• Title/Summary/Keyword: Heavy Use

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The efficacy of denture cleansing agents: A scanning electron microscopic study (수종 의치세정제의 세척 효과에 관한 주사전자현미경적 비교 연구)

  • Yun, Bo-Hyeok;Yun, Mi-Jung;Hur, Jung-Bo;Jeon, Young-Chan;Jeong, Chang-Mo
    • The Journal of Korean Academy of Prosthodontics
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    • v.49 no.1
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    • pp.57-64
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    • 2011
  • Purpose: The purpose of this study was to compare the cleansing performance of a distilled water, a diluted solution of sodium hypochlorite as a household bleaching cleanser and three alkaline peroxide cleansers in vivo plaque deposits by using scanning electron microscope. Materials and methods: Five individuals were selected from department of the prosthodontics in Pusan National University Hospital, and each of them was inserted with specimens for plaque accumulation in their temporary dentures for 48 hours. The specimens were removed and cleaned by each cleansing agents for 8 hours. Scanning electron micrographs were made from the specimens at a magnification of ${\times}2,000$. A panel of ten persons with a dental or paradental background, but not directly involved in the study, was selected to analyze the photomicrographs to determine which denture cleanser was more effective in removing plaque. Results: Diluted solution of sodium hypochlorite was the most effective at removing plaque following $Polident^{(R)}$, $Cleadent^{(R)}e$, $Bonyplus^{(R)}$ and distilled water in order. But there was no significant difference of cleansing efficacy between diluted solution of sodium hypochlorite and $Polident^{(R)}$, $Polident^{(R)}$ and $Cleadent^{(R)}e$, $Cleadent^{(R)}e$ and $Bonyplus^{(R)}$, respectively (P > .05). Alkaline peroxide cleansers by themselves cannot adequately remove accumulated plaque deposits, especially if the deposits are heavy. Corrosion could be seen on the surface of non-precious alloy specimens immersed in diluted solution of sodium hypochlorite. Conclusion: It is recommended to use of alkaline peroxide type cleansers with brushing whenever possible, since denture cleanliness is often poor due to the relative inefficiency of these cleansers.

Cardiac Intracoronary Stenting vs CABG: Prevention of Medical Accident (심장 스텐트 시술과 의료사고 예방)

  • Kim, Kyoung Reay;Park, Kook Yang
    • The Korean Society of Law and Medicine
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    • v.18 no.2
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    • pp.163-194
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    • 2017
  • Coronary artery disease has increased in Korea as the country enters the aged society. It is well known that the incidence of coronary artery disease is related to aging, hypertension, diabetes, hyperlipidemia, and dietary habit. For effective treatment of significant coronary stenosis, close coordination between cardiac surgery and cardiology team is essential. Especially cardiologists' decision whether to do the stent placement or CABG is very important because the cardiologists usually start to consult the patients for their treatment. Recently, non-surgical interventions(that is stent placement) in cardiology field have dramatically increased as the national insurance system removed the limitation of the number of stents deployed. However, accidents are often caused by inappropriate use of stents, especially in patients with triple coronary disease or left main disease with heavy coronary calcifications. Another aspect of stent placement is to cope with an emergency case in the event of coronary rupture or pericardial tamponade during coronary interventions without cardiac surgeons. In the past two years, the Korea Consumer Agency (Consumer Dispute Coordination Committee) analyzed eight cases of medical dispute settlement. Only two hospitals were manned with both cardiologists and cardiac surgeons. Seven patients died of procedures of stenting and five patients died on the day of the procedure. Among the 8 cases, 5 cases showed 3 vessel disease and the rest of the cases had either severe calcification, complete occlusion or poor coronary antomies for stenting According to a 2017 national data registry of coronary stenting, less than 3 drug-eluting stents were implanted in 98% of all patients. In 2015, the number of stent procedures was 38,922, and approximately in 800 (2%) cases, more than four stents were used per patient. We emphasize that it is necessary to seriously consider the cost-benefit analysis between stent and CABG. The patient has the right to choose the right procedure by asking the liability of 'instruction explanation obligation'. He should be well informed of the pros and cons of both procedures to avoid overuse of stent. It can be solved by intimate discussion of individual cases with the cardiac surgeon and the patient. Unilateral dialogue with the patient, forceful restriction on the number of stenting, lack of surgeon's backup in difficult cases should all be avoided. It is also necessary to solve the problem not only at the hospital level, such as multidisciplinary integrated medical care, but also a nationwide solution such as expanding cardiac surgeons as essential personnel to public officials.

