there is a need to remove them from the final products or reduce their amounts to below acceptable levels. The purpose of this study was to develop and evaluate an analytical method for the screening of residual solvents in health functional foods. Furthermore, the aim of this study was to constitute a reasonable management system based on the current state of the market and case studies of foreign countries. Eleven volatile solvents such as MeOH, EtOH, trichloroethylene and hexane were separated depending on their column properties, temp. and time using Gas Chromatography (GC). After determining the GC conditions, a sample preparation method using HSS (Head Space Sampling) was developed. From the results, a method for analyzing residual solvents in health functional foods was developed considering matrix effect and interference from the sample obtained from the solution of solvents-free health functional foods spiked with 11 standards solutions. Validation test using the developed GC/HSS/MS (Mass Spectrometry) method was followed by tests for precision, accuracy, recovery, linearity and adequate sensitivity. Finally, examination of 104 samples grouped in suits was performed by the developed HSS/GC/MS for screening the solvents. The 11 solvents were isolated from health functional foods based on vapor pressure difference, and followed by separation within 15 minutes in a single run. The limt of detection (LOD), limit of quantification (LOQ), recovery and coefficient of variation (C.V.) of these compounds determined by the HSS/GC/MS were found to be 0.1 pg/mL, 0.1-125 pg/g, 51.0-104.6%, and less than 15%, respectively. Using the developed HSS/GC/MS method, residual solvent from 16 out of 104 health functional products were detected as a EtOH. This method therefore seems t o be a valuable extension ofanalytical method for the identification of residual solvents in health functional food.

Characteristics of stormwater runoff from urbanized areas (도시화된 토지이용에서 유출되는 강우유출수의 유출특성분석)

  • Mercado, Jean Margaret R.;Geronimo, Franz Kevin F.;Choi, Jiyeon;Song, Young-Sun;Kim, Lee-Hyung
    • Journal of Wetlands Research
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    • v.14 no.2
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    • pp.159-168
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    • 2012
  • Stormwater runoff affects the quality of surface water and groundwater due to the nonpoint sources (NPSs) of pollutants that it carries during storm events. Typically, urbanized areas experience high pollutant mass emission because of paved roads and other areas which are all highly impervious. For this reason, proper identification of the levels of pollutants from the watershed area is important to pass the Ministry of Environment of the Republic of Korea's water quality standards in rivers and streams. This research was conducted in order to determine and quantify the different constituents present in stormwater runoff generated from highly impervious areas in Cheonan City, Korea. Also, the average event mean concentration (EMC) of stormwater runoff from paved areas was compared with EMCs of other countries to determine the possible causes of its occurrence. In addition, the occurrence of first flush phenomenon was studied in order to find the first flush criteria to be used on the design of best management practices. The results show the pollutant concentration of stormwater runoff was higher than other countries due its landuse and relatively small size of catchment area. During the first 30 minutes of the rainfall events, occurrence of first flush phenomenon was highly evident. Several factors affected the pollutant concentrations in the stormwater such as landuse type, geographic and topographic characteristics,catchment area and amount of rainfall. This research can provide guidance in achieving an effective NPS pollution management applicable to highly urbanized areas in the future.

Rapid Analytical Method of Volatile- and Semivolatile Organic Compounds in Water and their Monitoring in Water Treatment Plants (물 시료 중 휘발성 및 반휘발성 유기물질들의 빠른 분석법 및 정수처리 단계별 모니터링)

  • Shin, Ho-Sang;Ahn, Hye-Sil
    • Analytical Science and Technology
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    • v.17 no.3
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    • pp.240-250
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    • 2004
  • A gas chromatography-mass spectrometric (GC-MS) assay method was developed for the rapid and sensitive determination of volatile- and semivolatile organic compounds in water. Two hundreds mL of water sample was extracted in a 250 mL separatory funnel with 1 ml of pentane at pH 6.5. Fluorobenzene and 1,2-dichlorobenzene-d4 as internal standards were added to water sample and the solution was mechanically shaken for 5 min and analyzed by GC-MS (selected ion monitoring) without more any concentration or purification steps. The peaks had good chromatographic properties and the extraction of these compounds from water also gave relatively high recoveries with small variations. The range of detection limits of the assay was 0.5-10 ng/L. Turnaround time for up to about 40 samples was one day. This method is simple, convenient, and can be learned easily by relatively inexperienced personnel. This method was used to analyze 15 volatile- and semivolatile organic compounds in water of a Lake, and raw and treated water from three Water Treatment Plants in Korea. As the analytical results, benzene, toluene, xylene, isopropylbenzene, 1,3,5-trimethylbenzene, 1,2,4-trimethylbenzene, naphthalene and 2,4,6-trichlorophenol were detected at concentrations of up to 0.4, 1.9, 1.3, 0.2, 1.8, 13.0, 1.7 and $1.1{\mu}g/L$, respectively. But chlorobenzene, trichloroethylene, tetrachloroethylene, ethylbenzene, n-butylbenzene and dibromochloropropane levels during that period were not significant. The removal effect of the compounds in three Water Treatment Plants was calculated. The compounds studied were generally removed during conventional water treatment, especially during the active carbon filtration.

A Study on People's Coverage on People Pages: Focusing on the Main Reports in Four National Dailies (한국 신문의 사람면에 대한 보도형태와 특성 연구: 4대 중앙일간지 사람면 박스기사에 실린 대표인물을 중심으로)

  • Im, Yang-June
    • Korean journal of communication and information
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    • v.40
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    • pp.249-286
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    • 2007
  • This study examines the main characteristics and differences on people's page in selected four national dailies, such as Chosun Ilbo, Joongang Ilbo, Seoul Shinmum and Hankyoreh Shinmun. Both Chosun Ilbo and Joongang Ilbo are categorized as the conservatives; while Seoul Shinmum and Hankyoreh Shinmun as the progressive. This study has been done by applying methods of content analysis to reveal the differences in terms of people's occupations, types of reports, their philosophies, and standards of selecting people by the dailies for the people's pages. The results shows that the conservative newspapers are very similar to the progressive newspapers in terms of occupations and the types of reports, covering the people on people's pages. More specifically, both the conservative dailies and the progressive dailies report the people for whose jobs are related to both social and cultural works. However, the conservative newspapers have much more coverages than the progressive papers in terms of the publicity reporting on the people. The conservatives are also much more reports on the people who are eager to economic success than the progressive dailies; while the progressives papers have much coverages on those who are interesting in helping others than the conservatives papers. Finally, this study reveals that the conservative dailies mainly cover those who are in publicity activities and social elite groups, while the progressive newspapers are the social celebrities and persons of fame in society.

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