• Korean Journal of Agricultural Science
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• v.12 no.2
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• pp.206-241
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• 1985

Attempts to search infection period, infection speed in the tissue of neck blast of rice plant, location of inoculum source and effects of several conditions about the leaf sheath of rice plants for neck blast incidence have been made. 1. The most infectious period for neck blast incidence was the booting stage just before heading date, and most of necks have been infected during the booting stage and on heading date. But $Indica{\times}Japonica$ hybrid varieties had shown always high possibility for infection after booting stage. 2. Incubation period for neck blast of rice plants under natural conditions had rather a long period ranging from 10 to 22 days. Under artificial inoculation condition incubation period in the young panicle was shorter than in the old panicle. Panicles that emerged from the sheath of flag leaf had long incubation period, with a low infection rate and they also shown slow infection speed in the tissue. 3. Considering the incubation period of neck blast of rice plant, we assumed that the most effective application periods of chemicals are 5-10 days for immediate effective chemicals and 10-15 days for slow effective chemicals before heading. 4. Infiltration of conidia into the leaf sheath of rice plant carried out by saturation effect with water through the suture of the upper three leaves. The number of conidia observed in the leaf sheath during the booting stage were higher than those in the leaf sheath during other stages. Ligule had protected to infiltrate of conidia into the leaf sheath. 5. When conidia were infiltrated into the leaf sheath, the highest number of attached conidia was observed on the panicle base and panicle axis with hairs and degenerated panicle, which seemed to promote the infection of neck blast. 6. The lowest spore concentration for neck blast incidence was variable with rice varietal groups. $Indica{\times}Japonica$ hybrid varieties were infected easily compared to the Japonica type varieties, especially. The number of spores for neck blast incidence in $Indica{\times}Japonica$ hybrid varieties was less than 100 and disease index was higher also in $Indica{\times}Japonica$ hybrid than in Japonica type varieties. 7. Nitrogen content and silicate content were related with blast incidence in necks of rice plants in the different growing stage changed during growing period. Nitrogen content increased from booting stage to heading date and then decreased gradually as time passes. Silicate content increased from booting stage after heading with time. Change of these content promoted to increase neck blast infection. 8. Conidia moved to rice plant by ascending and desending dispersal and then attached on the rice plant. Conidia transfered horizontally was found very negligible. So we presumed that infection rate of neck blast was very low after emergence of panicle base from the leaf sheath. Also ascending air current by temperature difference between upper and lower side of rice plant seemed to increase the liberation of spores. 9. Conidial number of the blast fungus collected just before and after heading date was closely related with neck blast incidence. Lesions on three leaves from the top were closely related with neck blast incidence, because they had high potential for conidia formation of rice blast fungus and they were direct inoculum sources for neck blast. 10. The condition inside the leaf sheath was very favorable for the incidence of neck blast and the neck blast incidence in the leaf sheath increased as the level of fertilizer applied increased. Therefore, the infection rate of neck blast on the all panicle parts such as panicle base, panicle branches, spikelets, nodes, and internodes inside the leaf sheath didn't show differences due to varietal resistance or fertilizers applied. 11. Except for others among dominant species of fungi in the leaf sheath, only Gerlachia oryzae appeared to promote incidence of neck blast. It was assumed that days for heading of varieties were related with neck blast incidence.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.1
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• pp.77-81
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• 2001

Necrotizing fasciitis is defined as infectious disease showing extensive necrosis of the superficial fascia with widespread involvement of the surrounding tissues and concurrent systemic toxicity. It is found commonly in the extremities, the trunk and the perineum, but shows extremely rare occurrence in the well vascularized area such as head and neck area. Occurred in the head and neck area, it is called "cervicofacial necrotizing fasciitis" (CFNF). It is a fatal disease which carries a mortality rate up to 60%. Early diagnosis, aggressive surgical debridement of necrotic tissues and massive antibiotics therapy are essential for achieving a favorable outcome. We present a case of cervicofacial necrotizing fasciitis in 35-year-old male patient with literature review.