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Tracheal Reconstruction with Perichondrial Graft - An Experimental Study in Rabbits - (연골피막편 이식후 기관 결손부위의 재생에 관한 실험적 연구(제 1 보))

  • 이원상;서장수;이성은;홍원표;박찬일
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1982.05a
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    • pp.10.3-11
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    • 1982
  • Recently through the advancement of medical and surgical managements and the development of low pressure cuffed endotracheal tube, incidence of tracheal stenosis was decreased significantly. Though its incidence was decreased markedly, stenosis was developted unfortunately in the situations such as long term use of respirator, heavy infection, trauma of the trachea and long term intubation etc. Tracheal stenosis had been handled with various methods such as mechanical dilatation, tissue graft techniques, luminal augumentation and end to end anastomosis due to their individual advantages but their effects were not satisfactory. In 1959 Lester had been found the regenerated cartilage from the perichondrium of the rib incidentaly. Since then Skoog, Sohn and Ohlsen were reported chondrogenic potential of perichondrium through the animal experiments. Though many different materials have been tried to rebuild stenosis and gaping defect of trachea, tracheal reconstruction has been a perplexing clinical problems. We choose the perichondrium as the graft material because cartilage is the normal supporting matrix of that structure and it will be an obvious advantage to be able to position perichondrium over a defect and obtain new cartilage there. The young rabbits, which were selected as our experimental animals, were sacrified from two to eight weeks after surgery. The results of our experiment were as follows; 1) In control group, the defect site of trachea was covered with fibrosis and vessels but graft site was covered with hypertrophied perichondrium and vessels. 2) Respiratory mucosa was completely regenerated in defect sites both control and grafted groups. 3) The histologic changes of the grafted sites were as follows: 2 weeks- microvessel dilatation, inflammatory reaction, initiation of fibrosis 4 weeks- decreased microvessel engorgement, submucosal fibrosis, decreased inflammatory reaction immatured cartilage island was noted in the grafted perichondrium (one specimen) 6 weeks- mild degree vascular engorgement submucosal fibrosis. chronic inflamatory reaction cartilage island and endochondrial ossification was noted in the grafted perichondrium (Two specimens) 8 weeks- minute vascular engorgement dense submucosal fibrosis. loss of inflammatory reaction. cartilage island was noted in the grafted perichondrium (two specimens) 4) There was no significant differences in regeneration between active surface in and out groups. 5) We observed immatured cartilage islands and endochondrial ossification in the perichondrial grafted groups where as such findings were not noted in control groups except fibrosis. We concluded that perichondrium was the adequate material for the reconstruction of defected trachea but our results was not sufficient in the aspect of chondrogenic potential of perichondrium. So further research has indicated possibility of chondrogenic potential of perichondrium.

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Clinical Characteristics of Miliary Tuberculosis (속립성 폐결핵의 임상적 특성)

