• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.4
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• pp.812-816
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• 2001

In this paper we designed a dual-frequency circular sector microstrip antenna fed microstrip line with orthogonal polarization. The operating frequencies and polarization characteristics of the proposed antenna is calculated by using a cavity model. The antenna operating at about 1.87 GHz and 2.42 GHz is fabricated and its S-parameters and radiation patterns are measured.

• 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 Sericultural and Entomological Science
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• v.27 no.2
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• pp.20-27
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• 1985

This study was carried out to investigate the histological changes after the infection of nuclear and cytoplasmic polyhedrosis viruses(NPV, CPV) and the resistance to the viruses in various varieties of the silkworm fed on artificial diet. The results obtained were as follows; Among four varieties of silkworm tested, Jam 107$\times$Jam 108 was more resistant than the other varieties tested and Jam 119$\times$Jam 120 was the most resistant to CPV. In case of peroral infection with NPV, Jam 107$\times$Jam 108 showed lower mortality than the remained varieties in low concentration (104/ml). However, all varieties showed high mortality as the concentration of viruses was increased. With infection of CPV, the varieties showed high mortality at the concentration of 107 and 108/ml, while Jam 119$\times$Jam 120 showed the lowest mortality at virus concentration of 104/ml. The fat bodies, epidermal cells and tracheal epithelial cells showed high susceptibility to NPV to break the cells completely and liberate the debris to the body cavity. The CPV infected only the cylindrical cells of mid-gut and formed polyhedrons. In some cells, CPV was liberated to gastral cavity. In the electrophoretic pattern of hemolymph protein of silkworm larvae infected with NPV, bands were dimmed and disappeared as symptom aggravated after infection. Electrophoretic pattern of homolymph proteins of silkworm larvae infected with CPV showed no numerical difference at the later stage of infection, and one or two bands was observed along with lowering the concentrations.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.7
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• pp.167-173
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• 2001

The simulated die-casting process in which the traditional plaster casting process is combined with Rapid Prototyping technology is being used to produce AI, Mg, and Zn die-casting prototypes. Unlike in the die-casting process, molten metal in the conventional plaster casting process is fed via a gravity pour into a mold and the mold does not cool as quickly as a die-casting mold. The plaster castings have much larger and grosser grain structure as compared with the normal die-castings and the thin walls of the plaster mold cavity may not be completely filled. Because of lower mechanical properties induced by the large grain structure and incomplete filling, the conventional plaster casting process is not suitable for the trial die-casting process to obtain quality prototypes. In this work, an enhanced trial die-casting process has been developed in which molten metal in the plaster mold cavity is vibrated and pressurized simultaneously. Patterns for the casting are made by Rapid Prototyping technologies and then plaster molds, which have a runner system, are made using these patterns. Pressurized vibration to imparted molten metal has made grain structure of castings much finer and improved fluidity of the molten enough to obtain complete filling at thin walls which may not be filled in the conventional plaster casting process..

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.7
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• pp.998-1009
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• 1999

In this paper, a microstrip aperture-patch antenna and a microstrip ring antenna, which have single microstrip line feeding systems for the circular polarization, are designed, and experimental results are presented at X-band. The microstrip aperture-patch antenna is characterized by its wide operating frequency range, and the microstrip ring antenna is suitable for a basic radiator in the large array antenna due to its small size. Several design parameters for these antennas are considered and analyzed to improve antenna characteristics such as VSWR bandwidth and axial ratio. Initially, the sizes of the aperture and ring radiator are determined on a basis of the cavity model, then shapes of the patch within the aperture and the inner stub of the ring are optimized using Ensemble software. Measurement results show that the aperture-patch antenna has 25% of VSWR bandwidth and 1.2dB of axial ratio at the boresight, and the ring antenna has 6.7% of VSWR bandwidth and 1.6dB of axial ratio at the boresight.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.3
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• pp.469-474
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• 2004

