• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.2
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• pp.144-152
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• 2005

To evaluate the effect of lead biomarkers including bone lead on neurobehavioral test in lead workers, 652 lead workers without any occupational exposure to organic solvent, mercury and arsenic were agreed to participate this study. For the control subjects 102 non-occupationally lead exposed blue collar workers in general manufacturing industries were also joined this study. All study subjects joined this study with written informed consent. The study variables of lead exposure were blood and patella lead. For the general characteristics of study subjects, standardized questionnaire regarding age, sex, past disease history, job duration, body mass index (BMI), drinking and smoking habit were provided. For the past history of neurotoxicity related diseases, all study subjects were interviewed by qualified occupational health physician. The results obtained were as follows: 1. Compared with controls without occupational lead exposure, lead exposed subjects had worse performance on all tests(p<0.05). 2. After adjustment for covariates (age, sex, job duration, education level, BMI, smoking and drinking status), the signs of the regression coefficients for blood lead were negative for 13 of the 14 tests. Blood lead was a significant predictor of poorer scores on 8 tests (simple reaction time(ms & root MSD), Trail-Making Test B, Digit Symbol Substitution, Purdue Pegboard assembly, Digit Span Test, Benton Visual Retention, and Purdue pegboard both hand). 3. After adjustment for covariates (age, sex, job duration, education level, BMI, smoking and drinking status), the signs of the regression coefficients for patella lead were negative for 12 of the 14 tests. Patella lead was a significant predictor of poorer scores on 8 tests (simple reaction time(ms). Purdue Pegboard assembly, Digit Span Test, Benton Visual Retention. Pursuit Aiming rest (no. of correct & no. of incorrect), Purdue pegboard non-dominant hand and both hand). With above results, blood lead and patella lead were associated with poorer performance of neurobehavioral tests. In addition, patella lead was confirmed to be better predictor of manual dexterity test in neurobehavioral test battery in lead workers

• Parasites, Hosts and Diseases
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• v.22 no.2
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• pp.181-189
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• 1984

The metacercariae of Echinostoma cineterchis (Trematoda: Echinostomatidae) were found infected in the loaches (Misgurnus anguillicaudatus) purchased from two local markets in Korea. Identification of the metacercariae was done after obtaining adult worms from experimentally infected albino rats. Brief course of worm development in rats was also observed up to 28th post-infection day. The results are as follows: 1. The metacercariae of E. cinetorchis were detected from 5 (10.9%) out of 46 loaches examined and the average metacercarial burden per infected loach was 34.4. They were always found from the posterior abdominal wall. 2. The worm recovery rate from 8 rats was 24.6% in average. It was observed that the rate decreased according to age of infection; from 40.7% after 6 days to 15.0% after 28 days. 3. The adult worms were morphologically characterized by the presence of head crown with derfally uninterrupted collar spines, 37-38 in number, and the tendency of migration or disappearance of testes. So that they were identified as Echinostoma cinetorchis Ando et Ozaki, 1923. 4. The development of worm was very rapid during 6-10 days after infection and became much slower thereafter. During the rapid worm growth the development of genital organs was more prominent than that of non-genital organs. From the results it is concluded that the loach is involved in the life cycle of E. cinetorchis in this country and may take a role for infection source to animals and man. It is also confirmed that migration or loss of testes is the distinct specific character of this echinostomatid fluke.