  • Kim, Jin-Ho;Moon, Doo-Seop;Lee, Dong-Suck;Park, Ik-Soo;Yoon, Ho-Joo;Shin, Dong-Ho;Kim, Tae-Wha;Park, Sung-Soo;Lee, Jung-Hee
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.2
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    • pp.144-151
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    • 1994
  • Background: Miliary tuberculosis almost always results from the discharge of infected caseous material into the blood stream, usually from a well hidden lymph node in the presentation of this disease in the past four decades, and although it is seen less frequent1y today than previously, its presentation and manifestation may require greater suspicion and diligence by the physician. We investigated the clinical characteristics, predisposing factors and accompanying diseases of miliary tuberculosis and tried to acquire the early diagnosis and treatment of this disease. Methods: A retrospective clinical study was done on 40 cases of miliary tuberculosis admitted to Hanyang University Hospital from Mar. 1989 to Dec.1992. The study investigated age and sex distribution, seasonal distribution, duration of symptoms before admission, pre-disposing factors, clinical symptoms, biochemical findings, chest X-ray findings, extrapulmonary tuberculosis associated with miliary tuberculosis, prognosis and mortality rate. Results: 1) The patients were most common in the age group between 20 and 29(23%) and the ratio of male to female was 1.4:1(male 23 : female 17). 2) Sputum smears for tubercle bacilli were positive in 5 cases(13%). 3) The most common clinical symptoms were fever with chilling(47.5%), coughing(47.5%), second most common symptom was dyspnea(32.5%), and the physical findings on admission were tachycardia(30%), weight loss(27.5%), meningeal signs(17.5%) in order. 4) The predisposing factors were heavy alcohol drinking(6 cases), steroid use(3 cases), pregnancy(2 cases) etc. 5) The chest X-ray findings on admission were miliary shadow only(40%), in addition pneumonic infiltration, pleurisy, and calcification in order. 6) The extrapulmonary tuberculosis associated with miliary tuberculosis were tuberculous meningitis(30%), bone and joint tuberculosis(17.5%), intestinal tuberculosis(15%) in order. 7) Biochemical findings were increased SGOT/SGPT(32.5%), increased alkaline phosphatase(32.5%), hypoalbuminemia(15%), hyponatremia(15%) etc. 8) About 4-6 weeks later after treatment(INH, RFP, PZA, EMB), 26 cases(65%) were improved on clinical symptoms or chest X-ray, 12 cases(30%) were stationary or aggravated, and 2 cases(5%) were died. Conclusion: For the early diagnosis and treatment of miliary tuberculosis, we must see its presentation and manifestation with greater interest and suspicion and investigate its predisposing factors and accompanying diseases.

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A Survey on the Knowledge and Attitude of Workers Concerning Occupational Health (근로자의 산업보건 지식과 태도에 관한 조사연구)

  • 박영식;조수열;남철현
    • Journal of Environmental Health Sciences
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    • v.18 no.2
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    • pp.3-18
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    • 1992
  • This research was carried out on 1,017 production workers for four months from May to August, 1991, to search more effective management method of their health by grasping their knowledge and attitude on industrial health. The results of this study can be summarized as follows: 1. As for general characteristics, 74.2% were male and 25.8% were female among the 1,017 workers. The two largest age groups were 30~39, 38.7%. As for education level, graduation from high school was 58.6%, 61.2% were married, 35.9% owned their house, and workers who worked more than 1 year less than 5 years was 52.9%, workers who worked 8 hours a day was 46.7%, the largest group income level was 60~69 thousand won 21.2%, and the degree of satisfaction with work was ordinary, 45.6%. 2. The degree of recognition concerning occupational diseases was 92.5% at a very high rate. Causes of occupational diseases under the present work field were in order of noise, dust, heavy metal. The largest group of the counterplan for prevention was an improvement of working environment, 62.0%. 3. The major cause that threatens worker's health was poor working environment, 31.4%. As the best method for workers' health management, working environment management was pointed. 4. As for health examination result, the response that it is of use to health management was 53.8%. As for examination method and result, 42.7% responded that they are formal. The practice period was more than once every six months as the largest group, and the highest desire for improvement was that they wants an exact information of the result. 5. 49.3% of the respondents know about the measurement of working environment an the response that the measurement is necessary to improve working environment was 57.9%, and that the results from the measurement were reflected on improvement an management 57.5%. Appropriate period to take a measurement was more than once per six months, 40.2% and per three months, 29.1%. 6. As for safety and halth instruction, 34.5% were educated for both, 38.2% for only safety education and just 4.6% for only health education. 51.9% responded that they had never been educated out of work place. The period of its practice was more than once a month, 39.5% and every three months, 21.3%. 7. The importance of safety and health showed that the one is equal to the other, 59.8%, that the one is more important, 29.6%, and that other is more important, 7.6%. 67.7% said the necessity of a safety and health manager. 8. In spite of more or less health obstacle of work environment, 14.9% of the respondents wanted to overwork to gain an allowance for over-time work, 39.9% didn't, and 40.2% according to condition and state. 9. As the most important cause of industrial accident, 40.2% indicated unsafe behavior. As for the individual protective instrument, 66.1% of all the respondents said they have worn it to protect industrial diseases. 10. As for the degree of understanding of the contents in Industrial Safety and Health Law and Industrial Law of Accident Insurance, an affirmative response was respectively 49.3% and 50.8% and the sources of safety-health information were televisions and radios, 28.0%. Therefore, it is necessary that we do positive working environmental improvement, continuous management and health education's inforcement to increase their health and prevent occupational diseases.

