• Title/Summary/Keyword: Infectious Disease

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Comparison between Different Industrial GDPs to Understand the Importance of the Industry: Focusing on the Food, Medical & Drug Industry (산업별 GDP 중요도 비교 분석: 식의약 산업 부문 GDP를 중심으로)

  • Kim, Sohye;Kim, Jinmin;Kim, Jaeyoung;Kang, Byung-Goo
    • Knowledge Management Research
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    • v.22 no.4
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    • pp.103-118
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    • 2021
  • Gross Domestic Product(GDP) is affected by the economic power of each industry. Therefore, using statistical data related to the food and drug industry, we tried to determine the proportion of GDP and analyzed the impact of the food, medical & drug industry on the domestic economy through comparison with other industries. The food, medical & drug industry has a wide range of industries among domestic industries and is closely related to the lives of the people. In addition, human lifespan is increasing, and recently, due to the spread of an infectious disease called COVID-19, the bio sector belonging to the food, medical & drug industry is in the spotlight. Attention is needed to the industry as the competitiveness of the food, medical & drug industry is expected to increase. The Ministry of Food and Drug Safety provides statistics on the food, medical & drug industry, but does not provide a systematic share of GDP. Since it is difficult to determine how influential the industry is compared to other industries, this study attempts to obtain the share of GDP in the food, medical & drug industry and compare it with other industries. In the process of obtaining GDP in the food, medical & drug industry sector, there was a difficulty in that the figures in statistical data were not unified by time point. In order to overcome the limitations, statistical data as a standard are determined. The GDP of the Food, Medical & Drug Industry was estimated using total added value, production, sales, and added value by industry. Compared to other industries, the Food, Medical & Drug Industry's GDP ranked second after the GDP of the manufacturing industry. As a result, it suggests that the food, medical & drug industry has a great influence on the national economic power among domestic industries.

Clinical Presentation and Prognosis of SARS-CoV-2 Infection in Infants Aged ≤90 Days: Insights for Management During Outbreaks

  • Hye Jeong Moon;Mi Seon Han;Kyung Min Kim;Kyung Jin Oh;Ju Young Chang;Seong Yong Lee;Ji Eun Choi
    • Pediatric Infection and Vaccine
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    • v.30 no.2
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    • pp.84-90
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    • 2023
  • Purpose: Infants aged ≤90 days with fever are susceptible to severe infections. This study aimed to analyze the clinical features of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in this particular age group. Methods: Infants aged ≤90 days who were diagnosed with coronavirus disease 2019 (COVID-19) and hospitalized between March 1, 2020, and May 1, 2022 were included. Medical records of patients were retrospectively reviewed. Results: A total of 105 infants with COVID-19 were included; 27 (25.7%) neonates aged <28 days, and 48 (45.7%) and 30 (28.6%) infants aged 28-59 days and 60-90 days, respectively. Five (4.7%) patients remained asymptomatic and 68 (62.8%) were febrile, with a median fever duration of 2 days. The most common symptoms were respiratory including cough (66.6%), nasal stuffiness (51.4%), and rhinorrhea (40.9%). Blood cultures were performed in 10 infants but no organisms were detected. Cultures of bag-collected urine specimens from 8 infants were grown, resulting in positive growth for 2 without pyuria. Nine (8.6%) infants were treated with empirical antibiotics for a median duration of 2.3 days (range, 1-7 days). All 105 infants showed improvement without any complications, and there were no fatal cases. Conclusions: In this study, most infants aged ≤90 days with COVID-19 presented with mild symptoms and none of those evaluated had documented bacterial co-infection. The favorable prognosis among young infants with SARS-CoV-2 may aid clinicians in tailoring their approach to evaluation and management during outbreaks.

Etiology and Risk Factors of Community-Acquired Pneumonia in Hospitalized Children During the COVID-19 Pandemic in South Korea (국내 코로나19 판데믹 기간 발생한 입원을 요하는 소아청소년 지역사회폐렴의 원인과 위험 인자)

