• The Korean Journal of Quaternary Research
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• v.33 no.1_2
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• pp.37-48
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• 2021

The cold surge is an important extreme weather in East Asia during winter, and is largely affected by behavior of the Siberian high Arctic Oscillation, which represents undulation of large-scale pressure pattern in the Arctic region. Recent studies also revealed that the synoptic low pressure system developing in the eastern boundary of the Asian continent is sensitive to sea surface temperature (SST) and plays an important role in strengthening the cold advection over the Korean Peninsula during cold surges. In this study, we analyzed the Arctic Oscillation affecting the large-scale background of cold surge in East Asia, and the sea surface temperature in the coast of East Asia is examined focusing on its role on synoptic low-inducing cold advection. For the analysis, the days with the bottom 3% of the average daily temperature, measured at five surface stations in Korean Peninsula during 49 years (1969/70-2017/18), were used for the cold surge cases. During the negative phase of the Arctic Oscillation, a strong trough is observed over East Asia, and the inflow of cold air from the polar region is strengthened, which lead to frequent cold surges. In addition, anomalously high SST in the eastern coast of Asia increases sensible and latent heat release from the ocean, therefore, it enlarges the likelihood of synoptic low-inducing extreme cold surges.

• Journal of Aquaculture
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• v.21 no.4
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• pp.331-338
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• 2008

Monthly changes in the gonadosomatic index (GSI) and hepatosomatic index (HSI) of wild river puffer Takifugu obscurus, and water quality environment in spawning area during breeding season were investigated from March 1995 to February 1996. Monthly changes in GSI and HSI of T. obscurus, that was cultured in low salinity, were calculated. The external morphology of the gonads, germ cell differentiation during gametogenesis and the reproductive cycle with the gonad developmental phases were investigated by histological analysis. The optimum water quality environment in Ganggyung, Choongcheongnam-do, where is spawning ground of wild T. obscurus, was $15-20^{\circ}C$ (water temperature) and 0 psu (salinity). Monthly changes in the GSI in females and males reached a maximum in May, and then rapidly decreased. Therefore, it is assumed that in the natural condition the spawning period of wild T. obscurus is May to June. In females and males, it showed a negative correlationship between the GSI and HSI. The external morphology of the gonads in female and male T. obscurus, that was cultured in low salinity, is composed of a pair of saccular structure. Based on monthly changes in the GSI, it is assumed that in female T. obscurus, that was cultured in low salinity, spawn from March through May. Therefore, it showed a negative correlationship between changes in the GSI and HSI. On the whole, in females and males, it showed a similar pattern between wild and cultured T. obscurus. The reproductive cycle with the gonad developmental phases can be classified into successive five stages in females: the early growing stage, late growing stage, mature stage, ripe and spent stage, and recovery and resting stage. In males, that can be divided into successive four stages: the growing stage, mature stage, ripe and spent stage, and recovery and resting stage. In case of wild T. obscurus, the spawning period has once a year, however, those cultured in the high water temperature ($20-27^{\circ}C$) - low salinity (under 3.3 psu) condition have reproductive characteristics having possibilities of discharge of eggs and sperms year-round as a multiple spawner.

• Pediatric Infection and Vaccine
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• v.14 no.1
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• pp.97-103
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• 2007

Purpose : Lewis antigen has been known to have a role in the attachment of H. pylori to the gastric mucosa, but its expression pattern in children with H. pylori infection is still unclear. The recently described blood group antigen-binding adhesin BabA is known to mediate adherence of H. pylori to Lewis B receptors on gastric epithelium. We investigated the expression of Lewis antigen in gastric mucosa of Korean children with H. pylori infection. Methods : The expression of Lewis A ($Le^a$), B ($Le^b$), X ($Le^x$), and Y ($Le^y$) was evaluated by immunohistochemistry in H. pylori positive biopsy specimens from 35 children (antral gastritis in 30, peptic ulcer in 5) and in H. pylori negative specimens from 19 children. PCR assays for cagA and babA2 gene of H. pylori were performed. Results : We confirmed the expression of $Le^a$ in 60%, $Le^b$ in 97%, $Le^x$ in 100%, and $Le^y$ in 100% of the superficial epithelium of the 35 H. pylori positive children. In H. pylori negative patients, $Le^a$, $Le^b$, $Le^x$, and $Le^y$ expression was 52%, 100%, 89%, and 100%, respectively. The cagA gene was detected in 65% and babA2 gene in 25% of 35 patients. No differences in neutrophil activity and chronic inflammation were found according to the presence of cagA and babA2 genes in H. pylori. Conclusion : $Le^b$, $Le^x$ and $Le^y$ antigen were highly expressed in gastric mucosa of Korean children, but they were not associated with the status of H. pylori infection and the positivity of babA2 gene. Further studies for other mucosal receptors and toxins are needed to define the immune responses to H. pylori infection in gastric mucosa of Korean children.