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A Case Study for the Determination of Time Distribution of Frequency Based Rainfall (확률강우의 적정시간분포 결정에 관한 연구)

  • Lee, Jeong Ki;Kim, Hung Soo;Kang, In Joo
    • Journal of Wetlands Research
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    • v.6 no.3
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    • pp.71-81
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    • 2004
  • In recent, the heavy rainfall is frequently occurred and the damage tends to be increased. So, more careful hydrologic analysis is required for the designs of the hydraulic or disaster prevention structures. The time distribution of a rainfall is one of the important factors for the estimation of peak flow in hydrologic and hydraulic designs. This study is to suggest a methodology for the estimation of a rainfall time distribution which can reflect the meteorologic and topographical characteristics of Daejeon area. We collect the 34 years' rainfall data recorded in the range of 1969 to 2002 for Daejeon area and we performed the rainfall analysis with the data in between May and October of each year. According to the Huff method, the collected data corresponds to the first quartile which the rainfall is concentrated in the primary stage but the suggested method shows the different rainfall distribution with the Huff method in time. The reason is that the Huff method determines the quartile in each storm event while the suggested one determines it by estimating the dimensionless distribution of rainfall in duration after the accumulation of rainfall in time. The rainfall distributions estimated by two methodologies were applied to the Gabcheon basin in Daejeon area for the estimation of flood flow. Here we use the SCS method for the effective rainfall and unit hydrograph for the flood discharge. As the results, the peak flow for 24-hour of 100-year frequency was estimated as a $3421.20m^3/sec$ by the Huff method and $3493.38m^3/sec$ by the suggested one. We can see the difference of $72.18m^3/sec$ in between two methods and thus we may carefully determine the rainfall time distribution and compute the effective rainfall for the estimation of the peak flow.

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Agroclimatic Zone and Characters of the Area Subject to Climatic Disaster in Korea (농업 기후 지대 구분과 기상 재해 특성)

