• Title/Summary/Keyword: middle adult

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Analysis of Educational Needs by Adult Life Cycle for Well-aging Education Program Development (웰에이징 교육 프로그램 개발을 위한 성인 생애주기별 교육 요구도 분석)

  • Ku, Jin-Hee;Lim, HyoNam;Kim, Doo-Ree;Kang, Kyung-hee;Kim, Seol-Hee;Kim, Yong-Ha;Lee, Chong-Hyung;Ahn, Sang-Yoon;Kim, Kwang-Hwan;Song, Hyeon-Dong;Hwang, Hey-Jeong;Kim, Moon-Joon;Park, A-rma;Jo, Gee-yong;Chang, Kyung-Hee;Cho, Young-Chae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.5
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    • pp.257-269
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    • 2021
  • This study aimed to secure basic data for the development and operation of well-aging education programs by analyzing the physical, mental, and socio-economic needs of well-aging education for successful aging. The research tool was developed as a questionnaire to investigate the perception of well aging and the needs of well-aging education in terms of physical, mental, and socio-economic aspects. In February 2021, 1949 adults over the age of 19 were surveyed through an online and mobile survey by Gallup Korea. Descriptive statistics analysis, variance analysis, Borich needs analysis, and IPA analysis were conducted to analyze the needs of well-aging education. The results revealed economic power, exercise, and chronic disease management to be high in terms of the overall priority of the education needs for well-aging, and infectious disease management, independence, and social responsibility were surveyed in the order of low education needs. In terms of economic power, education needs were highest among all age groups except for the middle-age group (35-49 years old), 82.4% of all respondents, and education needs for exercise and chronic disease management were highest in the middle-age group. Therefore, it is necessary to develop well-aging education programs for each life cycle. These results are expected to be used as empirical data in establishing a platform for developing and operating educational programs for well aging.

An Analysis of the Effect of the Residential Environment of Young Single-person Households on Residential Satisfaction and Life Satisfaction (청년 1인 가구의 주거환경이 주거와 삶의 만족도에 미치는 영향: 다른 연령 집단과의 비교를 중심으로)

  • Yongwook Kim;Saehim Kim;Joonwon Hwang;Mi-Jeong Cho
    • Land and Housing Review
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    • v.14 no.2
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    • pp.19-34
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    • 2023
  • The proportion of single-person households has been steadily increasing, and the young account for the highest proportion at 35.9% among all single-person households. However, research on young single-person households has been relatively recent. Research on single-person households has mostly focused on all single-person households or elderly single-person households, and comparative research between different age groups is lacking. Therefore, this study categorizes all single-person households into young, middle-aged, and elderly groups to investigate the differences in the factors that affect their residential satisfaction and to analyze how these residential environment factors affect life satisfaction through the mediating effect of residential satisfaction. The 2020 Seoul Survey Urban Policy Index Survey data were analyzed using a structural equation model to investigate the impact of each factor. First, a finding is that various residential environment factors directly affect residential satisfaction and life satisfaction. Next, it was found that residential satisfaction directly affects life satisfaction in the models of young and middle-aged single-person households. Through this, it was confirmed that there are differences in residential environment factors that affect residential satisfaction and that residential satisfaction plays an important mediating role. Finally, it was found that the factors that affect the residential and life satisfaction of young single-person households are more diverse compared to other age groups. This study provides policy implications that age group differences should be considered first in order to improve the residential and life satisfaction of single-person households. In particular, for young single-person households, it is necessary to consider more diverse alternatives to improve their residential and life satisfaction.

Spatial Genetic Structure of Needle Fir(Abies holophylla Seedlings on the Forest Gap Within a Needle Fir Forest at Mt. Odae in Korea) (오대산(五臺山) 전나무림(林)의 숲틈에서 발생(發生)된 전나무 치수(稚樹)들의 공간적(空間的) 유전구조(遺傳構造))