• Survey Research
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• v.6 no.2
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• pp.33-50
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• 2005

The purpose of this study was to investigate whether Korean children's being addiction to computer game had an effect on physical health(headache, insomnia, indigestion, cardivascular). We considered both direct effects of that addiction and indirect effects which caused an negative emotion(anxiety). For this study, we collected data from 800 students of grades and 6 in Daejeon, Korea. Among them, we analyzed the data of 572 students[408 boys(71.3%) and 164 girls(28.7%) respectively] who had played computer games for a long period of time(two years or more). Reliability of the scale used on this study was a proper level by $.64{\sim}.91$ and we operated an analysis of structural equation pattern to make relationships of variable causes clear. As a result of examining an index of fitness of each model, it was proved for the fitness of every model(all GFI >.931, all CFI >.939, all NNFI >.929, all RMSEA <.046) to be acceptable. Not only the computer game addiction affected(all ps<.001) directly on physical symptoms(headache ${\beta}$=.211, insomnia ${\beta}$=.289, indigestion ${\beta}$ =.214, cardivascular ${\beta}$=.349), but also it affected(${\beta}$=.458, p<.001) on anxiety. In addition, the effect of anxiety on physical symptoms(headache ${\beta}$=.419, insomnia ${\beta}$=.375, indigestion ${\beta}$=.498, cardivascular ${\beta}$=.328) was significant. As a result of yielding the indirect effects of computer game abuse mediated by anxiety, headache was measured up ${\beta}$=.192, insomnia ${\beta}$=.172, indigestion ${\beta}$ =.228 and cardivascular ${\beta}$=.151. The computer game addiction caused 21% of anxiety and this mediate model proved that the computer game addiction caused 30% of headache, 32% of insomnia, 39% of indigestion, and 34% of cardivascular symptom. As a result of this study, the computer game addiction has a negative effect on physical health both directly and indirectly. Especially, cardivascular was influenced most extremely, then insomnia, indigestion, and headache in order. The implications gleaned from this study were discussed with considerations for future study and practical aspect.

• Korean Journal of Poultry Science
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• v.18 no.3
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• pp.183-196
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• 1991

In order to establish ELISA method to detect antibody against IBV various factors involved were examined. Antigen was prepared from Massachusetts type IBV which is known to be one of serotypes distributed most widely. The virus was grown in embryonated SPF chicken eggs. Allantoic fluid harvested was processed to ultracentrifugation and sucrose density gradient centrifugation to produce a purified antigen The antisera selected from the field samples based on hemagglutination inhibition test were used as the standard positive and negative sera for this study and the results obtained were summarized as follows. 1 , It was found that ELISA test was satisfactory when the purified antigen was coated on the plate in the amount of about 40ng protein per well. In case of the phospholipase treated hemagglutinating antigen it gave satisfactory results when the each well wns coated with 1.2 to 2.5 hemagglutinating unit which was equivalent to 40 to 90ng of protein. 2. There was no significant difference in the ratio of optical density of positive to that of negative serum whether the coated antigen was held for 1 hour at 37$^{\circ}C$ or it was held overnight at 4$^{\circ}C$. The coated antigen could be kept in dried state without change of antigenecity for at least one month of experimental period at 4$^{\circ}C$. 3. There was a big variation in the optical density and P/N values depending on the maker of the plates and on the plate of the same maker. 4. It was found that background optical density was negligible when serum was diluted more than 1：50 and serum dilution of 1：100 appeared to be appropriate as a routine test dilution to screen the antibody. 5. Optical density was fairly constant 15 minutes afterward from the time substrate was treated and during the 4 hours after stopper was treated. 6. There was a low correlation(r＝0.42) between ELISA and HI test. However, when 74serum samples were tested for the IBV antibody, 98.7% were found to be positive by both tests in which titers of 2$^{6}$ or more by HI test and P/N values of 1.4 or more by ELISA were considered to be positive, 7 Day-old IBV vaccinated chickens shows a similar antibody decay and rising pattern until 8 weeks of age by the two tests, ELISA and HI.