• Parasites, Hosts and Diseases
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• v.29 no.2
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• pp.161-172
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• 1991

The complete life cycle of Echinostoma hertense has been maintained in the laboratory, using Lymnaea persia snails and Rana nigromaculata tadpoles as the first and second intermediate hosts. ICR mice was used as the definitive host. Within the egg of 5. hotense, the miracidium was fully matured in 13 days of incubation at $29~30^{\circ}C$. The miracidium was $93.8{\times}53.6{\;}{\mu\textrm{m}}$ in average size, covered with numerous cilia of $7~11{\;}{\mu\textrm{m}}$ length. The epidermal plates were arranged in 6-8-4-2 formula. The first generation rediae ($1.19{\times}0.27{\;}mm$ in average size) were observed in 14 days after miracidial challenge to the snails, and the second generation rediae ($1.40{\times}0.26{\;}mm$ in average size) in 30 days. The average sixte of the cercaria was $295.5{\times}145.0{\;}{\mu\textrm{m}}$. Their head crown was poorly developed, and collar spines were not yet observed. After a cercarial challenge to the tadpoles, all of the tadpoles became infected and the average worm recovery rate was 88.5%. The majority of the metacercariae (75.5%) were recovered from the muscle of the tadpole's posterior body and the rest (24.3%) from their gills. The metacercariae from the tadpoles were elliptical, and $167.7{\times}129.9{\;}{\mu\textrm{m}}$ in average size. The recovery rate of adults from the mice was difFerent by the age of the metacercariae grown in the tadpoles. The metacercariae younger than 5 hrs could not infect mice whereas those older than 6 hrs could infect mice. The recovery rate became higher as the metacercaria matured, with the peak recovery rate of 90.0 % at the metacercarial age of 9 days. Thereafter the recovery rate decreased to 55.0% at the age of 50 days. As shown by the above results, the whole life cycle of E. hcrtense has been completed in the laboratory. At least 55~58 days were required to maintain one egg-to-egg cycle of E. hortense.

• Journal of Korean Public Health Nursing
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• v.5 no.1
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• pp.5-22
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• 1991

This study was conducted to provide information of affective area in developing a nursing curriculum. The sample consisted of 38 sophomores and 43 seniors in Department of Nursing, College of Medicine, Han Yang University. Data were collected by using a structured questionnaire, which consisted of social, home and self control aspects in self concept. The results are summarized as follows; 1. CD In sophomore, as father's academic career were higher, the self concept In social aspects became higher. The students whose father's job was profesion and a white-collar job and who applied for nursing by force and were satisfied with their educational expenses had more positive self concept in social aspects. In senior, as their age were higher, the self concept in social aspects became higher. The students who had religion, recognized the visions of nursing, and were satisfied with their major, had more positive self concept in social aspects. In self concept in social aspects, home environment explained the major variable in sophomore. On the other side, the variable related to major was important in senior. (2) In sophomore, the students who were satisfied with educational expenses and their major had more positive self concept in home aspects. In senior, the students who counseled of their problems with their parents and recognized the visions of nursing had more positive self concept in home aspects. Counsel of their personal problem with their parents explained the most affective variable $(9.6\%)$ for self concept in home aspects in senior. But, it explained only $1.1\%$ of the variance for self concept in home aspects in sophomore. (3) In senior, the students who were unsatisfied with their educational expenses had more negative self concept in self control aspects. 2. There was no significant difference accord ing to the academic year m social, home and self control aspects. 3. The aspects with the highest positive perception of the self concept was home aspects. Self concept in social aspects was more positive perception than in self control aspects. Self concept in self control aspects was lower than in other aspects. 4. Significant relationship a revealed between social aspects and home aspects in sophomore. In senior, the positive correlation were found between social aspects and home aspects and between social aspects and self control aspects. In conclusion, the self concept m home aspects was more positive perception than in other aspects. It resulted from the fact that the nursing uniqueness was based on the spirit of humanity and service. But, when we consider social and self control aspects, good relationship between subjects and nurse is important in nursing, so it is desirable that nursing curriculum include human relationship program. Therefore. in order to strengthen positive self concept, professors and parents must pay attention to student's problems and counsel with then is required.