  • Hong, Kyung-Nak;Choi, Young Cheol;Kang, Bum-Yong;Hong, Yong-Pyo
    • Journal of Korean Society of Forest Science
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    • v.90 no.4
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    • pp.565-572
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    • 2001
  • The spatial genetic structure of Needle fir(Abies holophylla Max.) seedlings on forest gap within a Needle fir forest at Mt. Odae in Korea was analyzed on the basis of ISSR(inter-simple sequence repeats) marker analysis. The gap size was $1,500m^2(50m{\times}30m)$, and we sampled 416 one- or two-year-old seedlings by 2m intervals. Some trees at the upper crown layer except Needle firs and all trees at the middle and lower crown layers were removed, and Needle firs at the upper crown layer showed very weak growth strength or to be withering to death. The results of spatial autocorrelation using 31 polymorphic ISSR markers revealed that it was genetically homogeneous within spatial distance of 15.6m and the randomness of genetic distribution was from 15.6m to 31.2m. The genetic patch size of seedlings in forest gap might be restricted by the density of mother trees, making allow for the average height of adult Needle firs, the seed dispersal area, and the average distance between adults. For the directionality of seedling distribution, we investigated the variography using 'genetic configuration' which was the value of configuration in Multidimensional Scaling by genetic distance. In directional variogram, the increment of spatial distance from East to West direction was inversely proportional to genetic homogeneity. We presumed that this anisotrophy of seedling distribution at this forest gap resulted from the directionality of seed dispersal rather than the difference of fecundity between mother trees or the microhabitat variation, taking the evenness of forest floor condition, a vast seed production and the random distribution of seedlings at the studied site into consideration.

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A Study about the Change of Locations of the Center of Resistance According to the Decrease of Alveolar Bone Heights and Root Lengths during Anterior Teeth Retraction using the Laser Reflection Technique (Laser 반사측정법을 이용한 전치부 후방 견인시 치조골 높이와 치근길이 감소에 따른 저항중심의 위치변화에 관한 연구)

  • Min, Young-Gyu;Hwang, Chung-Ju
    • The korean journal of orthodontics
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    • v.29 no.2 s.73
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    • pp.165-181
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    • 1999
  • Treatment mechanics should be individualized to be suitable for each patient's personal teeth and anatomic environment to get a best treatment result with the least harmful effects to teeth and surrounding tissues. Especially, the change of biomechanical reaction associated with that of the centers of resistance of teeth should be considered when crown-to-root ratio changed due to problematic root resorption and/or periodontal disease during adult orthodontic treatment. At the present study, in order to investigate patterns of initial displacements of anterior teeth under certain orthodontic force when crown-to-root ratio changed in not only normal periodontal condition but also abnormal periodontal and/or teeth condition, the changes of the centers of resistance for maxillary and mandibular 6 anterior teeth as a segment were studied using the laser reflection technique, the lever & pulley force applicator and the photodetector with these quantified variables reducing alveolar bone 2mm by 2mm for each of maxillary 6 anterior teeth until the total amount of 8mm and root 2mm by 2mm for each of mandibular 6 anterior ones until the total amount of 6mm. The results were as follows: 1. Under unreduced condition, the center of resistance during initial displacement of maxillary 6 anterior teeth was located at the point of about $42.4\%$ apically from cemento-enamel junction(CEJ) of the averaged tooth of them and kept shifting to about $76.7\%$ with alveolar bone reduction. 2. The distance from the averaged alveolar crest level of maxillary 6 anterior teeth to the center of resistance for the averaged tooth of them kept decreasing with alveolar bone reduction, but the ratio to length of the averaged root embedded in the alveolar bone was stable at around $33\%$ regardless of that. 3. Under unreduced condition, the center of resistance during initial displacement of mandibular 6 anterior teeth was located at the Point of about $43\%$ apically from CEJ of the averaged tooth of them and this ratio kept increasing to about $54\%$ with root reduction. But the distance from CEJ to the center of resistance decreased from around 5.3mm to around 3.3mm, that is to say, the center of resistance kept shifting toward CEJ with the shortening of root length. 4. A unit reduction of alveolar bone had greater effects on the change of the centers of resistance than that of root did during initial Phase of each reduction. But both of them had similar effects at the middle region of whole length of the averaged root.

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Epidemiological Studios on Clonorchis sinensis Infection along the Nam-river in Gyeongnam Province, Korea (남강유역 간흡충감염의 역학적 조사연구)