• The Korean Journal of Malacology
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• v.21 no.2 s.34
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• pp.121-132
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• 2005

We investigated the reproductive cycle with gonad developmental phases of Sinonovacula constricta by histological observations, and seasonal changes in biochemical component of the adductor muscle, visceral mass, foot muscle and mantle were studied by biochemical analysis, from January to December, 2004. The reproductive cycle of this species can be classifed into five successive stages: early active stage (March to May), late active stage (May to July), ripe stage (July to September), partially spawned stage (August to October) and spentfinactive stage (October to March). Total protein content was the highest in the following order: adductor muscle, visceral mass, foot muscle, and mantle. Except for mantle, it was generally higher during the ripe and spawning stages, while lower during the spent/inactive stage. There were positive correlations in total protein contents among adductor muscle, foot muscle, and visceral mass. However, the correlations were not statistically significant. Total lipid content was the highest in the visceral mass; it was more than 5 or 6-fold higher than those in the adductor muscle, foot muscle, or mantle. The monthly change was also most dynamic in the visceral mass. It first Increased during the early active stage (March to May), decreased during late active stage (May to July), and then increased again rapidly during the spawning stage (September). There were a strong negative correlation in total lipid contents between foot muscle and adductor muscle (r = -0.634, p = 0.027), and a strong positive correlation between adductor muscle and mantle (r = 0.665, p = 0.018). Glycogen contents showed more or less similar pattern to total lipid contents in the adductor muscle, foot muscle, and visceral mass. It was higher during the early active and spawning stages, while lower during the late active and spent/inactive stages. There was no statistically significant correlation in glycogen contents among different tissues. Especially, total lipid content showed a negative correlationship between the foot muscle, adductor muscle, visceral mass and mantle. Therefore, these results indicate that the nutrient content of the foot muscle, adductor muscle, viseral mass and mantle changed in response to gonadal energy needs.

• Korean journal of applied entomology
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• v.24 no.1 s.62
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• pp.29-33
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• 1985

Every plant in $990m^2$ onion field was inspected for damages by the onion maggot. Maps were constructed every ten days to show which plants were infested and which were not from April 11 to May 21, 1984. The maps were sectioned into squares one of which contains 80 onion plants and the counts of damaged onions in each square were fitted to poisson and negative binomial distribution and tested by chi-square. We argue that the satisfactory fitness of the expected negative binomial $[P(x^2)>0.05]$ provided a useful description of the spatial distribution patterns of the damaged onions. Edge effect was tested by the differences of damage ratio and variance/mean ratio (${\sigma}^2/m$) between edge and center part. The result showed that the damage ratioes and variances of all the periods, ${\sigma}^2/m$ values after May 1 were greater in edge part than in center part. Again, the maps were sectioned into four blocks and the squares (sample units) were sectioned into quadrants. By application of the variance component technique, it was suggested that $2{\sim}8$ sample units for 5% sampling error and $1{\sim}2$ sample units for 10% error should be sampled randomly to estimate the damage ratio when $2{\sim}3$ quadrants were inspected.

• The korean journal of orthodontics
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• v.28 no.3 s.68
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• pp.461-477
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• 1998

To evaluate the relapse pattern and long-term stabilities depanding on surgical methods following orthognathic surgery of Cl III patients, the author selected 24 subjects(10 male, 14 female) operated by SSRO and 26 subjects(10 male,16 female) operated by IVRO. Each subject took four lateral cephalograms : just before surgery(T1), within 48hrs after surgery(T2), 4-8 wks after surgery(T3), 6 month or more after surgery(T4), and the landmarks were digitized. The differences of relapse patterns in each interval between two groups were compared and the significance of correlation among the variables of each group was tested. The obtained results are as follows ; 1. Horizontal early relapse was forward movement of mandible in SSRO group, as compared to the backward movement in IVRO group, and there was a statistical significance between the two groups. 2. Vertical early and late relapses were decreases in anterior facial height in both groups and there was no statistical significance between the two groups. 3. There was a statistical significance in negative correlation between mandibular horizontal late relapse and surgical change of articular angle in SSRO group. 4. There was a statistical significance in negative correlation between amount of mandibular set-back and mandibular horizontal early relapse in both groups.

