• Korean journal of applied entomology
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• v.4
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• pp.39-46
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• 1965

The author studied on the bionomics of Oriental moth. Cnidocampa flavescens WALKER, damaging to the persimmon tree n the southern part of Korea from 1964 to 1965. The results can be summarized as follows; 1. Emergence peak period of Oriental moth was mid-June in Taegu district and eggs are deposited on the opposite side of persimmon tree leaf. Specially most of eggs are deposited on the terminal part of opposite side and peak period s also mid-June. 2. Hatched Percentage of eggs was $84.4\%$ in 1964 while $96.1\%$ in 1965 at the rearing room. Mean egg Period was $5.984\pm0.162$ in 1964 while $6.262\pm0.094$ days in 1965. Thus during two years, the egg period was about 6 days. 3. In the growth ratio of Oriental moth fed on various host plants persimmon tree, Acer negund, Hazel-wood and Platanus, the best growth ratio was shown on the leaf of Hazel-wood from 1st till 3rd instar, but, on the contrary, persimmon tree was the best from 4th till the last instar. The growth ratio of head width was also the same tendency as the body length above mentioned. Individuals fed on the leaf of platanus were dead after 20 days. 4. Oriental moth has one generation a year and molts 6 times. The first molting occurred in 5 hours after hatched, and the other moltings were done at f days intervals. After 3 days since the last molting, larvae made the non for over-winter in it. 5. As the bristles on the process of larval body are different from each position and instar, judgement of instars are possible by the counting of bristles on the body according to the Table 8. Specially the bristle of L. 2., D. 2, 3 ,8. 10. and L. 1, 3, 4, 5, 6, 7, are perfectly different from each instar. From these bristles, instars can be recognized easily. 6. Pupation of larvae in the over-wintered cocoon on the stem of persimmon tree was done in mid-May and continued will early June when emergence will take place. 7. Mean number of eggs in the ovary was $1325.5\pm2.7182$

• 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.

• The Korean Journal of Nuclear Medicine
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• v.39 no.3
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• pp.174-181
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• 2005

Purpose: Reduction of respiratory motion artifacts in PET images was studied using respiratory-gated PET (RGPET) with moving phantom. Especially a method of generating simulated helical CT images from 4D-CT datasets was developed and applied to a respiratory specific RGPET images for more accurate attenuation correction. Materials and Methods: Using a motion phantom with periodicity of 6 seconds and linear motion amplitude of 26 mm, PET/CT (Discovery ST: GEMS) scans with and without respiratory gating were obtained for one syringe and two vials with each volume of 3, 10, and 30 ml respectively. RPM (Real-Time Position Management, Varian) was used for tracking motion during PET/CT scanning. Ten datasets of RGPET and 4D-CT corresponding to every 10% phase intervals were acquired. from the positions, sizes, and uptake values of each subject on the resultant phase specific PET and CT datasets, the correlations between motion artifacts in PET and CT images and the size of motion relative to the size of subject were analyzed. Results: The center positions of three vials in RGPET and 4D-CT agree well with the actual position within the estimated error. However, volumes of subjects in non-gated PET images increase proportional to relative motion size and were overestimated as much as 250% when the motion amplitude was increased two times larger than the size of the subject. On the contrary, the corresponding maximal uptake value was reduced to about 50%. Conclusion: RGPET is demonstrated to remove respiratory motion artifacts in PET imaging, and moreover, more precise image fusion and more accurate attenuation correction is possible by combining with 4D-CT.