  • Hae Min Kang;Seung Ha Song;Bin Ahn;Ji Young Park;Hyunmi Kang;Byung Ok Kwak;Dong Hyun Kim;Joon Kee Lee;Soo-Han Choi ;Jae Hong Choi;Eun Hwa Choi;Ki Wook Yun
    • Pediatric Infection and Vaccine
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    • v.30 no.1
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    • pp.20-32
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    • 2023
  • Purpose: This study aimed to identify the etiology and risk factors of community-acquired pneumonia (CAP) requiring hospitalization in Korean children during the coronavirus disease 2019 (COVID-19) pandemic. Methods: Clinical information of children admitted with CAP to Seoul National University Children's Hospital (SNUCH) between January 1, 2021, and February 28, 2022, was retrospectively collected and analyzed. In addition, the etiologic diagnosis and demographic data of children with CAP who were discharged at the other seven hospitals between January and February 2022 were collected. Pneumonia was diagnosed using strict criteria comprising clinical symptoms, physical examination findings, and chest radiographic findings. Results: Among 91 children hospitalized with CAP at SNUCH during the 14-month period, 68.4% were aged <5 years and 79.1% had underlying diseases. Among the 95 CAP cases, respiratory assistance was required in 70.5%, and the use of a ventilator was required in 20.0%. A total of five patients expired, all of whom were either immunocompromised or had underlying neurological diseases. Neurological diseases and immunosuppression were significantly correlated with respiratory assistance (P=0.003) and death (P=0.014). A total of 55% of the detected respiratory pathogens were viruses, the most common of which was rhinovirus at 35.9%. Among the 169 children hospitalized for CAP at the eight institutions, ≥1 respiratory virus was detected in 92.3%, among which respiratory syncytial virus (79.8%) was the most prevalent. Conclusions: Even during the COVID-19 pandemic, Korean children were hospitalized with CAP caused by seasonal respiratory viral pathogens. Although atypical and pyogenic bacteria were not detected, continuous clinical monitoring and further prospective studies should be conducted.

Severe Human Rhinovirus Lower Respiratory Tract Infections in Young Children

  • Doo Ri Kim;Kyung-Ran Kim;Hwanhee Park;Esther Park;Joongbum Cho;Jihyun Kim;Hee Jae Huh;Kangmo Ahn;Nam Yong Lee;Yae-Jean Kim
    • Pediatric Infection and Vaccine
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    • v.30 no.3
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    • pp.111-120
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    • 2023
  • Purpose: Human rhinovirus (HRV) infections can result in lower respiratory tract infections (LRTIs). We aimed to investigate the characteristics of severe HRV LRTI in young children. Methods: Medical records were reviewed retrospectively in patients who were hospitalized for HRV LRTIs from 2016 to 2020 at the Samsung Medical Center in Seoul, Korea. Patients aged 90 days or older and younger than 5 years were included. Patients with co-infections with other respiratory pathogens were excluded. Severe HRV LRTI was defined as the following: the need for high-flow oxygenation, mechanical ventilation, or intensive care unit admission. Results: A total of 115 cases were identified. The median age was 17 months (range, 3-56 months) and the median hospital days were 4 days (range, 2-31 days). Of the 115 cases, 18 patients (15.7%) developed severe HRV LRTI. The median age was younger in the severe group compared to the non-severe group (9.5 months vs. 19.0 months, P=0.001). Of 18 patients with severe HRV LRTI, 11 (61.1%) had underlying diseases - chronic lung diseases accounted for the largest proportion (63.6%). Six patients (33.3%) required mechanical ventilation. Of note, 7 previously healthy children were diagnosed with severe HRV LRTI. Of those 7 children, 4 of them were diagnosed with asthma later. When the 115 cases were divided into previously healthy (n=60) and underlying disease (n=55) groups, severe courses of HRV LRTI were observed in 11.7% and 20.0% of children, respectively (P=0.219). Conclusions: HRV can cause severe LRTI even in previously healthy children as well as in children with comorbidities.

The National Survey of Acute Respiratory Distress Syndrome in Korea (급성호흡곤란증후군의 전국 실태조사 보고)