  • 최돈향;윤성호
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.s02
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    • pp.13-33
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    • 1989
  • Agroclimate should be analyzed and evaluated accurately to make better use of available chimatic resources for the establishment of optimum cropping systems. Introducing of appropriate cultivars and their cultivation techniques into classified agroclimatic zone could contribute to the stability and costs of crop production. To classify the agroclimatic zones, such climatic factors as temperature, precipitation, sunshine, humidity and wind were considered as major influencing factors on the crop growth and yield. For the classification of rice agroclimatic zones, precipitation and drought index during transplanting time, the first occurrence of effective growth temperature (above 15$^{\circ}C$) and its duration, the probability of low temperature occurrence, variation in temperature and sunshine hours, and climatic productivity index were used in the analysis. The agroclimatic zones for rice crop were classified into 19 zones as follows; (1) Taebaek Alpine Zone, (2) Taebaek Semi-Alpine Zone, (3) Sobaek Mountainous Zone, (4) Noryeong Sobaek Mountainous Zone, (5) Yeongnam Inland Mountainous Zone, (6) Northern Central Inland Zone, (7) Central Inland Zone, (8) Western Soebaek Inland Zone, (9) Noryeong Eastern and Western Inland Zone, (10) Honam Inland Zone, (ll) Yeongnam Basin Zone, (12) Yeongnam Inland Zone, (13) Western Central Plain Zone, (14) Southern Charyeong Plain Zone, (15) South Western Coastal Zone, (16) Southern Coastal Zone, (17) Northern Eastern Coastal Zone, (18) Central Eastern Coastal Zone, and (19) South Eastern Coastal Zone. The classification of agroclimatic zones for cropping systems was based on the rice agroclimatic zones considering zonal climatic factors for both summer and winter crops and traditional cropping systems. The agroclimatic zones were identified for cropping systems as follows: (I) Alpine Zone, (II) Mountainous Zone, (III) Central Northern Inland Zone, (IV) Central Northern West Coastal Zone, (V) Cental Southern West Coastal Zone, (VI) Gyeongbuk Inland Zone, (VII) Southern Inland Zone, (VIII) Southern Coastal Zone, and (IX) Eastern Coastal Zone. The agroclimatic zonal characteristics of climatic disasters under rice cultivation were identified: as frequent drought zones of (11) Yeongnam Basin Zone, (17) North Eastern Coastal Zone with the frequency of low temperature occurrence below 13$^{\circ}C$ at root setting stage above 9.1%, and (2) Taebaek Semi-Alpine Zone with cold injury during reproductive stages, as the thphoon and intensive precipitation zones of (10) Hanam Inland Zone, (15) Southern West Coastal Zone, (16) Southern Coastal Zone with more than 4 times of damage in a year and with typhoon path and heavy precipitation intensity concerned. Especially the three east coastal zones, (17), (18), and (19), were subjected to wind and flood damages 2 to 3 times a year as well as subjected to drought and cold temperature injury.

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Use of Human Serum Albumin Fusion Tags for Recombinant Protein Secretory Expression in the Methylotrophic Yeast Hansenula polymorpha (메탄올 자화효모 Hansenula polymorpha에서의 재조합 단백질 분비발현을 위한 인체 혈청 알부민 융합단편의 활용)

  • Song, Ji-Hye;Hwang, Dong Hyeon;Oh, Doo-Byoung;Rhee, Sang Ki;Kwon, Ohsuk
    • Microbiology and Biotechnology Letters
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    • v.41 no.1
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    • pp.17-25
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    • 2013
  • The thermotolerant methylotrophic yeast Hansenula polymorpha is an attractive model organism for various fundamental studies, such as the genetic control of enzymes involved in methanol metabolism, peroxisome biogenesis, nitrate assimilation, and resistance to heavy metals and oxidative stresses. In addition, H. polymorpha has been highlighted as a promising recombinant protein expression host, especially due to the availability of strong and tightly regulatable promoters. In this study, we investigated the possibility of employing human serum albumin (HSA) as the fusion tag for the secretory expression of heterologous proteins in H. polymorpha. A set of four expression cassettes, which contained the methanol oxidase (MOX) promoter, translational HSA fusion tag, and the terminator of MOX, were constructed. The expression cassettes were also designed to contain sequences for accessory elements including His8-tag, $2{\times}(Gly_4Ser_1)$ linkers, tobacco etch virus protease recognition sites (Tev), multi-cloning sites, and strep-tags. To determine the effects of the size of the HSA fusion tag on the secretory expression of the target protein, each cassette contained the HSA gene fragment truncated at a specific position based on its domain structure. By using the Green fluorescence protein gene as the reporter, the properties of each expression cassette were compared in various conditions. Our results suggest that the translational HSA fusion tag is an efficient tool for the secretory expression of recombinant proteins in H. polymorpha.