• Applied Biological Chemistry
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• v.13 no.3
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• pp.219-222
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• 1970

Riboflavin in the various materials which used for Takju brewing was determined and its quantitative changes in the Takju mashes which were mashed with polished rice and wheat flour respectively using Nuruk only for enzyme source, and with wheat flour and corn powder respectively using Nuruk and Koji, were checked at 24 hours intervals during the whole brewing period. The results obtained were as follows. a) The riboflavin contents in 100 grams of each materials were: Polished rice $46.9{\gamma}$ Wheat flour $67.3{\gamma}$ Corn powder $73.9{\gamma}$ Nuruk $169.0{\gamma}$ Koji of wheat flour $87.1{\gamma}$ Koji of corn powder $84.4{\gamma}$ b) About 30 to 40 percent of riboflavin in the polished rice, wheat flour and corn powder were losed by steaming at 10 pounds for 50 minutes. c) Riboflavin content in the plots used Nuruk only was decreased during 3 days after mashing and then increased markedly after 5 days and, more or less, decreased after 6 days. Quantitative changes of riboflavin in the plots used Nuruk and Koji showed a rugged curve without decreasing in early stages, and its content was also increased markedly 5 days after mashing and then decreased a little after 6 days. d) Approximately $82{\gamma}$ of riboflavin was determined in 100ml. of the ripened mash of the rice plot and $72{\gamma}$ in the wheat flour plot in the case of using Nuruk only. $88.6{\gamma}$ of riboflavin were determined in 100ml. of the ripened mash of the wheat flour plot and $83.6{\gamma}$ in the corn powder plot in the case of using Nuruk and Koji. e) It was assumed that $28.8{\gamma}$ to $41{\gamma}$ of riboflavin were contained in 100 ml. of finished Takju of the two plots used Nuruk only and 33.6 to 44.5${\gamma}$ in the both two plots used Nuruk and Koji. f) About $47.3{\gamma}$ of riboflavin were determined in 100 grams of Takju cake of the rice plot and $66.2{\gamma}$ in the wheat flour plot used Nuruk only, and $62.9{\gamma}$ in the corn powder plot and $64.5{\gamma}$ in the wheat flour plot used Nuruk and Koji.

• Journal of the Mineralogical Society of Korea
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• v.19 no.4 s.50
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• pp.277-289
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• 2006

This study was carried out to find a new material having high removal efficiency for the harmful red tide. C. polykrikoides grow very fast and accumulate into dense and visible patches near the surface of the seawater ('Water bloom'). Some mineral medicines and Hwangto (reddish soil consist of clay minerals and Fe-oxides) were used in this study to remove C. polykrikoides. The pre-determined sprinkling ratio of mineral vs. seawater which contains approximately 5,000 cells/mL of C. polykrikoides was 10 g/L. In order to quantify the removal efficiency, the density of living cells was measured by counting with the Intervals of 0, 10, 30, and 60 minutes after sprinkling. Five Hwangtos feom different localities were examined in this study. It is found that a material with a high concentration of Fe and Al was the most effective to remove C. polykrikoides. After the sprinkling of the Hwangto showing the best removal efficiency in the test, 99% of total algaes were found to be eliminated within 60 minutes. Jeokeokji showed the highest removal efficiency among clay mineral medicines(92% removal efficiency after 60 minutes), and the rests in decreasing order are as follows: Gamto (91%) > Baekseokji (89%) > Hydromica (81%). In addition, Fe-oxide mineral medicine similarly looking as fine-grained earthy Daejaseok showed 100% removal efficiencyafter 30 minutes, and Wooyoeryang, 95% after 60 minutes. It is noted that even little addition (1 g/L) of Daejaseok, 10% of Hwangto concentration into seawater showed the removal efficiency of 100% after 60 minutes. From the results, it could be concluded that the fine-grained earthy Daejaseok was the most effective natural mineral medicine to remove the C. polykrikoides from seawater. Under the microscope the removal mechanism was found to be activated in the following order: adsorption, swelling of chain colony, chain colony crisis and algaecide.

• Applied Biological Chemistry
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• v.13 no.1
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• pp.105-109
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• 1970