  • 배경훈;안영겸
    • Parasites, Hosts and Diseases
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    • v.21 no.2
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    • pp.116-186
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    • 1983
  • An epidemiological study on Clonorchis sinensis infection along the Nam-river (total length ; 186km) flowing in Gyeongsang-nam-do, southern part of Korea, was carried out. Formalin-ether concentration technique and Stoll's egg counting method were employed to figure out the prevalence of C. sinensis infection. For the detection of cercariae from Parafossarulus sp., the snail host of C. sinensis, each snail was placed in aerated tap water, and examined for expelled cercariae. For observing the metacercariae the fresh water fish favorably eaten in raw conditions wore prepared by means of pressing the muscles between two slide glasses and/or by digesting them with artificial gastric juice. The fresh water fish were fed to the rabbits to get the worms and to identify the morphology of adult C. sinensis. The results are summarized as follows: 1. Overall Prevalence of C. sinensis infection was 38.75 from 5,291 examinees; 44.15 (1,408 out of 3,196) in male and 30.4% (637 out of 2,095) in female. 2. The prevalence rates were 42.0% at the upper stream, 41.2% around the vicinity of Jinyanglake, 34.2% at Jinju city, 34.2% at middle stream and 40.3% at down stream regions, respectively. 3. By age, the highest positive rate (53.4∼54.3%) was observed in 30 to 59 years of age. In this age group, the rate in males was 59.7∼62.2%, and in females 42.2∼44.4%, In the age group of less than 19 years it was 7.5∼20.9%. 4. By social strata, the positive rate was 16.5% in the primary school children, 22.6% in school students, 46.2% in teachers and local officers and 49.6% in the general inhabitants. 5. The quantitative examinations with the stool collected from clonorchiasis cases revealed that the light infection (less than 4,000/EPG) was 53.6%, moderate infection (4,001∼10,000 /EPG) 30.3% and heavy infection (more than 10,001/EPG) 16.1%, respectively. More than half of total cases examined were light infection, and 73.2% of female examinees were lightly infected with this cuke. 6. The average value of EPG was 4,963 (male, 6,057; female, 2,557 and the highest value was obtained from the age group of 30 to 59 years (5,240∼6,454). 7. The prevalence of Metagonimus yokogawai infection in humans was 5.5%, and 89.8% of metagonimiasis cases wore double-infected arith C. sinensis. The highest prevalence rate was observed in Jinju city (11.2%). 8. Total of 5,005 Parafossarulus sp., the snail intermediate host of C. sinensis, were examined for the detection of cercariae. The cercarial expulsion rate was 0.34%, and the snails collected in Jin-yang-lake side and in the down stream expelled mainly the cercariae of C, sinensis. 9. About 788 cercariaejday (range: 127∼1,503) were expelled daily from a snail naturally infected with C. sinensis. The snails which released more than 1,000 cercariae/day were 30.8% out of total collected. A snail uniquely released 5,840 cercariae/day in this study. 10. The other trematode cercariae besides C. sinensis were also detected, and the rates out of total snails were the cercariae of Losogenes liberum 6.71%, Cyathocotyle orientalis 0.26%, Notocotylus attenuatus 2.52% and Mucobucaris 0.54%, 11. Ten out of 18 species of fresh water fish caught along the river harbored the metacercariae of C, sinensis. The highest rate of metacercarial infection in fish was detected in Pseudorasbora larva (85.9%). The fish mainly eaten by the inhabitants along the Nam-river, and the metacercarial infection rates were: Zacco platypus 8.0%, Hemibarbus sp. 18.2∼26.7%, Gnathepcgcn sp. 37.5%, Ischikauia steenackeri 42.9% and Pseudogobio esocinus 16.7%. 12. Out of 36 P. larva, the number of metacercariae were about 109 (ranEe; 18∼446) per fish and 27 per gram of flesh. The fish caught in spring harbored the highest number of metacercariae. As indicated above, the prevalence of C. sinensis infection in the inhabitants residing around the Nam-river was relatively high. The farther toward the upper stream areas, the higher was the positive rate of C. sinensis infection, and most of clonorchiasis cases were lightly infected. The snail hosts of C. sinensis distributed all around the Nam-river. Several species of freshwater fish were infected with the metacercariae of C. sinensis and the infection rates were relatively high. To prevent C. sinensis infection in the endemic areas, the effective health education system is suggested as a control measure, although mass treatment is also expected to be useful, using chemotherapeutic agents such as "praziquantel", a recently developed anthelminthic for C. sinensis inftraction.