• Journal of the Economic Geographical Society of Korea
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• v.4 no.2
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• pp.1-22
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• 2001

The object of this research is to explain types and factors of locations and regional linkages of manufacturing firms in rural areas using Eumsung County as a case of rural areas. Eumsung County is now vigorously industrializing owing to the government policy dispersing factories in the Capital region. The results of the survey conducted on industrial firms in Eumsung County through questionnaires reveal that individual sites are dominantly preferred by factory owners in comparison to the designated industrial complexes because the former is cheaper in land price. The main factors of industrial location in Eumsung County are cheap land cost, convenient highway accessibility, and the dispersion policy of the Capital region. In terms of the regional linkage, the proportion of the linkage with other regions is larger than that within the local region in case of purchasing raw materials, but the linkage with other regions is lower than that within the local regions in case of selling products. Also most white collar employees in Eumsung County were revealed to reside in and around the Capital region. In order to develop and maintain industrial firms in rural areas so as to avoid "dependency development," efforts for improving of the linkages between the local firms and expanding of social overhead capital are necessary.necessary.

• Journal of Environmental Health Sciences
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• v.5 no.1
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• pp.10-17
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• 1978

Recently this writer has conducted a comprehensive survey of 38 private businesses where group feeding is practiced, with a view to determining the condition of nutrition intake by the blue collar workers of these businesses firms as well as gaining an indication of their facilities management along with their sanitary precautions. The survey has revealed, among others, a number of interesting data such as shown below. 1. There are a total of 1,054 workers being fed in groups daily at each of the above business companies, with only one nutrition specialist regardless of the number of workers to be fed or the number of times they are fed daily. The average number of cooks comes to 2.7 persons per 100 workers, while 42.2% of the companies provide four meals a day including mid-night supper, with the result that the workers are fed 3.13 times a day on an average. 2. The average feeding cost amounts to 151 won per meal per person, of which 86 won is payed by the workers themselves and 115 won by the companies involved. 3. The average fbod intake has been found to be 490 grams which can be further broken down into 44grams of animal food and 446grams of vegetable food. These figures are higher than those revealed by the 1975 investigation of the nation's average nutrition intake. 4. The survey also shows the daily calorie consumption per person to be as high as 896 calories including 37 grams of protein which is further broken down into 11 grams of animal protein and 26grams of vegetable protein. With respect to other types of nutrients excepting Vitamin-A, the companies concerned are believed to prorids more than what the survey of the nation's nutrition has revealed or the amount recommended by Korea FAO assoc!ation as desirable. 5. As for facilities management, there is still much room for future improvement. Some 97.4% of the companies surveyed are not equipped with the steam table, which indicates lack of concern along this line as well as a very how degree of equipment utilizations. Distribution of the food in the dining room is generally depedent on self-service method. 6. Speaking of sanitary precautions taken by those businesses involved, some 76.3% are found to have their compounds haunted by rats and other insects. Some 73.7% of them are dependent on boiling method for disinfection of kitchen utensils, which is conducted by 50% of those industries only two or three times a week. It seems hardly feasible to conduct disinfection everyday.

• Journal of Korean Society of Forest Science
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• v.96 no.1
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• pp.107-114
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• 2007

Establishments of the seedlings inside the natural forest from adjacent artificial forests would be an important factor in forest stand dynamics. This study was conducted to see the invasion of Korean pine (Pinus koraiensis) seedlings which is not native in this region, into the natural deciduous broad-leaved forest in Gwangneung, Korea. There is no mother tree at the I ha study site while the number of naturally regenerated P. koraiensis seedlings was 345 trees and 56% of them were clumped with more than two seedlings at each point. Applying the image segmentation method to IKONOS satellite image of January, 2003, the distance from the center of 1 ha study site to the nearest mother tree and plantation of Korean pine were 200 m and 270 m, respectively. The average height and root-collar diameter of the seedlings were 34 em and 7 mm, respectively and the age of 207 seedlings (60%) were below 5 years old. Most abundant range of soil moisture gradient and LAl (leaf area index) were from 16 to 20% and those of LAI were from 3.1 to 3.5. To understand the dynamics and seed dispersal pattern of Korean pine in the Gwangneung natural deciduous broad-leaved forests, additional studies not only long-term monitoring of growth and mortality of naturally regenerated Korean pine seedlings but also application of stable isotope analysis and molecular genetic techniques was recommended.