• Korean Journal of Psychosomatic Medicine
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• v.15 no.2
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• pp.81-87
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• 2007

Objectives : The distressed personality (type-D) pattern, consisting of negative affectivity and social inhibition, has been shown by Denollet et al. For measuring the Type D characteristics, Denollet has devised the 14 item Type D scale (DS14). In the present study, this instrument was translated into Korean. The reliability and validity of the Korean DS14 was pilot tested. Methods : Preliminary version of the total 17-item DS14 scale was translated into Korean. 372 controls that did not have any coronary heart diseases (CHD) were randomly sampled in Seoul and Gyeonggi province. Preliminary Korean version was applied to controls and 14 items were finally selected to maximize reliability of the scale. We compared the distribution of type-D personality among the normal controls, hypertensive patients, and the CHD patients. Results : 7 of 10 items in social inhibition were selected and final 14-item version was made. The internal consistency of negative affectivity (0.817) and social inhibition (0.797) were high. In addition, the prevalence of type-D personality in the CHD patients group was significantly higher than normal controls. Conclusion : These findings suggest that Korean version of DS14 is a valid tool for measuring the type D characteristics. Type-D characteristics can be suggested to predict adverse prognosis in patients with CHD.

• Radiation Oncology Journal
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• v.15 no.4
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• pp.321-329
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• 1997

Purpose : It is well known that the risk of lymph nodes metastases to head and neck cancers are influenced by the location and size of the Primary tumor. as well as the degree and types of histological differentiation. However, data on the statistical analyses of lymph node metastases from the head and neck cancers among Korean Population are not available at present. In order to obtain current status of such data, we have analyzed cancer patients at the department of radiation oncology, korea universityhospital for radiation treatment. Materials and Methods : We have evaluated nine-hundred and ninetyseven (997) head and neck cancer Patients who visited to the Department of radiation oncology, between November 1981 to December 1995. After careful physical examinations and CAT scan, Patients were divided into two groups, those with positive lymph node metastases and with negative lymph node metastases. The nodal status were classified according to the TNM system of American Joint Committee on Cancer (AJCC) Besults : Four-hundred and sixteen Patients out of the 997 patients were lymph node positive $(42\%)$ and 581 patients were lymph node negative $(58\%)$ when they were first presented at the department of radiation oncelogy. According to the AJCC classification, the distribution of positive lymph node is as follow: Nl:106 $(25.5\%),\;N2a:100\;(24\%),\;N2b:68\;(16.4\%),\;N2c:69\;(16.6\%),\;3:73\;(15\%).$ respectively. The frequency of lymph node metastases according to the primary sites is as follow : larynx 283 $(28.5\%)$, paranasal sinuses: 182 $(18\%),\;oropharynx:144\;(14.5\%)\;nasopharynx:122(12\%),\;oral\;cavity\;92\;(9\%),\;hypopharynx:71\;(7\%),\;falivary\;gland:58\;(6\%)$ unknown primary:31 $(3\%),\;skin:\;14(2\%)$,. The most frequent Primary site for the positive Iymph node metastases was nasopharynx $(71\%)$ followed by hypopharynx $(69\%),\;oropharynx\;(64\%),\;oral\;cavity\;(39\%)$ The most common histologic type was squamous cell carcinoma (652/997: $65.4\%$). followed by malignant lymphoma $(109/997:11\%)$. Conclusion : Statistical results of lymph node metastases from head and neck cancer at our department were very similar to those obtained from other countries. It is concluded that the location of Primary cancer influences sites of metastases on head and neck, and stage of the primary cancer also influences the development of metastatic lesions. Since the present study is limited on the data collected from one institute. further statistical analyses on Korean cancer Patients are warrented.