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The development direction of vocational education teachers' fostering of china based on vocational teachers specialization and vocational disciplines (직업교사 전문화 및 직업과학 학과발전에 기반한 중국 직업교육 교사양성 전망 -UNESCO '국제 직업교사 석사 교육과정 구성표준'을 중심으로-)

  • Yin, Zi-Long;Zhao, Zhi-Qun;Nam, Seung-Kwon;Choi, Won-Sik
    • 대한공업교육학회지
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    • v.35 no.2
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    • pp.70-81
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    • 2010
  • The purpose of this study is to introduce formation 'International framework curriculum for a Master Degree for TVET teachers and lectures' to present implications about fostering Chinese vocational teachers and to analyze the contents related to it. In 2004, UNFSCO composed formation International framework curriculum for a Master Degree for TVET teachers and lectures ("framework curriculum") to improve the ability of professionals in the vocational education and training fields including teachers and training leaders as well as to promote international academic exchange. Universities which introduce the framework curriculum should form specialized committee and carry out education considering the specific situation including other universities' situation, students' ability, educational certification system, etc. The framework curriculum should include the latest trends of the development of international vocational education science and carry out united educational learning between several internal or external high schools. UNFSCO tries to promote the development of educational learning and study of basic departments of vocational education such as vocational educational learning theory, vocational science, etc through the framework curriculum and to improve knowledge of vocational educational teachers and realize specialization of them. The number of universities that established the master's degree of vocational education in China is approx. 20 and the number of students that they collect every year. As for the plans of the master's degree of vocational teachers in each university, the courses about the practical problems like educational courses and educational learning are insufficient. But the framework curriculum thinks that educational learning of application theory is more important and emphasizes practice about the specific area and educational learning much more. Utilization of preceding experiences of advanced countries has the important meaning in search of models that foster Chinese vocational teachers and departmental system. The framework curriculum implies several useful points in installment of majors and educational process of the process that fosters Chinese vocational teachers.

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Position of maxillary central incisor and intercanine width in Korean adults (한국 유치악 성인의 상악 중절치 위치 및 견치간 거리에 관한 연구)

  • Yang, Dong-Hun;Lee, Jee-Yun;Ban, Jae-Sam;Oh, Gye-Jeong;Park, Sang-Won
    • The Journal of Korean Academy of Prosthodontics
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    • v.51 no.3
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    • pp.147-152
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    • 2013
  • Purpose: The aim of this study was to propose the position of maxillary anterior teeth and intercanine width measurements based on the incisive papilla in accordance with the cephalic type and gender of dentate Korean adult with normal teeth alignment. Materials and methods: 42 students with Class I normal occlusion, without crowding or spacing, were selected from the Chonnam National University School of Dentistry. The lateral skull radiographs of the subjects were taken and were classified as different cephalic types, based on their PFH / AFH ratios. 42 casts of their maxilla were prepared and both the distance between the upper central incisors and the middle of the incisor papilla was measured with a vernier caliper (A) and the distance between the maxillary canine cusp tips (B) were measured. Statistical analysis was performed using SPSS version 15 and their significance was investigated. Results: For dolichocephalic group, the mean values for A and B were 8.43 (SD: 0.61) and 36.73 (SD: 2.17), respectively. The mean value for A was 8.51 (SD: 1.27) for the mesocephalic group and 8.76 (SD 1.03) for the brachycephalic group. The mean value for B was 35.91 (SD: 1.86) for the mesocephalic group and 37.34 (SD: 2.23) for the brachycephalic group. For the male group, the mean A value was 8.86 (SD: 1.04) and the mean B value was 37.60 (SD: 0.24). For the female group, the mean A value was 8.41 (SD: 0.93) and the mean B value was 36.18 (SD: 2.01). The difference between male and female group in A values were not statistically significant (P>.05). The B values of the male subjects were greater than those of the female subjects and was statistically significant (P<.05). Conclusion: 42 students with normal dentition and occlusion in korea, the distance from the incisive papilla and the incisal edge of maxillary central incisors had no difference in cephalic type or gender. However, the distance between the cusp tip of both canines had significant difference in gender where the male showed higher values than the female, while having no difference in cephalic types.