  • Scientific Subcommittee for National Survey of Acute Respiratory Distress Syndrome in Korean Academy of Tuberculosis and Respiratory Disease
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.1
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    • pp.25-43
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    • 1997
  • Introduction : The outcome and incidence of acute respiratory distress syndrome (ARDS) could be variable related to the varied definitions used for ARDS by researchers. The purpose of the national survey was to define the risk factors of ARDS and investigate the prognostic indicies related to mortality of ARDS in Korea according to the definition of ARDS determined by the American-European Concensus Conference on 1992 year. Methods : A Multicenter registry of 48 University or University-affliated hospital and 18 general hospital s equipped with more than 400 patient's beds conducted over 13 months of patients with acute respiratory distress syndrome using the same registry protocol. Results : 1. In the 12 months of the registry, 167 patients were enrolled at the 24 hospitals. 2. The mean age was 56.5 years (${\pm}17.2$ years) and there was a 1.9:1 ratio of males to females. 3. Sepsis was the most common risk factors (78.1%), followed by aspiration (16.6%), trauma (11.6%), and shock (8.5%). 4 The overall mortality rate was 71.9%. The mean duration was 11 days (${\pm}13.1$ days) from the diagnosis of ARDS to the death. Respiratory insufficiency appeared to be a major cause in 43.7% of the deaths followed by sepsis (36.1%), heart failure (7.6%) and hepatic failure (6.7%). 5. There were no significant differences in mortality based on sex or age. No significant difference in mortality in infectious versus noninfectious causes of ARDS was found. 6. There were significant differences in the pulse rate, platelet numbers, serum albumin and glucose levels, the amounts of 24 hour urine, arterial pH, $Pa0_2$, $PaCO_2$, $Sa0_2$, alveolar-arterial oxygen differences, $PaO_2/FIO_2$, and PEEP/$FI0_2$ between the survivors and the deaths on study days 1 through 6 of the first week after enrollment. 7. The survivors had significantly less organ failure and lower APACHE III scores at the time of diagnosis of ARDS (P<0.05). 8. The numbers of organ failure (odd ratio 1.95, 95% confidence intervals:1.05-3.61, P=0.03) and the score of APACHE III (odd ratio 1.59, 95% confidence interval:1.01-2.50, P=0.04) appeared to be independent risk factors of the mortality in the patients with ARDS. Conclusions : The mortality was 71.9% of total 167 patients in this investigation using the definition of American-European Consensus Conference on 1992 year, and the respiratory insufficiency was the leading cause of the death. In addition, the numbers of organ failure and the score of APACHE III at the time of diagnosis of ARDS appeared to be independent risk factors of the mortality in the patients with ARDS.

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A Comparative Study on the Pattern of Outpatient Department Utilization at a Tertiary Level Hospital before and after Implementation of the Patient Referral System (의료전달체계 실시 전후의 3차 진료기관 외래환자 이용양상 비교)

  • Lee, Kyeong-Soo;Kim, Chang-Yoon;Kang, Pock-Soo
    • Journal of Preventive Medicine and Public Health
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    • v.25 no.1 s.37
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    • pp.88-100
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    • 1992
  • This study was conducted to assess the effects of implementation of the patient referral system started July 1st, 1989. A comparison on the pattern of outpatient services of the Departments of Internal Medicine, General Surgery, and Pediatrics at the Yeungnam University Hospital was conducted for each one year period before and after implementation of the patient referral system. The pre-implementation period was from July 1, 1988 to June 30, 1989 and the post-implementation period was from July 1, 1989 to June 30, 1990. The information used for this study was obtained from official forms, prepared by the Yeungnam University Hospital, and submitted to the Korean Medical Insurance Cooperatives. After implementation of the patient referral system, the number of outpatient cases in the Department of Internal Medicine decreased 36.1% from 9,669 cases to 6,181 cases a year. Cases in the Department of General Surgery decreased 23.7% from 1,864 cases to 1,422 cases a year. The number of cases in the Department of Pediatrics decreased 36.9% from 3,372 cases to 2,128 cases a year. After implementation of the patient referral system, the average age of cases in the Departments of Internal Medicine and General Surgery was 52.5 and 49.7 years old, respectively. This was a significant increase in comparison with the pre-implementation period. After implementation of patient referral system, the proportion of new outpatients in the Department of Internal Medicine decreased from 24.1% to 14.6%, the Department of General Surgery from 36.0% to 23.4%, and the Department of Pediatrics from 15.5% to 8.3%. The number of visits per case decreased significantly in the Department of Internal Medicine(from 1.74 to 1.61), but there was no significant change in the Departments of General Surgery and Pediatrics. The length of treatment per case increased significantly in all three departments(from 16.1 days to 19.3 days in the Department of Internal Medicine, from 12.0 days to 15.2 days in the Department General Surgery, and 8.9 days to 11.2 days in the Department of Pediatrics). The number of clinical tests per case increased significantly in the Department of Internal Medicine (from 2.2 to 2.5), in the Department of Pediatrics(from 0.8 to 1.1) and increased in the Department of General Surgery(from 6.4 to 6.6). The average medical cost per case decreased from 43,900 Won to 42,500 Won in the Department of Internal Medicine, while the cost increased from 75,900 Won to 78,500 Won in the Department of General Surgery and from 12,700 Won to 13,500 Won in the Department of Pediatrics. In case-mix, the chronic degenerative disease(i. e. hypertension, diabetes mellitus, angina pectoris, malignant neoplasm, and pulmonary tuberculosis) ranked higher and acute infectious diseases and simple cases(i. e. gastritis and duodenitis, haemorrhoids, anal fissure, carbuncle, acute URI, and bronchitis) ranked lower after implementation of the patient referral system compared to before implementation.

