• Title/Summary/Keyword: Harmful Effects

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Evaluation of Bottom Ash on the Application for the Aggregate of Concrete (콘크리트용 골재로서의 Bottom Ash 활용성 평가)

  • Kim, Sang-Chel
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.5 no.2
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    • pp.105-115
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    • 2010
  • In this study, as one of solutions associated with the shortage of treatment area of industrial waste and the containment of its harmful components, the bottom ash which is known to be by-products of thermoelectric power plant was selected and its applicability for aggregate of concrete mixture was measured. Hardness test, sieve analysis, water-absorption test and SEM analysis were carried out to investigate the possibility of using bottom ash as a replacement of coarse and fine aggregate. Chemical analyses such as ignition loss test and X-ray incidence were carried out also. In addition, values for slump, strength, permeability, freeze and thaw, and carbonation were evaluated in terms of effects of replacement ratio of bottom ash. As the results, it was found that, though bottom ash is in short supply of fine particles and is in lack of cohesion, these problems can be solved by partially mixing with natural aggregates or improving in a process of production. In addition, bottom ash has not only advantage of durability but also acquirement of general compressive strengths in case that a certain proportion of natural aggregate is applied to mixture, in spite that unit water or chemical admixture should be increased to acquire good workability due to plenty of porosity.

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The Effect of Alcohol-related Harm Preventing Intervention on Drinking Frequency and Problem Behaviors of Adolescent: A Meta-analysis (청소년의 음주폐해 예방 중재가 음주 빈도와 문제행동에 미치는 효과: 메타분석)

  • Song, A-Young;Song, Ye-Won;Lee, Jae-Shin
    • The Journal of the Korea Contents Association
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    • v.17 no.2
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    • pp.687-695
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    • 2017
  • This study tried to confirm the effective intervention to reduce drinking frequency and problem behaviors among the three interventions; school based, feedback, and behavior change. Meta-analysis was conducted targeting at 16 studies of randomized controlled trial in which alcohol intervention has been applied to adolescent. The drinking frequency and problem behaviors were analyzed by follow up period. There was a significant difference in the feedback intervention to reduce the frequency of drinking under 3 months of follow up period. Also, there was a significant difference in the feedback intervention to reduce the problematic behaviors of drinking between 4 and 12 months of follow up period(p<.05). The study confirmed that feedback intervention is effective in reducing the frequency of drinking during the follow up period under 3 months, and it is effective in reducing the problem behaviors of drinking during the 4~12 months of follow up period. Also, the study confirmed that school-based intervention and feedback intervention were useful in reducing and preventing harmful effects of drinking by adolescents.

Gas Migration in Low- and Intermediate-Level Waste (LILW) Disposal Facility in Korea (중·저준위 방사성폐기물 처분시설 폐쇄후 기체이동)

  • Ha, Jaechul;Lee, Jeong-Hwan;Jung, Haeryong;Kim, Juyub;Kim, Juyoul
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.12 no.4
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    • pp.267-274
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    • 2014
  • The first Low- and Intermediate-Level Waste (LILW) disposal facility with 6 silos has been constructed in granite host rock saturated with groundwater in Korea. A two-dimensional numerical modeling on gas migration was carried out using TOUGH2 with EOS5 module in the disposal facility. Laboratory-scale experiments were also performed to measure the important properties of silo concrete related with gas migration. The gas entry pressure and relative gas permeability of the concrete was determined to be $0.97{\pm}0.15bar$ and $2.44{\times}10^{-17}m^2$, respectively. The results of the numerical modeling showed that hydrogen gas generated from radioactive wastes was dissolved in groundwater and migrated to biosphere as an aqueous phase. Only a small portion of hydrogen appeared as a gas phase after 1,000 years of gas generation. The results strongly suggested that hydrogen gas does not accumulate inside the disposal facility as a gas phase. Therefore, it is expected that there would be no harmful effects on the integrity of the silo concrete due to gas generation.