A Study on Periodontal Disease and Tooth Loss in Metabolic Syndrome Patient (대사증후군 환자의 치주질환과 치아상실에 관한 연구)

  • Kang, Hyun-Joo
    • Journal of dental hygiene science
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    • v.15 no.4
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    • pp.445-456
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    • 2015
  • The aim of this study was to identify an effective control method of metabolic syndrome (MS) and oral diseases by investigating relationship between of MS and periodontal disease, tooth loss of the adult men and woman. We analyzed and concluded as follows, using a nationwide representative sample, in 8,225 middle senior citizens based on raw data of the 5th National Nutrition Survey in 2010, 2012. The data were analyzed by descriptive statistics, chi-squared test, and logistic regression using SAS ver. 9.2 program. The results are as follows, for correlation of metabolic component to periodontal disease, it was found that in men, the periodontal disease odds ratio of the group with abnormal fasting blood glucose increased 1.27 fold (95% confidence interval [CI], 1.04~1.54), and in woman, the odds ratios of the group with abnormal high density lipoprotein cholesterol increased 1.45 fold (95% CI, 1.22~1.72) and the odds ratio of the group with abnormal obesity increased 1.44 fold (95% CI, 1.17~1.77). For correlation of MS to periodontal disease, it was found that the odds ratio of periodontal disease in the woman at-risk group increased 1.55 fold (95% CI, 1.19~2.01) and that of the group with MS increased 2.25 fold (95% CI, 1.68~3.02). For correlation of woman's metabolic component to missing teeth, it was found that the odds ratio of group with abnormal blood pressure increased 1.41 fold (95% CI, 1.10~1.82). For correlation of woman's MS to missing teeth, it was found that the odds ratio of missing teeth in the group with MS increased 1.48 fold (95% CI, 1.07~2.04). It is considered that a public health project comprising preventive and systematic disease management is necessary for controlling MS and oral disease. The findings of the study are expected to lay the foundation for the development of oral health promotion programs.

Modeling and Validation of Population Dynamics of the American Serpentine Leafminer (Liriomyza trifolii) Using Leaf Surface Temperatures of Greenhouses Cherry Tomatoes (방울토마토에서 잎 표면온도를 적용한 아메리카잎굴파리(Liriomyza trifolii) 개체군 밀도변동 모형작성 및 평가)

  • Park, Jung-Joon;Mo, Hyoung-Ho;Lee, Doo-Hyung;Shin, Key-Il;Cho, Ki-Jong
    • Korean journal of applied entomology
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    • v.51 no.3
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    • pp.235-243
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    • 2012
  • Population dynamics of the American serpentine leafminer, Liriomyza trifolii (Burgess), were observed and modeled in order to compare the effects of air and tomato leaf temperatures inside a greenhouse using DYMEX model builder and simulator (pre-programed module based simulation programs developed by CSIRO, Australia). The DYMEX model simulator consisted of a series of modules with the parameters of temperature dependent development and oviposition models of L. trifolii were incorporated from pre-published data. Leaf surface temperatures of cherry tomato leaves (cv. 'Koko') were monitored according to three tomato plant positions (top, > 1.8 m above the ground level; middle, 0.9 - 1.2 m; bottom, 0.3 - 0.5 m) using an infrared temperature gun. Air temperature was monitored at the same three positions using a self-contained temperature logger. Data sets for the observed air temperature and average leaf surface temperatures were collected (top and bottom surfaces), and incorporated into the DYMEX simulator in order to compare the effects of air and leaf surface temperature on the population dynamics of L. trifolii. The initial population consisted of 50 eggs, which were laid by five female L. trifolii in early June. The number of L. trifolii larvae was counted by visual inspection of the tomato plants in order to verify the performance of DYMEX simulation. The egg, pupa, and adult stage of L. trifolii could not be counted due to its infeasible of visual inspection. A significant positive correlation between the observed and the predicted numbers of larvae was found when the leaf surface temperatures were incorporated into the DYMEX simulation (r = 0.97, p < 0.01), but no significant positive correlation was observed with air temperatures(r = 0.40, p = 0.18). This study demonstrated that the population dynamics of L. trifolii was affected greatly by the leaf temperatures, though to little discernible degree by the air temperatures, and thus the leaf surface temperature should be for a consideration in the management of L. trifolii within cherry tomato greenhouses.

Experimental and epidemiological studies on the life cycle of Echinostoma hortense Asada, 1926(Trematoda: Echinostomatidae) (남한강류역(南漢江流域)의 호르텐스극구흡충(棘口吸蟲) 감염실태(感染實態)와 생활사(生活史)에 관(關)한 연구(硏究))

