• Korean journal of applied entomology
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• v.41 no.3
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• pp.225-231
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• 2002

The entomopathogenic nematodes, Steinernema carpocapsae All strain (ScA), S.glaseri NC strain (SgN) and H. bacteriophora NC 1 strain (HbN), were evaluated for the effects on egg mass formation by the northern root-knot nematode, Meloidogyne hapla in pot experiment using tomato. In the first experiment, 2.5$\times$10$^{5}$ infective juveniles (Ijs) of entomopathogenic nematodes were inoculated to 100 g of the soil infected with ca. 450 Ijs of M. hapla/100 ㎤ in 150 $mell$ container. The number of egg mass was significantly decreased to 9.4-36.5 in ScA, to 5.7-24.7 in SgN and to 11.2-16.0 in HbN treatments compared with 62.5 in M.hapla alone. In the second experiment, ScA and S.carpocapsae Pocheon strain (ScP) and SgN and S.glaseri Dongrae strain (SgD) were treated to 350 g of the soil infected with 100, 200 M.hapla larvae/100 ㎤ in 450 $mell$ container The entomopathogenic nematodes were inoculated at the rate of 2,020 Ijs and 1.6$\times$105 Ijs in 350 g soil. The number of egg mass of M.hapla were significantly decreased in the entomopathogenic nematode treatments compared with M.hapla alone although no differences were observed among Steinernema species, strains, or infection concentrations. Treatments of entomopathogenic nematodes 3 days before M.hapla inoculation were more effective on reduction of egg mass formation than those of 3 days after M.hapla treatments. Growth of tomato was not affected by entomopathogenic nematode treatments.

• Journal of Life Science
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• v.20 no.2
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• pp.245-252
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• 2010

The purpose of this study was to investigate the effects of aerobic exercise and Allium tuberosum intake on blood lipids, MDA and antioxidant enzyme in rats. Twenty four male Sprague-Dawley rats, 4 weeks old, were used. Experimental groups were aerobic exercise with Allium tuberosum intake group (A, n=6), aerobic exercise group (B, n=6), Allium tuberosum intake group (C, n=6), and the control group (D, n=6). Aerobic exercise was administered through a treadmill running program (14~15 m/min, $0^{\circ}$ grade, 25~30 min/day, 5 day/wk) and these rats were given 5% Allium tuberosum for 2 wk. The results of this study are as follows: TC and TG didn't show change; groups A, B, C showed a significant increase in HDL-C compared to the D group; groups A, B, and C showed a significant decrease in LDL-C compared to the D group; groups B and C showed a significant decrease in MDA level compared to the D group; groups B and C showed a significant increase in SOD activity compared to the D group; and the A group showed a significant increase in CAT activity compared to the D group. In conclusion, low intensity aerobic exercise and intake of the natural antioxidant Allium tuberosum seem to have the health promoting effect of retarding oxidative stress by decreasing lipid peroxidation.

• Journal of Korean Society of Forest Science
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• v.9 no.1
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• pp.49-54
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• 1969

As one phase of the biological control of the Pine gall-midge, Thecodiplosis japonensis Uchida et Inouye, this investigation on birds as a vertebrte predator of the larvae of Pine gall-midge was carried out. Species of the birds as predator, number of the larvae as prey for individual birds and seasonal trends of the prey quantity were studied. This work was carried out during the late fall of 1967 and 1968 at Kwang Nueng Forest which is one of the heavily infested districts by the Pine gall-midge. 1. Korean Great-Tit, East China Marsh-Tit, Quelpart Coal-Tit, White-headed Long-tailed Tit, Varied Tit, Kamchatkan Rustic Bunting, Yellow-thrated Bunting, Chestnut Bunting and Korean Goldcrest were found to be the predator of the larvae of Pine gall-midge. 2. The average number of larvae as prey found from individual predator bird species were approximatly 108 for Kamchatkan Rustic Bunting, 17-64 for East China Marsh-Tit, 25-28 for Korean Great Tit and 36 for Quelpart Coal Tit. 3. The seasonal change in the number of the larvae which fell into the ground affected the seasonal trends of the prey quantity of the predator birds 4. Among the 380 birds examined, 157 birds were found to attack the larvae of Pine gall-midge.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.81-86
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• 2009

Economic injury level and control thresholds for the management of beet army worm, Spodoptera exigua (Lepidoptera: Noctuidae) were evaluated on chinese cabbage of two different planting time. Two inoculation times were tested for each planting and the number of inoculated larva was 10, 20, 40, 80, respectively. Damages of leaves by first inoculation were 63.2% after eight days planting on 80 larva inoculation plot. By the second inoculation, those were below 50% after 20 days planting on the end of September. The linear relationships between population density and yield reduction were as following; Y = -10.62x + 867.9 ($R^2\;=\;0.643$) for 5 days and Y=-6.432x + 1074 ($R^2\;=\;0.720$) for 20 days. Based on these results the economic injury level was 5.4 larva for five days and 9.0 larva for 20 days per 20 chinese cabbage. The control thresholds calculated by 80% level of economic injury level were 4.3 and 7.2 larva, respectively.