Recent Trends of Vessel-Source Pollution (선박 기인 오염물의 처리동향 및 대책)

  • Park, Sang-Ho;Kim, In-Soo
    • Proceedings of KOSOMES biannual meeting
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    • 2006.11a
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    • pp.97-104
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    • 2006
  • Though stringent guidelines are in place to protect the harbor environment, pollution from ships, from the ports terminals. Discharge from the ballast tanks of ships, though illegal, does occur. Such vessels, arriving from distant ports of call, can introduce exotic species of plants and animals, causing disruption of the local food web. Discharges rich in nitrogen can generate the rapid growth of plankton, eventually leading to a condition known as red tide that is lethal to some coastal organisms. In addition to the harbor's negative effects on marine organisms, the diesel engines of the ships and the trucks that haul cargo to and from the ports release large volumes of diesel exhaust into the atmosphere. IMO(International Maritime Organization) is strongly proceeding with adoption of a new maritime environment convention and coming into effect for regulation enhancement about the pollutants which are happened in a ship recently. Study about the conventions that our country currently comes into effect, and there is during forwarding and correspondence must be performed effectively. In this paper, International convention on the control of harmful Anti-Fouling system on ship, Ballast water management, Prevention of air pollution from ships, treat a main pending problem in ocean related environmental regulation convention.

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Domestic Restrictions on the Opening of Retail Stores

  • Yoon, Myoung-kil;Kim, Yoo-oh;Lee, Min-kweon;Nam, Kung-sok
    • Journal of Distribution Science
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    • v.4 no.1
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    • pp.121-140
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    • 2006
  • This study has explored a number of problems arising from distribution restrictions and the ways to improve efficiency. As matters stand, since the cooperation between larger stores and local retailers is limited due to the nature of the market, the current situations call for bottom up restrictions such as the active promotion of smaller merchants and traditional marketplaces, the enhancement of the competitiveness of smaller merchants and manufacturers through the establishment of a customized consulting support program for individual shops, and the continual support for traditional marketplaces with facilities and management modernization. The government should maintain the optimal balance between the efficiency and effectiveness of the distribution industry through such bottom up restrictions as shown above, rather than the top down restrictions primarily relying on the hurdles to the establishment of stores. The problems raised in this study include: (i) the decline of traditional marketplaces and the alleged over saturation of stores; (ii) the possible abuse of indiscreet restrictive measures; (iii) the harmful effects of the monopoly or oligopoly by larger distributors; and (iv) the lack of systematic programs to promote development. The ways to improve efficiency are: (i) the establishment of the policies to specialize and nurture traditional marketplaces; (ii) the effort to prevent the injury arising from monopoly; (iii) the two tire strategies for the coexistence of larger and smaller businesses; and (iv) the administration of joint sales promotion and training.

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The Effect of Pulsatile Versus Nonpulsatile Blood Flow on Viscoelasticity and Red Blood Cell Aggregation in Extracorporeal Circulation

  • Ahn, Chi Bum;Kang, Yang Jun;Kim, Myoung Gon;Yang, Sung;Lim, Choon Hak;Son, Ho Sung;Kim, Ji Sung;Lee, So Young;Son, Kuk Hui;Sun, Kyung
    • Journal of Chest Surgery
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    • v.49 no.3
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    • pp.145-150
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    • 2016
  • Background: Extracorporeal circulation (ECC) can induce alterations in blood viscoelasticity and cause red blood cell (RBC) aggregation. In this study, the authors evaluated the effects of pump flow pulsatility on blood viscoelasticity and RBC aggregation. Methods: Mongrel dogs were randomly assigned to two groups: a nonpulsatile pump group (n=6) or a pulsatile pump group (n=6). After ECC was started at a pump flow rate of 80 mL/kg/min, cardiac fibrillation was induced. Blood sampling was performed before and at 1, 2, and 3 hours after ECC commencement. To eliminate bias induced by hematocrit and plasma, all blood samples were adjusted to a hematocrit of 45% using baseline plasma. Blood viscoelasticity, plasma viscosity, hematocrit, arterial blood gas analysis, central venous $O_2$ saturation, and lactate were measured. Results: The blood viscosity and aggregation index decreased abruptly 1 hour after ECC and then remained low during ECC in both groups, but blood elasticity did not change during ECC. Blood viscosity, blood elasticity, plasma viscosity, and the aggregation index were not significantly different in the groups at any time. Hematocrit decreased abruptly 1 hour after ECC in both groups due to dilution by the priming solution used. Conclusion: After ECC, blood viscoelasticity and RBC aggregation were not different in the pulsatile and nonpulsatile groups in the adult dog model. Furthermore, pulsatile flow did not have a more harmful effect on blood viscoelasticity or RBC aggregation than nonpulsatile flow.