A Study on the Applicability of Soilremediation Technology for Contaminated Sediment in Agro-livestock Reservoir (농축산저수지 오염퇴적토의 토양정화기술에 대한 적용성 연구)

  • Jung, Jaeyun;Chang, Yoonyoung
    • Journal of Environmental Impact Assessment
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    • v.29 no.3
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    • pp.157-181
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    • 2020
  • Sediments from rivers, lakes and marine ports serve as end points for pollutants discharged into the water, and at the same time serve as sources of pollutants that are continuously released into the water. Until now, the contaminated sediments have been landfilled or dumped at sea. Landfilling, however, was expensive and dumping at sea was completely banned due to the London Convention. Therefore, this study applied contaminated sedimentation soil of 'Royal Palace Livestock Complex' as soil purification method. Soil remediation methods were applied to pretreatment, composting, soil washing, electrokinetics, and thermal desorption by selecting overseas application cases and domestically applicable application technologies. As a result of surveying the site for pollutant characteristics, Disolved Oxigen (DO), Suspended Solid (SS), Chemical Oxygen Demand (COD), Total Nitrogen (TN), and Total Phosphorus (TP) exceeded the discharged water quality standard, and especially SS, COD, TN, and TP exceeded the standard several tens to several hundred times. Soil showed high concentrations of copper and zinc, which promote the growth of pig feed, and cadmium exceeded 1 standard of Soil Environment Conservation Act. In the pretreatment technology, hydrocyclone was used for particle size separation, and the fine soil was separated by more than 80%. Composting was performed on organic and Total Petroleum Hydrocarbon (TPH) contaminated soils. TPH was treated within the standard of concern, and E. coli was analyzed to be high in organic matter, and the fertilizer specification was satisfied by applying the optimum composting conditions at 70℃, but the organic matter content was lower than the fertilizer specification. As a result of continuous washing test, Cd has 5 levels of residual material in fine soil. Cu and Zn were mostly composed of ion exchange properties (stage 1), carbonates (stage 2), and iron / manganese oxides (stage 3), which facilitate easy separation of contamination. As a result of applying acid dissolution and multi-stage washing step by step, hydrochloric acid, 1.0M, 1: 3, 200rpm, 60min was analyzed as the optimal washing factor. Most of the contaminated sediments were found to satisfy the Soil Environmental Conservation Act's standards. Therefore, as a result of the applicability test of this study, soil with high heavy metal contamination was used as aggregate by applying soil cleaning after pre-treatment. It was possible to verify that it was efficient to use organic and oil-contaminated soil as compost Maturity after exterminating contaminants and E. coli by applying composting.

Soil Physical Properties and Organic Matter (토양(土壤)의 물리성(物理性)과 유기물(有機物))

  • Im, Jeong-Nam
    • Korean Journal of Soil Science and Fertilizer
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    • v.11 no.3
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    • pp.145-160
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    • 1979
  • The effects of organic material application on soil physical properties were reviewed in relation to soil productivity. The organic matter contents and soil physical properties of the cultivated land in Korea were summarized and the effects of organic matter were compared in terms of land uses and soil types. Soil physical properties related to crop yield potential, such as soil aggregation, permeability, water holding capacity, erodibility, and compactibility, were used in evaluating the effects of organic materials as a soil physical amendment. The benefical effects of organic matter addition on soil physical conditions include (1) better aeration and increased infiltration in silty and clayey soils, (2) increased water holding capacity and moisture availability in sandy soils, (3) decreased soil erodibility, and (4) increased resistance to compaction. It is, therefore, concluded that continuous application of organic materials could greatly improve the various soil physical properties and favor the growth and yield of crops. A high rate of organic matter addition could contribute to reducing not only the soil erosion on sloping land, but also the possible detrimental effect of farm mechanization. In general, the effects of organic matter on soil physical improvement were estimated to be much higher in upland than in paddy. Organic matter would have a more pronounced effect on low productive lands such as heavy clayey or sandy soils and newly reclaimed soil. The optimum level of soil organic matter content was estimated to be about 3.0 to 3.5% for the best soil physical condition. Since the organic matter contents of the cultivated lands in Korea are much lower than optimum level, it would be desiable to use more organic materials to soil for the increase of soil productivity, continuation of stabilized high productivity and soil erosion control.

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