• Parasites, Hosts and Diseases
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• v.32 no.4
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• pp.223-230
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• 1994

Clonorchiasis is an important parasitic disease of humans in Korea. The present study intended to compare sonographic findings with histopathological changes in experimental clonorchiasis. Eighteen New Zealand white rabbits were infected with metacercariae of Cknorchis sinensis, and examined 4, 10, and 22 weeks post-infection (PI). Four infected rabbits were treated with praziquantel 10 weeks PI and were examined 12 weeks after treatment. Sonography revealed mild to severe dilatation of the intrahepatic ducts (IHDD) and slightly increased periductal echoes in 12 out of 14 rabbits at 4 weeks PI, and all of the animals after 10 and 22 weeks PI and 12 weeks after treatment. The histopathological lesions were duct dilatation, mucosal hyperplasia, and periductal fibrosis, which progressed from 4 weeks to 22 weeks PI and even in treated rabbits. The dilated intrahepatic ducts over 1 mm diameter were detected by sonography. The present results indicate that sonographic findings are well correlated with histopathological lesions in rabbit clonorchiasis except for early phase of light burden of infection. The sonography has a limitation in discriminating residual sequelae of the ducts after praziquantel treatment.

• Korean journal of applied entomology
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• v.45 no.3 s.144
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• pp.317-325
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• 2006

According to the preceding survey on insect pests of the green perilla, Perilla frutescens var. japonica HARA, The major pests were Aphis egomae Shinji, Pyrausta panopealis (Walker), Tetranychus urticae Koch, Polyphagotarsonemus lotus Banks, Tetranychus kanzawai Kishida at Guemsan, Chungnam, 2004. Aphis egomae causes nearly 100% injury of the green perilla in uncontrolled green houses. A field study was conducted to estimate economic injury levels (EILs) and control thresholds (CTs) for A. egomae injuring green perilla in green houses. Different densities of A. egomae ranged from 1 to 80 aphids per 100 plants in early inoculation. The mean injurying rate of plant was 2.4% to 40.5% at the end of June at differently inoculated levels. The economic loss time calculated by the ratio of cost managing aphid to market price (C/V) (C: cost managing aphid, V: Market price) in early season (from May to 13. June) was 5.8% and in peak season (from 13. June to 30. June) was 9.3%. Economic injury level in early and peak season was 5.3 aphids per plant and economic injury levels in peak season were 0.6 aphids per plant and 7.6% injured rate of plant. The control thresholds calculated by 80% level of economic injury level in peak season were 0.5aphids per plant and 6.1% injury rate of plant, respectively.

• Parasites, Hosts and Diseases
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• v.22 no.2
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• pp.229-237
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• 1984

The migration and distribution pattern of spargana in mouse body was observed after experimental infection through mouth. The spargana were obtained from the snake, Natris tigrina lateralis, caught in Hoengseong-gun, Kangwon-do. A total of 28 male mice (ICR strain), 21∼259 in body weight, were fed each with 5 scolices (and necks) of spargana and killed after 10 minutes to 14 days. Systemic autopsy was performed on each mouse to recover the spargana. The results are as follows: 1. The spargana were found to penetrate into the stomach or duodenal wall of mice as early as 10 minutes after infection. They completed the penetration within 30 minutes and appeared in abdominal cavity. It was observed that spargana did not migrate tangentially along the gut wall but directly perforated the wall. 2. After 1 hour to 1 day the majority of spargana distributed in abdominal cavity of mice except a few which migrated to muscles or subcutaneous tissues. 3. It was within 7 days that nearly all of the spargana migrated to subcutaneous tissues. Out of total 28 in number found from subcutaneous tissues, 13 distributed around neck region, 12 around trunk and other 3 on head of mice and the most common sites were submandibular and subscapular areas. There was nearly no host tissue reaction to migrating spargana. 4. The initial length of spargana given was 4 mm in average but it increased to 12 mm after 7 days and to 35 mm after 14 days. The results suggest that spargana orally given to mice penetrate the gut wall within 30 minutes followed by escaping into abdominal cavity, and after passing through thoracic cavity or abdominal wall they anally Localize in subcutaneous tissues chieay around neck region within 7 days.