• Journal of Chest Surgery
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• v.29 no.3
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• pp.350-354
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• 1996

Pulmonary mucormycosis is a very rare but often fatal opportunistic fungal infection caused by the order Mucorales in class Zygomycetes. Reported overall mortality exceeds 70% and the diagnosis is often made post-mortem. We experienced 2 cases of typical form of pulmonary mucormycosis. One patient was a poorly controlled diabetic and the other suffered from acute Iymphocytic leukemia (ALL). The former was diagnosed by a bronchoscopic biopsy and the latter by a pathologic examination from the percutaneous drain of a subphrenic abscess. Both of them underwent a surgical excision of the involved lung tissue. The patient with diabetes mellitus was successfully treated by surgical resection and discharged without complications. The other with ALL underwent a second operation and was transferred to the department of internal medicine for further management of his relapse of lettkemia. Recent literat re suggests that early aggressive diagnostic effort and treatment including surgical resection in the case of localized forms of the disease results in a good prognosis.

• Journal of Chest Surgery
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• v.34 no.3
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• pp.235-239
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• 2001

배경: 폐격리증, 선천성 낭성 유선종 기형, 기관지 낭종 선천성 엽기종 및 낭성 기관지 확장증 등의 폐에 발생하는 선청성 낭성 질환은 않으며 유사한 발생학적 및 임상적 양사을 가진다. 대상 및 방법: 1972년부터 1999년까지 본원 흉부외과에서 선청성 낭성 폐질환으로 수술받은 46명의 환자를 대상으로 병상 기록을 통한 임상상, 치료 및 병리소견을 검토하였다. 결과: 환자의 평균 연령은 16.2세 였고 남녀비는 17:29였다. 주 증상은 감염에 의한 발령이 11례, 호흡곤란이 10례 그리고 흉통과 가래 등이였고, 증상이 없었던 경우가 13례 였다. 질환은 폐격리증이 13례, 선청성 낭성 유선종 기형이 12례, 기관지성낭종이 12례, 낭성 기관지 확장증이 5례 그리고 선천성 엽기종이 4례였다. 수술은 단순 절계 8례, 폐구역 절제술 6례, 폐엽 절제술 31례 그리고 전폐 전제술 1례를 시행하였고 수술 사망은 폐엽 절제술은 시행한 7세된 기관지 낭종 환자로 수술직후 발생한 뇌경색으로 1례에서 발생하였으며 술후 합병증으로는 폐렴 4례와 지속적 공기누출과 농흉이 각 1례씩 이었다. 결론; 선청성 낭성 폐질환을 가진 환자들은 진단 즉시 수술하여 좋은 결과를 얻었다.

• Journal of The Korea Institute of Healthcare Architecture
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• v.24 no.2
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• pp.7-14
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• 2018

Purpose: The outbreak of Middle East Respiratory Syndrome(MERS) in KOREA has brought up the demands for ventilation guideline and regulations for healthcare facilities since most of the infection was spreaded inside healthcare facility. Currently KOREA has no ventilation guideline or regulations covering entire section of healthcare facility. The purpose of this study is to investigate current ventilation methods in KOREA healthcare facilities to in future, propose ventilation guideline. Methods: Research of foreign counties ventilation guideline and regulation for healthcare facilities were conducted for reference. Field investigation with survey of 21 healthcare were conducted to identify the ventilation system and operating methods. Additionally survey for healthcare workers were conducted to observe the recognition related to ventilation system in healthcare facility. Results: The result showed that most of foreign countries ventilation guideline and regulation suggests similar items to reduce the spread of infection and maintain good indoor air quality. The investigation results indicated that fixed guideline for ventilation in healthcare facility were required due to different ventilation operating methods. Survey result of healthcare workers has told us that ventilation guideline and regulation is needed to prevent further infection. Implications: Absence of ventilation guideline and regulations for healthcare facility in KOREA is an urgent issue.

• Journal of Chest Surgery
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• v.40 no.10
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• pp.711-714
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• 2007

Phlegmonous esophagitis is a disorder in which bacterial infection occurs in the submucosal and muscular layers of the esophagus. This malady is very rare and it is usually associated with high mortality. A 69-year-old male was admitted with chest pain and fever he'd experienced for 7 days. The chest computerized tomography scan revealed mediastinal widening, circumferential esophageal thickening, an air shadow along the esophagus and right pleural effusion. Drainage and debridement of the mediastinum and primary repair of the perforated esophageal muscular layer through a right thoracotomy was done immediately. Further surgical treatment was not performed. He had a good oral intake without dysphagia or esophageal leakage at discharge.

