• Journal of Environmental Health Sciences
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• v.37 no.2
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• pp.94-101
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• 2011

Objectives: The purpose of this study is to evaluate the noise exposures of firefighters according to their time-dependent activity patterns. Methods: Personal exposure levels were measured for six days and nights using noise dosimeters; three days and nights for on-duty tasks, the other days and nights for off-duty activities. Results: The total amount of time spent in the workplace was 13,677 min (67%), outside areas 4,833 min (23%), in transit 1,002 min (5%), and other indoor area 807 min (4%) during a working period. However, during off-days they spent 10,858 min (76%) at home, 1,382 min (10%) outdoors, 1,225 min (9%) other indoors, and 493 min (3%) in transit. As a result of individual exposure levels, TWA did not exceed 90 dBA of the occupational exposure limit for the majority of the firefighters, whereas the levels of Lmax were 119 dBA, which were higher than the noise levels of firefighters in USA. Sometimes during dispatching the levels of Lpeak exceeded the ACGIH exposure standard (140 dBC). The Leq levels in transit were higher than the levels in home and other indoors even though the activity time is short. Conclusions: This paper characterized the noise exposure patterns of firefighters in Korea. We suggest that special noise sources, including sirens and speaker phones, should be readjusted to reduce noise exposure.

• Journal of Aquaculture
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• v.12 no.4
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• pp.255-266
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• 1999

The early development, growth, and morphological changes of Tiger puffer Takifugu rubripes are described on the basis of a seres of a series of reared specimens. Detailed o수 the early developmental stages are illusrtated withe special reference to morphological transformation. Egg and sperm of puffer fish Takifugu rubripes were obtained from mature adults under natural conditions, ferilized artificially and incubated in the laboratory. The incubation period of fertilizd eggs was 160 to 180 hours at a temperature of $15.1~ 18.0^{\circ}C$. Larvae were fed successively with rotifer, Artemia nauplii and artificial food for 90 days. The mean total length of newly-hatched larvae was about 2.8mm. Mouth opening occurred on the 1- day yolk-sac larvae and initial feeding was observed on th 4-5 days after hatching . The morphological transitions from the larvae to juvenile and juvenile and juvenile to young stages occurred when fish reached about 10mm in total length(about 30 days after hatching) and about 32mm in total length(about 60days after hatching) , respectively. The coefficient of variation in total length distribution increased with growth. Following the appearance of its peak at the size of about 18mm in total length, the coefficient value declined. Many changes in proportion of the body parts to total length were observed at about 9~10mm and 30~33mm in total length, corresponding to the transformations from larvae to juvenile and from juvenile to young, respectively. Also one big morphological change was observed at about 18mm in total length that divide the juvenile stage into two sub-stages.

• Journal of Chest Surgery
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• v.27 no.3
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• pp.226-229
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• 1994

VATS is now used by many thoracic surgeons and in various anatomic locations such as lung parenchyme, pleura and mediastinum, etc. VATS of mediastinal masses has special characteristics compared to that of other diseases. Those are no positional changes of the mass during collapse of the lung and close proximity of the mass to major vascular structures, nerves and other vital organs. From 1992. July to 1993. August, 10 mediastinal masses were treated with video assisted thoracoscopy. There were five males and five females, ages ranged from 11 years to 65 years with average 37.7 17.7 years old. Of the 10 patients, 4 were bronchogenic cysts, 2 were teratoma, and the others were thymoma, neurilemmoma, pericardial cyst, and thymic cyst. Needle aspiration was done in large cysts and the working thoracotomy[or utility thoracotomy] was done in large solid masses for the purpose of easy dissection, easy handling and easy delivery of the mass. The average operation time were 155.6 6.8 minutes and the duration of air leakage were 1 2.2 days. The duration of the chest tube drainage were 3.3 2.6 days. The lengths of the postoperative hospitalization were 5.1 2.7 days which were shorter than those of 12 mediastinal masses treated with conventional thoracotomy during the same periods [p<0.05]. There was 1 patient converted to thoracotomy because of a bleeding at innominate vein. 3 postoperative complications were occured. Those were persistent air leakage for 7 days, diaphragmatic palsy and hoarseness which were recovered within 1 month. We conclude that mediastinal mass can be excised with video assisted thoracoscopy and the posthospitalization is reduced. But careful attention is required for avoiding injury to major vascular structures, nerves, and other vital organs.

• Applied Microscopy
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• v.29 no.2
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• pp.201-209
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• 1999

Remodeling of epithelial cells during wound healing in the skin of the Korean fire-bellied toad, Bombina orientalis, were examined using the scanning and transmission electron microscopical analyses. Artificial wounds were induced on the dorsal surface of the skin by excision, and reared in special cages with normal diets for up to 31 days after injury. From 4 days after wounding, regenerated epithelial cells are more rapidly migrated to wounding area, and remodeling of tissue components are proceeded gradually. Especially, formation of basal lamina between regenerated epithelium and dermis, and reconstruction of cellular junctions such as desmosomes (among the regenerated epithelial cells) and hemidesmosomes (between basal epithelial cells and basal lamina) are detected through fine structural analysis from 10 days after injury. Parakeratosis of regenerated epithelial cells observed during 16 to 19 days after wounding.