The objective of the current study was to determine the effects of arabinoxylane and polysaccharide peptide (PSP) on the immune cell functions. Both arabinoxylane and PSP increased plaque forming cell (10-15%) and rosette forming cell (10-30%) formation. Stimulation of macrophage with PSP (18%) and arabinoxylane (22%) resulted in increased phagocytic effects. Both arabinoxylane and PSP induced the tumor suppressive effect in mice injected sarcoma-180 cell intracutaneously. When the mice injected intraperitoneal cavity with sarcoma 180 cells, survival ratio was increased in the mice fed on arabinoxylane and PSP. The ratio of PCA was slightly decreased in the mice fed on PSP, especially fed on arabinoxylane than in the control mice. The concentrations of blood histamine were slightly decreased in the mice fed on arabinoxylane and PSP. These results suggest that the capacity of arabinoxylane and PSP seems to act as a potent immunomodulator causing augmentation of immune cell activity, and with the absence of notable side-effects, arabinoxylane and PSP could be used as a biological response modifier having possible therapeutic effects against immunological disorders.

• Journal of fish pathology
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• v.16 no.1
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• pp.13-21
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• 2003

The infection characteristics with scuticociliates at on-land rearing farms and hatcheries of flounder, Paralithys olivaceus was investigated during the year of 2001 by juvenile infection routes. When culture tanks for living food organisms such as chlorella, rotifer, and Artemia were searched, scuticocilates were detected both in live and dead rotifer, and at the dregs of culture tank bottoms at almost hatcheries. When rotifer infected with scuticocilates fed on fish larvae, lots of scuticocilate were inhabited at the bottom of fry rearing tanks. After feeding on scuticocilates-infected rotifer on fish larvae, first infection was detected at 10 days after bottom dwelling or 40 days old after hatching. By histopathological examination we confirmed the infection route of eyeball or brain contamination was that the ciliate worms digged through mouth and front part of the dosal fin cuticle, transferred into eyeball along the epithelium and muscle tissue, and reached finally into brain by the muscle and nerve tissue. The infection of internal organs was clarified into two routes. The first route was started from the infection at ventral and anal fin rays by the worms, and reached at the anus and rectum through the epithelium and muscle tissue. The second route was initiated from the infection at urinary organ and reached into the rectum epithelium cells, inner wall of intestine, abdominal cavity, pancreas, kidney, and pancreas. At seed production farms where fish larvae fed on scuticocilate-free rotifer, the worms were not detected not only at the food organisms culture tanks and juvenile rearing tanks but also larval flounder less than 7cm in total length.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.2
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• pp.245-251
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• 2006

The aim of this study was to investigate the effects of caponization on the bone characteristics, biomechanical property and histology in Taiwan country chickens fed to market age of 26 wks. Male Taiwan country chickens $D{\times}L_2$ were caponized or sham-operated at 8 wks of age, and selected healthy sham-operated and completely caponized chickens (prominent degenerated comb) were selected at 16 wks old and fed to 26 wks old for the trials. Fifteen intact male chickens (Intact), sham-operated chickens (Sham) and caponized chickens (Capon) were assigned for trial 1, and sixteen Intact and Capon were assigned for trial 2. Results in trial 1 showed that the abdominal fat and relative abdominal fat weights of Capon were significantly heavier than Intact and Sham (p<0.05), while the tibia weight and relative weight were the lightest (p<0.05). The tibia breaking strength, bending moment and stress of Capon were the poorest among groups (p<0.05). The trial 2 produced the similar observation that Capon were significantly lighter than Intact (p<0.05) in the tibia weight, relative tibia weight and their biomechanical properties. On histological determinations, Capon showed a thinner cartilage end and fewer chondrocytes (about 50%) and trabecular, and bigger marrow cavity; while decreased hemopoietic cells number with increased adipocytes than Intact observed by H&E stain and at low magnification. At high magnification, Capon showed a decrease in the chondrocyte size by 33 to 50%, with smaller nucleus located near the cell membrane, and exhibited monocellular form chondrocytes. Capon also showed a less strongly acidic sulfated mucosubstance with weaker dyeing property within cartilage zone, and smaller chondrocytes size by Alcian blue stain.