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Role of Invasive Procedures in the Diagnosis and Management of Pulmonary Infiltrates in Patients with Leukemia (백혈병 환자에서 발생한 폐침윤의 진단 및 치료에 있어 침습적 검사의 역할)

  • Kang, Soo-Jung;Park, Sang-Joon;An, Chang-Hyeok;Ahn, Jong-Woon;Kim, Ho-Cheol;Lim, Si-Young;Suh, Gee-Young;Kim, Ho-Joong;Kwon, O-Jung;Lee, Hong-Ghi;Rhee, Chong-H.;Chung, Man-Pyo
    • Tuberculosis and Respiratory Diseases
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    • v.48 no.4
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    • pp.448-463
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    • 2000
  • Background : Pulmonary infiltrate is a frequent cause of morbidity and mortality in patients with leukemia. It is often hard to obtain a reliable diagnosis by clinical and radiologic findings alone. The aim of this study was to evaluate diagnostic and therapeutic benefits of invasive procedures for new lung infiltrates in leukemia. Methods : Patients with leukemia who developed new lung infiltrates from December 1994 to March 1999 were included in this study. These patients were classified into the empirical group who received empirical therapy only and into the invasive group who underwent bronchoscopy or surgical lung biopsy for the diagnostic purpose of new lung infiltrates. A retrospective chart review was done to find the etiologies of new lung infiltrates, the yield of invasive procedures, outcome as well as predicting factors for survival. Results : 1) One hundred-two episodes of new lung infiltrates developed in 90 patients with leukemia. Invasive procedures were performed in 44 episodes while 58 episodes were treated with empirical therapy only. 2) Invasive procedures yielded a specific diagnosis in 72.7%(32/44), of which 78.1% had infectious etiology. Therapeutic plan was changed in 52.3%(23/44) of patients after invasive procedures. None of them showed procedure-related mortality. 3) The overall survival rate was 62.7%(64/102). Survival rate in the invasive group (79.5%) was significantly better than that in the empirical group (50.0%) (p=0.002). 4) Upon multivariate analysis, the performance of invasive procedures, no need for mechanical ventilation and achievement of complete remission of leukemia after induction chemotherapy were the independent predicting factors for survival in patients with leukemia and new lung infiltrates. Conclusion : Bronchoscopy and surgical lung biopsy are useful in the diagnosis of new lung infiltrates in patients with leukemia. However, survival benefits of invasive procedures should be considered together with disease status of leukemia and severity of respiratory compromise.

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Investigation of Poultry Farm for Productivity and Health in Korea (한국에 있어서 양계장의 실태와 닭의 생산성에 관한 조사(위생과 질병중심으로))

  • 박근식;김순재;오세정
    • Korean Journal of Poultry Science
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    • v.7 no.2
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    • pp.54-76
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    • 1980
  • A survey was conducted to determine the status of health and productivity of poultry farms in Korea. Area included Was Kyunggido where exist nearly 50% of national poultry population. From this area, 41 layer and 34 broiler farms covering 21 Countries were selected randomly for the survey. When farms were divided in the operation size, 95.1% of layer and 82.3% of broiler farms were classified as business or industrial level while the rest were managed in a small scale as part time job. Generally layer farms had been established much earlier than broiler farms. Geographically 10.7% of layer farms were sited near the housing area such as field foreast and rice field. No farms were located near the seashore. The distance from one farm from the other was very close, being 80% of the farms within the distance of 1km and as many as 28% of the farms within loom. This concentrated poultry farming in a certain area created serious problems for the sanitation and preventive measures, especially in case of outbreak of infectious diseases. Average farm size was 5,016${\times}$3.3㎡ for layers and 1,037${\times}$3.3㎡ for broilers. 89.5% of layer ana 70.6% of broiler farms owned the land for farming while the rest were on lease. In 60% of layer farms welters were employed for farming while in the rest their own labour was used. Majority of farms were equipped poorly for taking necessary practice of hygiene and sanitation. The amount of disinfectant used by farms was considerably low. As many as 97.6% of lave. farms were practised with Newcastle(ND) and fowl pox(F$.$pox) vaccine, whereas only 43.6% and 5.1% of broiler farms were practised with ND and F$.$pox vaccine, respectively. In 17-32.7% of farms ND vaccine was used less than twice until 60 days of age and in only 14.6% of farms adult birds were vaccinated every 4months. Monthly expense for preventive measures was over 200,000W in 32% of farms. Only 4.9-2.7% of vaccine users were soaking advice from veterinarians before practising vaccination, 85% of the users trusted the efficacy of the vaccines. Selection of medicine was generally determined by the farm owner rather than by veterinarans on whom 33.3% of farms were dependant. When diseases outbroke, 49.3% of farms called for veterinary hospital and the rest were handled by their own veterinarians, salesmen or professionals. Approximately 70% of farms were satisfied with the diagnosis made by the veterinarians. Frequency of disease outbreaks varied according to the age and type of birds. The livabilities of layers during the period of brooding, rearing ana adultwere 90.5, 98.9 and 75.2%, respectively while the livalibility of broilers until marketing was 92.2%. In layers, average culling age, was 533.3 day and hen housed eggs were 232.7. Average feed conversion rates of layers and broilers were 3.30 and 2.48, respectively. Those figures were considerably higher than anticipated but still far lower than those in developed countries.