Changes of the Structural and Biomechanical Properties of the Bovine Pericardium after the Removal of ${\alpha}$-Gal Epitopes by Decellularization and ${\alpha}$-Galactosidase Treatment

  • Nam, Jinhae;Choi, Sun-Young;Sung, Si-Chan;Lim, Hong-Gook;Park, Seong-Sik;Kim, Soo-Hwan;Kim, Yong Jin
    • Journal of Chest Surgery
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    • v.45 no.6
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    • pp.380-389
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    • 2012
  • Background: Bovine pericardium is one of the most widely used materials in bioprosthetic heart valves. Immunologic responses have been implicated as potential causes of limited durability of xenogenic valves. This study aimed to determine the effectiveness of decellularization and ${\alpha}$-galactosidase (${\alpha}$-gal) to remove major xenoreactive antigens from xenogenic tissues. Materials and Methods: Recombinant Bacteroides thetaiotaomicron (B. thetaiotaomicron) ${\alpha}$-gal or decellularization, or both were used to remove ${\alpha}$-gal from bovine pericardium. It was confirmed by ${\alpha}$-gal-bovine serum albumin-based enzyme-linked immunosorbent assay (ELISA), high-performance anion exchange chromatography, flow cytometry, 3,3'-diaminobenzidine-staining, and lectin-based ELISA. The mechanical properties of bovine pericardium after decellularization or ${\alpha}$-gal treatment were investigated by tests of tensile-strength, permeability, and compliance. Collagen fiber rearrangement was also evaluated by a 20,000${\times}$ transmission electron microscope (TEM). Results: Recombinant B. thetaiotaomicron ${\alpha}$-gal could effectively remove ${\alpha}$-gal from bovine pericardium B. thetaiotaomicron (0.1 U/mL, pH 7.2) while recombinant human ${\alpha}$-gal removed it recombinant human ${\alpha}$-gal (10 U/mL, pH 5.0). There was no difference in the mechanical properties of fresh and recombinant ${\alpha}$-gal-treated bovine pericardium. Furthermore, the TEM findings demonstrated that recombinant ${\alpha}$-gal made no difference in the arrangement of collagen fiber bundles with decellularization. Conclusion: Recombinant B. thetaiotaomicron ${\alpha}$-gal effectively removed ${\alpha}$-gal from bovine pericardium with a small amount under physiological conditions compared to human recombinant ${\alpha}$-gal, which may alleviate the harmful xenoreactive immunologic responses of ${\alpha}$-gal. Recombinant ${\alpha}$-gal treatment had no adverse effects on the mechanical properties of bovine pericardium.

A Study on the Reduction of Harmful Compound in Cigarette Smoke [Part II] -Influence of solvont extraction- (담배 연기중(煙氣中)의 유해물감소(有害物減少)에 관한 연구(硏究)[제이보(第二報)] -용매추출(溶妹抽出)의 영향(影響)-)

  • Park, Taek-Kyu;Kim, Ki-Hwan
    • Applied Biological Chemistry
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    • v.22 no.1
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    • pp.58-63
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    • 1979
  • The solvent extracting of the tobacco has been carried out in order to find out any effects for the removal and/or reduction of nicotine from tobacco without affecting the tobacco flavor. We have now completed the physico-chemical characterization of the solvent untreated/treated tobaccos and 2) the contents of the tar and nicotine in the smoke. The results obtained ate like followings; 1. 3% alcohol extraction reduced the total nitrogen content for the Bright by 36.4%. However, it could not reduce the sugar content. 2. Nicotine content in tobacco leaves was inversely proportional to the dipping time Essentially same results were obtained in anacidic solution and even in a solution containing both alkali and acid. 3. Derivative thermogravimetric(DTG) curves indicated test extraction was effective by removing tobacco leaf components which could decompose or volatilize between the temperature of $150^{\circ}C\;and\;350^{\circ}C$. 4. 3% alcohol extracted leaf have the substantial improvements as following; (1) bulk filling power of 10% and 24% for Burley and Bright tobacco, respectively, (2) combustibility shortening of about 3 minute and 2 minute for Burley and Bright tobaccos, respectively, (3) reduction ratio(%) of nicotine was found to be shout 61.5% and 54.5% for Burley and Bright tobacco, respectively, (4) reduction ratio (%) of tar was obtained to he about 25% and 15% for Burley and Bright tobacco, respectively.