• Journal of Bio-Environment Control
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• v.26 no.3
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• pp.167-174
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• 2017

To identify the appropriate irrigation level for Pinus densiflora, a common reforestation species in Korea, we investigated their growth response characteristics according to different irrigation treatment levels for producing container seedlings with relatively high growth rate for higher survival rate when planted at the reforestation site. The container seedlings including control seedlings (no irrigation was applied) were grown in 104-cell trays were irrigated for 8 weeks from 15 weeks after seeding, at intervals of 1, 2, 3, 5, 7, 10, and 15 days. Analysis of the height growth, root collar diameter growth, and dry matter production of the container seedlings according to irrigation showed that the highest growth reaction was observed for the irrigation interval of 1 day. A shorter irrigation cycle resulted in better growth of the container seedlings, but overall, longer total root length were observed with an irrigation cycle of 3 days compared with cycles of 1 or 2 days. Quality index (QI) was the highest for the irrigation interval of 1 day, and tended to decrease with increase in the irrigation interval. Thus, it was determined that irrigation at intervals of 1-2 days was appropriate for growing Pinus densiflora container seedlings.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.469-476
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• 1999

This study was carried out to investigate the growth and physiological response of shade intolerant and intermediate tree seedlings to enhanced UV-$B_{BE}$(biologically effective UV-B) radiation. The seedlings of Betula platyphylla var. japonica Hara(shade intolerant species) and Fraxinus rhynchophylla Hance(shade intermediate species) were treated with one of the three levels of UV-$B_{BE}$ dosages - ambient UV-$B_{BE}$, ambient+3.2, and ambient+$5.2\;KJ\;m^{-2}day^{-1}$) for 14 weeks in the field condition. Height and root collar diameter growth, leaf area, and biomass production of the seedlings of two species were reduced by enhanced UV-B radiation. Leaf stomatal resistance to water vapor of the F. rhynchophylla seedling was increased by the UV-B increment. The reductions in total chlorophyll and carotenoid were more apparent in the F. rhynchophylla than B. platyphylla seedling. There was no statistically significant changes in the concentration of UV-B absorbing compound($A_{300}$) in the leaves of the two species among the UV-B treatment. However the $A_{300}$ tented to be increased in F. rhynchophylla by enhanced UV-B radiation. These results indicate that the growth and the physiological and biochemical responses between B. platyphylla and F. rhynchophylla were different to enhanced UV-B environment.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.523-532
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• 1999

The studies were carried out to develop an urban forest aromatic bath in the idle space within city area for handicapped persons, patients and city workers, who having less chance to visit the natural forest aromatic bath. The environmental conditions were checked in the experimental double vinyl house where native and exotic aromatic woody and herbaceous plants were growing with minimum energy input in the periods of mid-winter and mid-summer. The growth and photoperiodic responses of the plants to the low and high temperatures were observed during winter and summer respectively. The most of herbaceous plants in the double vinyl house with the controlled minimum night temperature of $-2^{\circ}C$ had no winter injury but did not grow and started the growth in April. The exotic herbs such as Catnip faassen's(Nepeta x faassenia) and Lemon bergamot(Monarda citriodora) grew better in the longer photoperiodic conditions. The growth rates of Abies koreana, Thuja koraiensis and Pinus sylvestriformis in the early spring were affected mainly by the night minimum temperature and less affected by the photoperiodic conditions during winter. The native aromatic herbs such as Robdosia japonica, Molsa punctulata, Agastache rugosa and Codonopsis lanceolata showed stimulatory growth at the 16 hours day-length in case of the high temperature vinyl hose. The height and root collar diameter growth of pine seedlings were inhibited in maxim temperatures over $40^{\circ}C$ during summer.