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Consideration on National Rituals and Folk Beliefs Found in 『Hajaeilgi』 (『하재일기』에 나타난 국가의례와 민간신앙 일고찰)

  • Song, Jae Yong
    • (The)Study of the Eastern Classic
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    • no.69
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    • pp.349-371
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    • 2017
  • "Hajaeilgi(荷齋日記)" was written by Ji Gyu-sik, a gongin of Saongwon(司饔院)'s branch, almost everyday for 20 years and 7 months from January 1st, 1891 until the leap month of June 29th, 1911. It deals with many different areas including domestic and foreign circumstances, custom, rituals, all the affairs related to the branch, and also everyday life events he did see or hear about. Particularly, Ji Gyu-sik did not belong to the yangban class, and we can hardly find diaries written by such class' people. Here, what this author pays attention to among the things written in "Hajaeilgi" is the contents about folklore. Ji Gyu-sik wrote in his "Hajaeilgi" about things related to folklore, for example, seasonal customs, folk plays, rituals, or folk beliefs that were actually practiced then as a person not belonging to the yangban class. Such diaries are rare, and its value is highly appreciated as a material, and it is meaningful in the aspects of folklore as well. Therefore, as part of the work to look into folklore found in "Hajaeilgi", this author focuses on national rituals and folk beliefs in it. The things that have been discussed earlier can be summed up as follows: About national rituals, it is sorry that it only deals with the emperor's enthronement and emperor and crown prince's birthday in garye(嘉禮); however, it is meaningful to know that the people faithfully carried out national ceremonies and celebrations then. Particularly, it is noteworthy that during the national ceremonies or celebrations, students were asked to sing the national anthem. About hyungrye(凶禮), only it deals with the court funeral rite. Aside from Minbi's funeral rite, the court funeral rite was performed properly at the right time according to the procedure like before, and also, it seems that the people fulfilled it faithfully by order of the government. Also, it can be learned from it that Japanese killed Minbi, burned the body with oil, and left the ashes behind. About folk beliefs, the branch held a memorial service at the shrine of the town regularly. The town, too, performed Gocheongsinsa each year. The money needed for the memorial service was collected from the town people differently according to their financial situations, and they prepared for jesu for the ancestral rite altogether. The memorial service was carried out in Sansindang or Bugeundang, too, and it was common that they summoned a shaman to perform a gut. The diary is valuable as material. After being a Christian, Ji Gyu-sik once tried to abolish sinsa jesa held in hoesa and get rid of saesin(賽神), that is, a gut or pudakgeori, but he had no choice but to follow the precedent. Meanwhile, it is also noteworthy that when the town suffered from floor and infectious disease, Ji Gyu-sik installed an altar in front of his house for the town's wellbeing and health, prepared for jesu including offerings and drinks, and held a memorial service to Hwangcheonhuto(皇天后土; the gods of heaven and earth) accompanied with the town people. Also, when he had any hardships in his family, Ji Gyu-sik summoned a shaman for a gut or offered a devout prayer to the mountainous god. Such shamanism or the things like worshiping Gwanseongjegun(關聖帝君) mostly in the beginning of January and telling fortunes about the year were all folk beliefs. This was very popular among the people, and it seems that it was deeply rooted in his life as well. Also, Ji Gyu-sik supported Fengshui beliefs, and it seems that it is not different from the people's general tendencies, either. As described above, "Hajaeilgi" dealing with national rituals and folk beliefs in it is valuable as material and is meaningful for research on forklore, and moreover, it is also significant in the aspects of forklore as well.

Studies on Neck Blast Infection of Rice Plant (벼 이삭목도열병(病)의 감염(感染)에 관(關)한 연구(硏究))

  • Kim, Hong Gi;Park, Jong Seong
    • 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.

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