Thiamin in the various materials which used for Takja braving was determined and its quantitative changes in the Takju mashes which were mashed with polished rice and wheat flour respectively using Nuruk only for the enzyme source, and with wheat flour and corn powder respectively using Nuruk and Koji, were checked at 24 hours intervals during the whole brewing period. The results obtained were as follows. a) The thiamin contents in 100 grams of each materials were: Polished rice 107.8${\gamma}$ Wheat Pour 185.0${\gamma}$ Corn powder 410.2${\gamma}$ Nuruk 347.4${\gamma}$ Koji of wheat flour 170.1${\gamma}$ Koji of corn powder 257.3${\gamma}$ b) About 40 to 50 percent of thiamin in the polished rice, wheat flour and, corn powder were losed by steaming at 10 wounds for 50 minutes. c) The quantitative changes of thiamin in the Takju meshes showed a similar tendency. Thiamin contents were decreased markedly during 2 days after mashing but thereafter, almost unchanged till the mashes were ripened. Its decreasing rates in tile two plots uses Nuruk and Koji wereless thaw those in the two plots used Nuruk only. d) Approximately 6${\gamma}$ of thiamin was determined in 100 ml. of the ripened mash of the rice plot and 7.5${\gamma}$ in tire whet flour plot in the case of using Nuruk only. 12.4${\gamma}$ of thiamin was determined in 100 ml. of the ripened mash of the wheat flour plot and 15.4${\gamma}$in the corn powder plot in the case of using Nuruk and Koji. e) It was assumed that 2.4 to 3.5${\gamma}$ of thiamin were contained in 100 ml. of finished Takju of the two plots used Nuruk only and 5 to 7${\gamma}$ in the two plots used Nuruk and Koji. f) About 43.7${\gamma}$ of thiamin were determined in 100 grams of Takju cake of the rice plot and 56.1${\gamma}$ in the wheat flour plat used Nuruk only, and 81.4${\gamma}$ in the corn powder plot and 57.7${\gamma}$ in the wheat flour plot used Nuruk and Koji.

• Journal of Chest Surgery
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• v.39 no.4 s.261
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• pp.261-268
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• 2006

Background: Current vascular prostheses are still inadequate for reconstruction of small-diameter vessels. Autologous pericardium can be a good alternative for this purpose as it already possesses good blood compatibility and shows a mechanical behavior similar to that of natural arteries. However, the clinical use of autologous pericardial tissue as a small-diameter vascular graft has limitations due to mixed outcomes from uncertain biological behavior and difficulty to gain reliable patency results in animal experiments. To study this issue, we implanted fresh and glutaraldehyde-treated autologous pericardium as small-diameter arterial grafts in dogs, and compared their time-related changes histologically. Material and Method: As a form of 5mm-diameter arterial graft, one pair of autologous pericardial tissue was used for comparison between the glutaraldehyde-treated and the glutaraldehyde-untreated grafts in the bilateral carotid arteries in the same dog. The patency of the grafts were evaluated at regular intervals with Doppler ultrasonography. After the predetermined periods of 3 days, 2 weeks, 1 month, 3 months and 6 months, the grafts in each animal were explanted. The retrieved grafts were processed for light and electron microscopic analyses following gross observation. Result: Of 7 animals, 2 were excluded from the study because one died postoperatively due to bleeding and the other was documented as one side of the grafts being obstructed. All 10 grafts in the remaining 5 dogs were patent. Grossly, a variable degree of thromboses were observed in the luminal surfaces of the grafts at 3 days and 2 weeks, despite good patency. Pseudointimal smooth blood-contacting surfaces were developed in the grafts at f month and later. By light microscopy, mesothelial cell layers of the pericardial tissue were absent in all explanted grafts. Newly formed endothelial cell layers on the blood-contacting surface were observed in both the glutaraldehyde-treated and fresh grafts at 3 months and later. The collagen fibers became degraded by fragmentation in the fresh graft at 1 month and In the glutaraldehyde-treated graft at 3 months. At 6 months, the collagen layers were no longer visible in either the glutaraldehyde-treated or fresh grafts. By electron microscopy, a greater amount of coarse fibrin fibers were observed in the fresh grafts than in the glutaraldehyde-treated grafts and, more compact and well-arrayed layers were observed in the glutaraldehyde-treated grafts than in the fresh grafts. Conclusion: The glutaraldehyde-treated small-diameter pericardial arterial grafts showed a better endothelialization of the blood-contacting surface and a slower fragmentation of the collagen layers than the fresh grafts, although it has yet to be proven whether these differences are so significant as to affect the patency results between the groups.