• Development and Reproduction
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• v.10 no.3
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• pp.193-196
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• 2006

The process in the formation of primordial germ cells, primitive and early gonadogenesis were investigated by histological examination for the reproductive physiological study in the scorpion fish, Sebastiscus marmoratus. The primordial germ cells about $10\;{\mu}m$ in diameter were observed in the fibrous mesenchymal tissue located between gut and mesonephric duct of the larvae within the maternal body. As the fibrous epithelium extends to the direction of peritoneum, the primordial germ cells moved. From 31 days post parturition, the fibrous epithelium gets thicker, and the primitive gonad starts to form. From 49 days post parturition, as the primitive gonad of the primitive gonad extend, it starts to form cavity, and about 60 days post parturition, the formation of the ovarian cavity is completed. From 79 days post parturition, germ cells proliferated along the inner edge of the ovarian cavity.

• Korean Journal of Plant Resources
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• v.20 no.5
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• pp.461-465
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• 2007

In this study, changes in the overall antioxidant properties and chemical constituents including total phenolics and vitamin C of R. occidentalis fruit during ripening are studied. The antioxidant activity was measured by the free-radical scavenging activity(DPPH method) and reducing power(potassium ferricyanide method). Although, the weight and diameter of R. occidentalis fruit were increased with the progress of ripening, antioxidant activity and total phenolics were decrease during ripening. The highest free-radical scavenging activity(at $125{\mu}g/m{\ell}$) and reducing power(at $100{\mu}g/m{\ell}$) in fruit were 61.67% and 0.71, respectively. Total phenolic content and vitamin C content in fruit of 5 days after fruit set were $220.73{\mu}g/g$ and $540.45{\mu}g/g$, respectively. A linear correlation(r=0.9761) was shown between free-radical scavenging activity and total phenolic content.

• The Korean Journal of Nuclear Medicine Technology
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• v.21 no.2
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• pp.49-54
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• 2017

Purpose The high-dose administration of I-131 has been standing for the basic therapy method of thyroid cancer. In korea, it is not necessary for patients to be hospitalized if the administration dose are under 1.2 GBq. However, if the dose are over 1.2 GBq, the patients should be stay in special ward with radiation shield. In such cases, the radioactivity level upon release should be under a dose of $70{\mu}Sv/hr$ at a distance of approx. 1m. This regulation bring the patients to stay for about 2 to 3 days in ward before the release. Materials and Methods Using the inpatients' release data of severance hospital, an inpatient-days were retrospectively calculated and compared with practical data and estimate the inpatient-days with the conditions of korea ($70{\mu}Sv/hr$), Japan ($30{\mu}Sv/hr$), germany ($3.5{\mu}Sv/hr$ at a distance of approx. 2 m), and other european countries. Results When a effective half-life of 15.4 was used, the expected inpatient-days were calculated as 2.15 days in the condition of Japanese regulation and 1.37 days in the condition of korean regulation. The practical inpatient-days of patients in Severance hospital were 1.32 days. Conclusion As ICRP 94 has been mentioned that the release of patients administrated with I-131 for the therapy should be carefully considered because each patients has different thyroid uptake rate and their conditions with family members after the release from the ward. Nonetheless, efforts to bring more aquate data which is for getting closer to the practical data should be continuously studied.

• Korean Journal of Poultry Science
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• v.8 no.2
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• pp.77-89
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• 1981

The experimental study was undertaken to confirm the effect of vaccination of birds with Newcastle disease (ND) vaccines on the Market by use of th. various vaccination programs. Sixteen groups of birds varying from 2 to f days of age, which were originated from hyper-immunised hens against ND were immunised by three different ways, a live vaccine only, a killed vaccine only, and the combination of a live and killed vaccine according to the each schedule of employed programs. In the administration of a live vaccine only, birds were immunized by one of following methods, the combination of intranasal and intraocular inoculation, intramuscular inoculation, via drinking water and the double inoculation by spray and drinking water application. Except for the double application, all the birds were vaccinated 2,3 or 4 times with two volumes of the virus dose (drinking water application) instructed by the commercial vaccine laboratory, until 21, 28 or 30 days of age, and all the immunized birds 19, 21 or 28 days postvaccination were challenged intramuscularly with 1.0$m\ell$ of 10,000 MLD per $m\ell$ of a virulent ND virus. In the administration of the combination of a live and killed vaccine, birds were immunized 2 or 3 times intranasally at first until 14 or 28 days of age with the same dose of the above experiment of a live vaccine, and then inoculated intramuscularly 1 or 2 times until 60 days of age with 1.0 $m\ell$ of a killed vaccine. And all immunized birds 11 days postvaccination were challenged with the same procedure of the above experiment. In the administration of a killed vaccine only, birds were immunized 3 times intramuscularly until 28 days of age with varied dose (0.2-0.5 $m\ell$) of a killed vaccine and all immunized birds 33 days postvaccination were challenged with the same procedure of the above experiment. The results obtained are summerised as follows: All birds vaccinated by using the combination of a live and killed vaccine program or a killed vaccin only appeared to be refractory. without any sign of illness, to the challenge exposure with 1.0$m\ell$ of 10,000 MLD per $m\ell$ of a virulent ND virus. On the other hand, the survival rates of birds of live vaccine groups immunized by a number of vaccine program such as Salsbury's day old program, 3-3-3 program, the Institute of Veterinary Reserch program and Multiple inoculation program, were 39.58%, 43.7%, 43.75% and 47.80%, respectively. And the survival rates of birds vaccinated with a live vaccine by 4 different ways of administration, i.e., double inoculation by water and aerosol application, intramuscular injection, intranasal instillation and via 4.inking water were 87.50%, 64.06%, 42.18% and 25.00%, respectively.