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Selection of Kimchi Starters Based on the Microbial Composition of Kimchi and Their Effects (김치 미생물 조성을 바탕으로 한 김치 스타터의 선정 및 효과)

  • Jin, Hyo-Sang;Kim, Jong-Bum;Yun, Yeong-Ju;Lee, Kyung-Ja
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.5
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    • pp.671-675
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    • 2008
  • Based on information about the major microbial composition of kimchi and its relation to the taste, Leuconostoc mesenteroides K2M5 and Lactobacillus sakei K5M3 were selected as kimchi starter candidates. These two strains were found to be safe for industrial use because they showed neither harmful characteristics like ${\beta}$-hemolysis, ammonia and indole formation, and gelatin liquefaction, nor enzymatic activities like phenylalanine deaminase, ${\beta}$-glucuronidase, ${\beta}$-glucosidase, 7${\alpha}$-dehydroxylase and nitroreductase. Starter kimchi made with these strains were better in taste than the conventional kimchi when they are evaluated both by laboratory personnel and the public. Also microbial analysis of starter kimchi showed only starter bacteria after they were fermented to have the optimum acidity. Starter kimchi prepared with these two strains were not much different in physicochemical properties to the conventional kimchi except in that the starter kimchi were much higher in volatile organic acid content such as lactic acid. These results suggest that kimchi quality can be controlled to have consistent properties, both in taste and microbial composition, by using bacterial starters.

Post Discharge Nursing Needs of Patients with Open Heart Surgery (개심술 환자의 퇴원후 간호요구에 대한 조사연구)

  • 김명희
    • Journal of Korean Academy of Nursing
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    • v.23 no.4
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    • pp.664-677
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    • 1993
  • The purpose of this study was to provide basic data for the development of educational material in Korean for patient3 being discharge after open heart surgery. The subjects were 45 adult patients who were seen in the out -patient department of the thoracic surgery unit of P University hospital between February 1993 and May 1993. The data were collected through a chart review and interview. Nursing needs, and the patients status related to diet, activity, medication, physical and psychoemotional limitations were analyzed. The results are summarized as follows ; 1. Mitral valve replacement was the most frequent type of surgery(91.2%). In most cases, a mechanical valve was used (91.0%) . The duration of admission after the operation was two to four weeks for most of the patients(48.9%). The follow-up period was between one and two years for 28.9% of the patients and below 6 years for all of the patients. 2. Many Patients didn’t know the importance of a low salt diet(57.8%), and did not get any education on low salt diet (66.7%). Gimchi was included as one of the most commonly ingested foods (77.8%). All of the patients indicated nursing needs related to education about low salt diets and further they indicated a major interest in foods that are harmful (57.7%) or foods that are safe(51.1% ). 3. Most patients did not recognize the need for limitations on physical activity(84.4%). Further, 31.1% of them could not return to work at the time of the study. All patients had nursing needs related to physical activity, with the most frequent questions being about the permissble degree of activity and special cautions dictated by their illness (60.0%). 4. Many patients were ignorant of the necessity of medication(55.6%) . Forty percent of the patients were taking additional drugs, usually herb drugs. The time and duration of medication and the side effects of drugs were common concerns (57.7%) related to nursing. needs about medication and were mentioned by all of the patients. 5. All of the patients complained of physical discomfort including the following : memory disturbance(62.2%), weight gain(60.0%), chest tightness (55.6%), hair loss(51.1%), sleep disturbance(46.7%) and other symptoms in that order of frequency. Nursing needs related to physical condition were a concern for all of them. The viability and function of the replaced valve(53.3%) and weight gain(60.0%) were mal or concerns. 6. Looking at their psychoemotional condition it was found that 36 patients(80.0%) were emotionally unstable. The causes were physical discomfort(17 patients), insufficient knowlege of open heart surgery(6 patients), fear of death(6 patients), familial over protection(2 patients ) and lack of support (5 patients).

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