• The Korea Journal of Herbology
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• v.28 no.3
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• pp.95-106
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• 2013

Objectives : The researcher investigated the anti-obesity effect of Alismatis Orientale Rhizoma(AP) water extract in mice fed a high fat diet and focused on the analysis of local area adipose tissue. Methods : Male ICR mice were divided into three groups, which were fed either a normal AIN diet, a 45% high fat diet (CT group), or a high fat diet and orally administration with a concentrations of 100 mg/kg (AP100 group) and 300 mg/kg body weight (AP300 group) for eight weeks. Results : As compared with CT group, AP100 group showed significant reductions in absolute weight of liver. As compared with CT group, AP100 group and AP300 group showed significant reductions in weight gain and relative weight of total fat. AST, triglyceride, total-cholesterol levels from the AP 100 group and 300 group were significantly lower than those of the CT, and ALT, LDL-cholesterol levels from the AP 100 group was significantly lower than those of the CT. But serum HDL-cholesterol levels from the AP 100 group and 300 group were significantly higher than those of the CT. And serum adiponectin levels from the AP 100 group was significantly higher than those of the CT. In result of real time PCR, all mRNA expression(PEPCK, G6Pase, PGC-$1{\alpha}$ and $ERR{\gamma}$) of two experimental groups were significantly decreased compared to those of CT group. The treatment with AP on local abdominal area made a fat cell size lessen on the fat tissue in the abdominal cavity and subcutaneous area. Conclusions : These results suggest that AP has an anti-obesity effect and the effect is mediated by inhibition of fat gain.

• Korean Journal of Veterinary Research
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• v.26 no.2
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• pp.283-292
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• 1986

Isolation and identification of Mycoplasma were performed to clarify Mycoplasma infection of mice fed by conventional feeding at two ($K_1$, $K_2$) institutes in Korea. The twenty mice to be tested were randomly sampled from each of 10 breeding colonies in respective institute. Identification of the Mycoplasma strains isolated from the nasal cavity, lung and synovia of mice was made according to the morphology of colonies, biological and biochemical properties with special reference to M. pulmonis, M. arthrotodis and M. neurolyticum. In addition, growth inhibition test was performed using hyperimmune rabbit antisera to the strain PG-22 of M. pulmonis, the strain PG-6 of M, arthritidis and the strain PG-28 of M. neurolyticum and also differentiation of isolates from L-form bacteria was dont by Dieses staining and culture method with passage of the isolates on liquid media eliminated antibacterial drug. On the other hand, a total of 13 strains out of the 44 isolated M. pulmonis from mice was investigated for their susceptibility against 16 antibiotics in vitro. The antibiotic sensitivity test was made using $3{\times}10^4$ organisms/0.3ml on each plate(90mm diameter) with antibiotic mono-or tri-disk. The results obtained are summarized as follows: 1. Out of 20 mice from 10 breeding colonies in Kl institute, mycoplasma-like strains from the nasal cavity of 16 mice(80%) and from the lung of 8 mice(40%) were isolated, while out of 20 mice in K2 institute, M-like strains were isolated from the nasal cavity of 14 mice(70%) and from the lung of 6 mice(30%). However, no mycoplasma-like organisms were isolated from the synovia of the 40 mice examined. All the 44 strains isolated were identified as the organisms of M. pulmonis. 2. Out of the 16 antibiotics tested, penicillin, oleandomycin and bacitracin showed no activity against all the 13 M. pulmonis strains. On the contrary, lincomycin, clindamycin, chloramphenicol, tetracycline, minocycline, kanamycin, gentamycin and tobramycin showed high activity with three different antibiotic concentration of tridisk, but amikasin and spiramycin showed intermediate activity. Other antibiotics such as polymyxin B and colistin showed low activity, while erythromycin showed lower activity than others.