• Journal of the Korea Safety Management & Science
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• v.19 no.4
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• pp.115-123
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• 2017

Recently there is a growing interest in the airborne spread of virus. In particular, there is growing interest in secondary infection through the air in the hospital. The distribution of air-born virus depends on ventilation system installed in a hospital. In this study, simulations were carried out to predict the move of air-born virus by ventilation system at hospital. Simulation results showed that pressure distribution was -372.05Pa ~ -3.45 Pa at 1st floor incase of only used mechanical exhaust at bathroom, shower stall, storage, kitchen etc.. if ventilation switch from used mechanical exhaust to mechanical exhaust & mechanical supply. Simulation results showed that pressure distribution was -336.44Pa at stair hall < -0.2Pa at bathroom < mean 1.19Pa at other room. So simulation results showed that using all of the mechanical supply and mechanical exhaust was more effective then the mechanical exhaust for maintain the pressure distribution in hospital. It was also showed that when using the mechanical supply and mechanical exhaust more effectively prevention of air born virus diffusion.

• Land and Housing Review
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• v.13 no.3
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• pp.93-106
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• 2022

Ventilation plays an important role in controlling indoor air quality. Due to the recent spread of infectious diseases such as COVID-19 and with people spending more time indoors, there's been increased attention on the importance of ventilation performance. In many countries, ventilation is regulated by airflow rates and the number of air changes per hour (ACH). However, airflow rates and ACH alone do not provide an accurate account of actual indoor pollutant removal and ventilation uniformity in a space. This study looked into the ventilation performance of an actual residential unit using several sampling points instead of basing it off of airflow and air change rates. Literature review was used to derive relevant influencing factors and the tracer gas dilution method was used for the field test. The study measured air velocity, age of air, and ventilation efficiency at several locations and compared them to the average value at the center of the test space to determine the differences in ventilation performance at the selected measurement points. The study showed that different sampling locations resulted in different ventilation values. Findings of this study will be used to develop an experimental procedure for evaluating indoor ventilation performance of actual residential spaces.

• Particle and aerosol research
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• v.18 no.3
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• pp.51-59
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• 2022

In this work, virion concentration and its dose changes by HVAC and air cleaners were estimated in a subway station platform to control airborne infection of SARS-CoV-2. Collection efficiencies with particle size were measured for the air filter equipped in a HVAC in one subway station in Daejeon. Indoor PM_2.5 changes according to outdoor PM_2.5 with time were also measured to estimate air infiltration rate in the subway station platform. When infected persons generate virions by 10⁴, 10⁵, 10⁶, 3 × 10⁶ and 5 × 10⁶ h^-1 in a 2,400 m³ volume platform, the concentration and dose were estimated as 9, 92, 275 and 458 virions/m³ and 4, 43, 130 and 217 virions after 1 hour exposure, respectively. The concentration and dose were reduced by 70%, and 64%, respectively by operations of both HVAC (with a flow rate of 16,000 m³/h, MERV 11) and ten air cleaners(with total CADR 10,740 m³/h) compared to those without operation of both HVAC and air cleaners. However, virion dose in the platform was estimated to be too low at the general conditions due to a large space, a high air infiltration (3 h^-1) and a short residence time (usually < 10 mins) in the platform irrespective of the operations of HVAC or air cleaners. HVAC with filters and air cleaners would be more necessary in the concourse or shopping areas in the subway stations to reduce the infection dose from a few hundred to several tens virions in a hour.

• The Korean Journal of Mycology
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• v.12 no.3
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• pp.105-110
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• 1984

Seven seed samples of corn obtained from Kangweon Provincial Office of Rural Development, Kerea were tested for seed-borne fungi, and found that all the samples tested were infected with Fusarium moniliforme to an extent of $6.0{\sim}79.5%$. Severely infected seed samples showed poor germination on blotter. Seed component plating showed that the fungus present not only in tip caps, pericarps and endosperms, but also in embryos. Heavy infection of the fungus caused severe seed rot and seedling blight in soil, but the damage was not severe and many plants grew without any symptoms when the seeds with light infection were sown in soil. However the fungus was frequently detected from inside of the stems of healthy looking seedlings. The results indicate that the fungus transmit from seed to plant systemically. In inoculation experiments, the fungus produced stem rots on corn plants of 110 days old. The cultivar of Hwangok 3 was revealed more susceptible to the fungus than that of Suweon 19.