• Journal of the Korea society of information convergence
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• v.1 no.1
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• pp.47-54
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• 2008

This study analyzed the status and causes for the dropouts of college based on the survey conducted among 14,210 freshmen attending D College, other than the supernumerary special selection, from 2001 through 2005. A significant difference was shown in all items of general characteristics. The dropout rate of women, generally selected and general highschool graduated were higher than for men, specially selected and special high school graduated, respectively. The most dropouts were due to Not Return(40.16%), followed by Unenrolled(32.98%), Voluntary Leave(26.05%) and Expelled(0.81%) in order. In the distribution of the central tendency values measured from the entire subjects, the high school records and the days of absence showed a positive skewness, while the college records showed a negative skewness with the data mostly around a higher grade. The standard deviation indicating that the dropouts got the scores higher than those of the continuing students demonstrated that there was relatively insignificant difference in scores between two groups. It was demonstrated that both the high school records and the days of absence affected the dropout. The lower the high school records were, and the more the days of absence were, the more influence both items had on the dropout. The influence degree of each item was similar. Lower the scores were in terms other than the first term in the freshmen year, the more influence it had on the dropout. The most dropouts were influenced by the scores of the freshmen year, followed by the credits of the second term, the scores of the first term, the scores of the second term, and the credits of the first term in the freshmen year. Among the general characteristic items, the most dropouts were influenced by the course of study, followed by the gender. The effect of other items was insignificant.

• Korean Journal of Microbiology
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• v.12 no.4
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• pp.159-179
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• 1974

In order to investigate morphological and cultural characteristics of strains in species, Flammulina velutipes, the author collected isolates of Flammultina velutipes at 49 locations in Korea and cultivated these isolates on the various kinds of solid media. After investigating the cultural characteristics, appeared on the various media, he obtained the following results : 1. The variation of colors in the fruit bodies is connected with the variation of climatic environments(composite effects between mean temperature in January and number of rain days of 1mm and over precipitation). The author, therfore, can find out the trend that brown type is distributed in the midland climatic region and yellow type in the southern climatic regoin. 2. Two types can be classified into several strains respectively : the strain of abundant or insufficient productivity, and strain of selectivity or non-selectivity of media. 3. According to the results of mutual comparison of soluble mycelial proteins by disc electrophoresis using polyacrylamide gels, each type has special common protein fractions(brown type : band located at 26..5mm position from surface of gel, yellow type : band located at 24.5mm position from surface of gel), and each strain has special protein fractions too. Therefore this phenomenon seems to support the results obtained by the above-stated morphological and cultural studies. 4. In the adaptability of strains to the temperature, every strain has the nature of growing in lower temperature(the optimum temperature of 20.deg.C to 25.deg.C) except that YI-1 strain has the optimum temperatue of $25^{\circ}C$-26^{\circ}C. And mycelial growth of every strain is discontinued at $35^{\circ}C.$ 5. In the adaptability of strains to the H-ion concentration, every strain has wide adaptable range of H-ion concentration, and has optimum range of pH 5.5 to 6.6 in mycelial growth excepting YA01, BI-2 and YI-1. 6. In the utility of carbon sources, the mycelial growth of every strain is very poor on the media containing xylose(average diameter of mycelial growth : 18mm), and most strains utilize favorably sucrose(39mm), maltose(37mm) and dextrose(35mm) in mycelial growth. In the utility of nitrogen sources, every strain utilizes favorably organic nitrogens(36 mm)more than inorganic nitrogens (25 mm), and utilizes fully peptone nad asparagine in organic nitrogens. Especially BA-1, BIK-2 and YA-1 strains grow vigorously on each media containing various carbon and nitrogen sources. 7. The characteristic tests of the number of days required for mycelial growth, the number of days requried for sprout of young bodies, the length of stipe and the number of fruit bodies formation seem to be useful methods in the early selection of the strain of the abundant productivity.