  • Ahn, Yung-Kyum;Ryang, Yong-Suk
    • Parasites, Hosts and Diseases
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    • v.24 no.2
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    • pp.121-136
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    • 1986
  • Recently there have been some reports on human infections of Echinostoma hortense in Korea. It was found that a few species of freshwater fishes were playing the role of the second intermediate host of E. hortense. However, molluscan intermediate host has not been identified yet in Korea. The present study aimed to establish the life cycle of E. hortense in laboratory. Experimental studies such as egg production from the rat, development of the eggs in vitro, exposure of miracidia to freshwater snails, shedding pattern of cercariae from infected snails, morphology of cercariae, cercarial infection to the second intermediate host and infection of metacercariae to the definitive hosts were done. In addition, epidemiological surveys on the infection status in inhabitants and house rats, and on the natural infection of larval echinostomes in the snails and fishes were carried out along the South Hangang-river. The results obtained were as follows: 1. The eggs deposited from adults in physiological saline were cultivated at room temperature($20{\sim}24^{\circ}C$). The miracidia were firstly observed on 8 days after cultivation, and 85.5% of the eggs contained the mature miracidia on 11 days after cultivation. More than 90% formed the miracidia when cultivated at temperature $22{\sim}27^{\circ}C$. Hatching of the miracidia began on 12 days after cultivation and continued for a week. The size of the miracidia was $103.0{{\times}}51.4{\mu}m$ in average. The motility of the miracidia were active up to 8 hours after shedding, but they were all dead within 10 hours after shedding. 2. A freshwater snail, Radix auricularia coreana was cultivated in aquaria. A hatched $F_1$ snails from the egg masses were exposed to 20 miracidia respectively. Escape of cercariae started on 15 days after infecton. Radix auricularia coreana was experimentally identified as the first intermediate host of E. hortense in Korea. 3. Cercarial shedding started on $15{\sim}20$ days after infection by snail, continued for about 10 days (8.8 days in average). Infected snails were dead within 32 days after the miracidial infection. About 1,335 cercariae($328{\sim}1,994$) per snail were shed in its life, and 119 cercariae in average per snail per day were shed. The cercariae were motile for more than 24 hours, and then squirming at the bottom until death. The body and tail sizes of cercariae were $356{\times}186{\mu}m$ and $510{\times}68{\mu}m$ in average, respectively. The rediae parasitized in the snail hosts were found mainly around the pericardial regions, and their size was $1,575{\times}258{\mu}m$ in average. The numbers of developing cercariae in a mature redia were 14 in average ($7{\sim}20$ in range). The numbers of rediae in a snail were 102 in average on 15 days after miracidial infection and 221 in average on 28 days. 4. Three uninfected Misgurnus anguillicaudatus, less than 6.5cm long were used in for the cercarial infection. They were all exposed with 755 cercariae, and examined at 5-day intervals starting from 10 days after infection. All the fishes were infected with metacercariae of E. hortense and a total of 275 was found infected(36.4%). The metacercariae were fed to rats and the adult worms were obtained on 15 days after infection. 5. The infected rats began to deposit the eggs on 11 days after infection. The number of eggs deposited per day per worm (EPD/worm) was $400{\sim}500$ on 3 weeks after infection and was increased to $1,000{\sim}1,500$ on 4 to 17 weeks, then decreased to 800 on 21 weeks after infection. 6. A total of 745 stool specimens collected from 576 male and 169 female residents of 8 different villages along South Hangang basin was examined. Out of 745 specimens, the eggs of Echinostoma sp. were found in 2 cases (0.3%). Of 34 house rats one showed egg-positive (2.9%). 7. Total 971 Radix auricularia coreana collected from 7 sampling stations were examined for shedding of cercariae. Three snails (0.3%) shed the cercariae of E. hortense. A total of 119 out of 542 freshwater fishes (22.0%) had the metacercariae of E. hortense. The fishes parasitized with the metacercariae were 4 out of 14 examined species. The infection rates of 4 species were 34.1% (106 out of 311) in Misgurnus anguillicaudatus, 30.4% (7 out of 23) in Misgurnus mizolepis, 4.3% (2 out of 46) in Moroco oxycephalus and 22.2% (4 out of 18) in Odontobutis obscura interrupta. In summarizing the above results, the first intermediate host of E. hortense was found as Radix auricularia coreana in Korea. Also, it took about 46 days for the shortest completion of a life cycle of E. hortense in summer; that is, 10 days for miracidial development in eggs, 15 days for cercarial development in the snail, about 10 days for metacercarial development in the second intermediate hosts, and 11 days for the maturation as the adults in the definitive hosts. The natural infection rates of E. hortense in the intermediate hosts were relatively high but those in the definitive hosts were low in the middle areas of South Hangang basin.

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