• Journal of Aquaculture
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• v.16 no.1
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• pp.24-30
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• 2003

Studies of the seed production of Urechis unicinctus were conducted under the laboratory conditions to obtain some information for the U.unicinitus culture. The experiment included developmental studies of the egg development, larval culture, sediment preference and growth of young U.unicinctus. The experiment were conducted from March to August, 2000. The adults of U.unicinctus collected in Namhae-do, Korea. The developments of the fertilized eggs were observed under a light-microscope at intervals of one hour after containing with density of one individual per 1 $m\ell$. The larvae were fed with Phaeodactylum tricornutum cultured at the laboratory. The concentration of the phytoplankton for the feed was 30,000 cells per individual larva. With progress of development, the food concentration was gradually increased, up to 10,000 cells per individual for the young U.unicinctus. Trochophore larvae appeared on the 68 hours after hatching. On the 32 days after hatching, over 50% of fertilized eggs developed into young U.unicinctus. In order to investigate the effect of sediment on the growth and burrowing of U.unicinctus, the young worms were reared in tanks with different grain sizes. The highest value of sediment preference and survival rate of U.unicinctus was shown in the mixture sediment group with below 0.10 mm, 1.01∼12.00 mm, over 3.01 mm and shell. The lowest value in both sediment preference and survival rate of U.unicinctus was observed in 1.0l∼2.00 mm grain size.

• Journal of Bio-Environment Control
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• v.29 no.3
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• pp.293-305
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• 2020

This experiment was aimed to identify concentrations of mineral nutrients in leaf lettuce (Lactuca sativa) grown on hydroball aquaponics and in the water for growing fish by conducting two experiments. The experiment I (Expt. I) was conducted with 12 fishes (F12) with and without filter, hydroball and plants (H12 (12 fishes, hydroball), FHP12 (12 fishes, filter, hydroball, 6 plants) and HP12 (12 fishes, hydroball, 6 plants)), and the experiment II (Expt. II) was with and without plants (FH15 (15 fishes, filter, hydroball), FHP15 (15 fishes, filter, hydroball, 6 plants)). The pH level in the water of all the treatments was decreased during the growing period, and the pH and EC of the water were lower in all the treatment with plants than those without plants in both Expt. I and Expt. II. When compared with adequate nutrient concentrations for hydroponics, nitrate nitrogen (NO₃-N) and phosphorus (P) concentrations in the fish growing water were higher under the FHP15 treatment in Expt. II; however, potassium (K), calcium (Ca), and magnesium (Mg) were only 16, 49, and 82% of hydroponics, representatively, and iron (Fe) was not detected. The fresh weight of lettuce harvested from the FHP15 treatment was 38 g, only a 30% of marketable lettuce yield. The T-N and P contents of the leaf tissue grown under the FHP15 treatment were close to the optimal level; however, the K, Ca, and iron (Fe) contents were less than the optimal with no deficiency symptom.

• Journal of the Korean Applied Science and Technology
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• v.37 no.3
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• pp.409-417
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• 2020

The purpose of this study was to investigate the effects of different types of exercise training on ẞ-Amyloid, Brain-Derived Nerurotrophic Factor(BDNF) and cognitive function in mice with Diabetes Mellitus Group(DM.G). 24 male C57BL/6 mice were randomly assigned to the control (C.G. n = 6) and Diabetes Mellitus Group(DM.G. n = 18) groups. After the Diabetes Mellitus induction period, the DM group was subdivided into DM.G. + sedentary (DM.G., n = 6), DM.G. + endurance exercise (A.G, n = 6), and DM.G. + resistance exercise (R.G., n = 6). The A.G. and R.G performed treadmill and ladder climbing exercises 5 times per week for 8 weeks, respectively. After 8 weeks the results are as follows: ẞ-Amyloid showed higher levels of DM.G. than in A.G., R.G., and C.G., but was not statistically significant(p>.05). BDNF was significantly lower in DM.G. than in C.G., A.G., and R.G.(p <0.05). The Y-maze task performance for cognitive function was significantly lower in DM.G. than in C.G., A.G., and R.G.(p <0.05). These results predict that diabetes can negatively affect ẞ-Amyloid, BDNF and cognitive function. It can also be predicted that low-intensity exercise can positively improve ẞ-Amyloid, BDNF and cognitive function regardless of the type of exercise.